openwrt/staging/blogic.git
4 years agoMerge branch 'pipe-rework' (patches from David Howells)
Linus Torvalds [Fri, 6 Dec 2019 00:35:53 +0000 (16:35 -0800)]
Merge branch 'pipe-rework' (patches from David Howells)

Merge two fixes for the pipe rework from David Howells:
 "Here are a couple of patches to fix bugs syzbot found in the pipe
  changes:

   - An assertion check will sometimes trip when polling a pipe because
     the ring size and indices used are approximate and may be being
     changed simultaneously.

     An equivalent approximate calculation was done previously, but
     without the assertion check, so I've just dropped the check. To
     make it accurate, the pipe mutex would need to be taken or the spin
     lock could be used - but usage of the spinlock would need to be
     rolled out into splice, iov_iter and other places for that.

   - The index mask and the max_usage values cannot be cached across
     pipe_wait() as F_SETPIPE_SZ could have been called during the wait.
     This can cause pipe_write() to break"

* pipe-rework:
  pipe: Fix missing mask update after pipe_wait()
  pipe: Remove assertion from pipe_poll()

4 years agopipe: Fix missing mask update after pipe_wait()
David Howells [Thu, 5 Dec 2019 22:30:37 +0000 (22:30 +0000)]
pipe: Fix missing mask update after pipe_wait()

Fix pipe_write() to not cache the ring index mask and max_usage as their
values are invalidated by calling pipe_wait() because the latter
function drops the pipe lock, thereby allowing F_SETPIPE_SZ change them.
Without this, pipe_write() may subsequently miscalculate the array
indices and pipe fullness, leading to an oops like the following:

  BUG: KASAN: slab-out-of-bounds in pipe_write+0xc25/0xe10 fs/pipe.c:481
  Write of size 8 at addr ffff8880771167a8 by task syz-executor.3/7987
  ...
  CPU: 1 PID: 7987 Comm: syz-executor.3 Not tainted 5.4.0-rc2-syzkaller #0
  ...
  Call Trace:
    pipe_write+0xc25/0xe10 fs/pipe.c:481
    call_write_iter include/linux/fs.h:1895 [inline]
    new_sync_write+0x3fd/0x7e0 fs/read_write.c:483
    __vfs_write+0x94/0x110 fs/read_write.c:496
    vfs_write+0x18a/0x520 fs/read_write.c:558
    ksys_write+0x105/0x220 fs/read_write.c:611
    __do_sys_write fs/read_write.c:623 [inline]
    __se_sys_write fs/read_write.c:620 [inline]
    __x64_sys_write+0x6e/0xb0 fs/read_write.c:620
    do_syscall_64+0xca/0x5d0 arch/x86/entry/common.c:290
    entry_SYSCALL_64_after_hwframe+0x49/0xbe

This is not a problem for pipe_read() as the mask is recalculated on
each pass of the loop, after pipe_wait() has been called.

Fixes: 8cefc107ca54 ("pipe: Use head and tail pointers for the ring, not cursor and length")
Reported-by: syzbot+838eb0878ffd51f27c41@syzkaller.appspotmail.com
Signed-off-by: David Howells <dhowells@redhat.com>
Cc: Eric Biggers <ebiggers@kernel.org>
[ Changed it to use a temporary variable 'mask' to avoid long lines -Linus ]
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agopipe: Remove assertion from pipe_poll()
David Howells [Thu, 5 Dec 2019 22:30:30 +0000 (22:30 +0000)]
pipe: Remove assertion from pipe_poll()

An assertion check was added to pipe_poll() to make sure that the ring
occupancy isn't seen to overflow the ring size.  However, since no locks
are held when the three values are read, it is possible for F_SETPIPE_SZ
to intervene and muck up the calculation, thereby causing the oops.

Fix this by simply removing the assertion and accepting that the
calculation might be approximate.

Note that the previous code also had a similar issue, though there was
no assertion check, since the occupancy counter and the ring size were
not read with a lock held, so it's possible that the poll check might
have malfunctioned then too.

Also wake up all the waiters so that they can reissue their checks if
there was a competing read or write.

Fixes: 8cefc107ca54 ("pipe: Use head and tail pointers for the ring, not cursor and length")
Reported-by: syzbot+d37abaade33a934f16f2@syzkaller.appspotmail.com
Signed-off-by: David Howells <dhowells@redhat.com>
cc: Eric Biggers <ebiggers@kernel.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agoMerge tag 'gfs2-for-5.5' of git://git.kernel.org/pub/scm/linux/kernel/git/gfs2/linux...
Linus Torvalds [Thu, 5 Dec 2019 21:20:11 +0000 (13:20 -0800)]
Merge tag 'gfs2-for-5.5' of git://git./linux/kernel/git/gfs2/linux-gfs2

Pull GFS2 updates from Andreas Gruenbacher:
 "Bob's extensive filesystem withdrawal and recovery testing:
   - don't write log headers after file system withdraw
   - clean up iopen glock mess in gfs2_create_inode
   - close timing window with GLF_INVALIDATE_IN_PROGRESS
   - abort gfs2_freeze if io error is seen
   - don't loop forever in gfs2_freeze if withdrawn
   - fix infinite loop in gfs2_ail1_flush on io error
   - introduce function gfs2_withdrawn
   - fix glock reference problem in gfs2_trans_remove_revoke

  Filesystems with a block size smaller than the page size:
   - fix end-of-file handling in gfs2_page_mkwrite
   - improve mmap write vs. punch_hole consistency

  Other:
   - remove active journal side effect from gfs2_write_log_header
   - multi-block allocations in gfs2_page_mkwrite

  Minor cleanups and coding style fixes:
   - remove duplicate call from gfs2_create_inode
   - make gfs2_log_shutdown static
   - make gfs2_fs_parameters static
   - some whitespace cleanups
   - removed unnecessary semicolon"

* tag 'gfs2-for-5.5' of git://git.kernel.org/pub/scm/linux/kernel/git/gfs2/linux-gfs2:
  gfs2: Don't write log headers after file system withdraw
  gfs2: Remove duplicate call from gfs2_create_inode
  gfs2: clean up iopen glock mess in gfs2_create_inode
  gfs2: Close timing window with GLF_INVALIDATE_IN_PROGRESS
  gfs2: Abort gfs2_freeze if io error is seen
  gfs2: Don't loop forever in gfs2_freeze if withdrawn
  gfs2: fix infinite loop in gfs2_ail1_flush on io error
  gfs2: Introduce function gfs2_withdrawn
  gfs2: fix glock reference problem in gfs2_trans_remove_revoke
  gfs2: make gfs2_log_shutdown static
  gfs2: Remove active journal side effect from gfs2_write_log_header
  gfs2: Fix end-of-file handling in gfs2_page_mkwrite
  gfs2: Multi-block allocations in gfs2_page_mkwrite
  gfs2: Improve mmap write vs. punch_hole consistency
  gfs2: make gfs2_fs_parameters static
  gfs2: Some whitespace cleanups
  gfs2: removed unnecessary semicolon

4 years agoMerge tag 'ceph-for-5.5-rc1' of git://github.com/ceph/ceph-client
Linus Torvalds [Thu, 5 Dec 2019 21:06:51 +0000 (13:06 -0800)]
Merge tag 'ceph-for-5.5-rc1' of git://github.com/ceph/ceph-client

Pull ceph updates from Ilya Dryomov:
 "The two highlights are a set of improvements to how rbd read-only
  mappings are handled and a conversion to the new mount API (slightly
  complicated by the fact that we had a common option parsing framework
  that called out into rbd and the filesystem instead of them calling
  into it).

  Also included a few scattered fixes and a MAINTAINERS update for rbd,
  adding Dongsheng as a reviewer"

* tag 'ceph-for-5.5-rc1' of git://github.com/ceph/ceph-client:
  libceph, rbd, ceph: convert to use the new mount API
  rbd: ask for a weaker incompat mask for read-only mappings
  rbd: don't query snapshot features
  rbd: remove snapshot existence validation code
  rbd: don't establish watch for read-only mappings
  rbd: don't acquire exclusive lock for read-only mappings
  rbd: disallow read-write partitions on images mapped read-only
  rbd: treat images mapped read-only seriously
  rbd: introduce RBD_DEV_FLAG_READONLY
  rbd: introduce rbd_is_snap()
  ceph: don't leave ino field in ceph_mds_request_head uninitialized
  ceph: tone down loglevel on ceph_mdsc_build_path warning
  rbd: update MAINTAINERS info
  ceph: fix geting random mds from mdsmap
  rbd: fix spelling mistake "requeueing" -> "requeuing"
  ceph: make several helper accessors take const pointers
  libceph: drop unnecessary check from dispatch() in mon_client.c

4 years agoMerge tag 'fuse-update-5.5' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi...
Linus Torvalds [Thu, 5 Dec 2019 20:44:22 +0000 (12:44 -0800)]
Merge tag 'fuse-update-5.5' of git://git./linux/kernel/git/mszeredi/fuse

Pull fuse update from Miklos Szeredi:

 - Fix a regression introduced in the last release

 - Fix a number of issues with validating data coming from userspace

 - Some cleanups in virtiofs

* tag 'fuse-update-5.5' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse:
  fuse: fix Kconfig indentation
  fuse: fix leak of fuse_io_priv
  virtiofs: Use completions while waiting for queue to be drained
  virtiofs: Do not send forget request "struct list_head" element
  virtiofs: Use a common function to send forget
  virtiofs: Fix old-style declaration
  fuse: verify nlink
  fuse: verify write return
  fuse: verify attributes

4 years agoMerge tag 'modules-for-v5.5' of git://git.kernel.org/pub/scm/linux/kernel/git/jeyu...
Linus Torvalds [Thu, 5 Dec 2019 20:27:16 +0000 (12:27 -0800)]
Merge tag 'modules-for-v5.5' of git://git./linux/kernel/git/jeyu/linux

Pull modules updates from Jessica Yu:
 "Summary of modules changes for the 5.5 merge window:

   - Refactor include/linux/export.h and remove code duplication between
     EXPORT_SYMBOL and EXPORT_SYMBOL_NS to make it more readable.

     The most notable change is that no namespace is represented by an
     empty string "" rather than NULL.

   - Fix a module load/unload race where waiter(s) trying to load the
     same module weren't being woken up when a module finally goes away"

* tag 'modules-for-v5.5' of git://git.kernel.org/pub/scm/linux/kernel/git/jeyu/linux:
  kernel/module.c: wakeup processes in module_wq on module unload
  moduleparam: fix parameter description mismatch
  export: avoid code duplication in include/linux/export.h

4 years agoMerge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/gerg/m68knommu
Linus Torvalds [Thu, 5 Dec 2019 20:20:42 +0000 (12:20 -0800)]
Merge branch 'for-next' of git://git./linux/kernel/git/gerg/m68knommu

Pull m68knommu update from Greg Ungerer:
 "Only a single change, to enable coldfire preemption entry code for all
  preemption types"

* 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/gerg/m68knommu:
  m68k/coldfire: Use CONFIG_PREEMPTION

4 years agoMerge tag 'armsoc-defconfig' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc
Linus Torvalds [Thu, 5 Dec 2019 20:14:19 +0000 (12:14 -0800)]
Merge tag 'armsoc-defconfig' of git://git./linux/kernel/git/soc/soc

Pull ARM SoC defconfig updates from Olof Johansson:
 "We keep this in a separate branch to avoid cross-branch conflicts, but
  most of the material here is fairly boring -- some new drivers turned
  on for hardware since they were merged, and some refreshed files due
  to time having moved a lot of entries around"

* tag 'armsoc-defconfig' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc: (36 commits)
  ARM: config: multi_v5: ASPEED SDHCI, SGPIO
  ARM: configs: multi_v7: ASPEED network, gpio, FSI
  ARM: config: aspeed-g4: Add MMC, and cleanup
  ARM: config: aspeed-g5: Add SGPIO and FSI drivers
  ARM: config: aspeed-g5: Enable 8250_DW quirks
  arm64: defconfig: Change CONFIG_AT803X_PHY from m to y
  ARM: shmobile: defconfig: Refresh for v5.4-rc1
  arm64: defconfig: Enable R8A77961 SoC
  ARM: configs: sunxi: Enable MICREL_PHY
  arm64: defconfig: add new Allwinner crypto options
  ARM: configs: sunxi: add new Allwinner crypto options
  ARM: tegra: Enable Tegra VDE driver in tegra_defconfig
  ARM: imx_v6_v7_defconfig: Enable CONFIG_TOUCHSCREEN_DA9052
  arm64: defconfig: Enable configs for S32V234
  arm64: defconfig: Enable CONFIG_KEYBOARD_IMX_SC_KEY as module
  arm64: defconfig: Enable SMMU v3 PMCG
  arm64: defconfig: Enable HiSilicon ZIP controller
  arm64: defconfig: enable Altera GPIO controller
  ARM: multi_v7_defconfig: Enable audio support for stm32mp157
  arm64: defconfig: enable rsu driver
  ...

4 years agoMerge tag 'armsoc-dt' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc
Linus Torvalds [Thu, 5 Dec 2019 20:09:47 +0000 (12:09 -0800)]
Merge tag 'armsoc-dt' of git://git./linux/kernel/git/soc/soc

Pull ARM Device-tree updates from Olof Johansson:
 "As always, the bulk of updates.  Some of the news this cycle:

  New SoC descriptions:
   - Broadcom BCM2711
   - Amlogic Meson A1 and G12
   - Freescale S32V234
   - Marvell Armada AP807/AP807-quad and CP115
   - Realtek RTD1293 and RTD1296
   - Rockchip RK3308

  New boards and platforms:
   - Allwinner: NanoPi Duo2
   - Amlogic: Ugoos am6
   - Atmel at91: Overkiz Kizbox2/4
   - Broadcom: RPi4, Luxul XWC-2000
   - Marvell: New Espressobin flavor
   - NXP: i.MX8MN LPDDR4 EVK, i.MX8QXP Colibri, S32V234 EVB, Netronix
     E60K02 and Kobo Clara HD, Kontron N6311 and N6411, OPOS6UL and
     OPOS6ULDev
   - Renesas: Salvator-XS
   - Rockchip: Beelink A1 (rk3308), rk3308 eval boards, rk3399-roc-pc"

* tag 'armsoc-dt' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc: (653 commits)
  ARM: dts: logicpd-torpedo: Disable USB Host
  arm: dts: mt6323: add keys, power-controller, rtc and codec
  arm64: dts: mt8183: add systimer0 device node
  dt-bindings: mediatek: update bindings for MT8183 systimer
  arm64: dts: rockchip: fix sdmmc detection on boot on rk3328-roc-cc
  arm64: dts: rockchip: Split rk3399-roc-pc for with and without mezzanine board.
  arm64: dts: rockchip: Add Beelink A1
  dt-bindings: ARM: rockchip: Add Beelink A1
  arm64: dts: rockchip: Add RK3328 audio pipelines
  arm64: dts: ti: k3-j721e-common-proc-board: Add USB ports
  arm64: dts: ti: k3-j721e-main: add USB controller nodes
  ARM: dts: aspeed-g6: Add timer description
  ARM: dts: aspeed: ast2600evb: Enable i2c buses
  ARM: dts: at91: add a dts and dtsi file for kizbox2 based boards
  dt-bindings: arm: at91: Document Kizbox2-2 board binding
  arm64: dts: meson-gx: fix i2c compatible
  arm64: dts: meson-gx: cec node should be disabled by default
  arm64: dts: meson-g12b-odroid-n2: add missing amlogic, s922x compatible
  arm64: dts: meson-gxm: fix gpu irq order
  arm64: dts: meson-g12a: fix gpu irq order
  ...

4 years agoMerge tag 'armsoc-drivers' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc
Linus Torvalds [Thu, 5 Dec 2019 19:43:31 +0000 (11:43 -0800)]
Merge tag 'armsoc-drivers' of git://git./linux/kernel/git/soc/soc

Pull ARM SoC driver updates from Olof Johansson:
 "Various driver updates for platforms:

   - A larger set of work on Tegra 2/3 around memory controller and
     regulator features, some fuse cleanups, etc..

   - MMP platform drivers, in particular for USB PHY, and other smaller
     additions.

   - Samsung Exynos 5422 driver for DMC (dynamic memory configuration),
     and ASV (adaptive voltage), allowing the platform to run at more
     optimal operating points.

   - Misc refactorings and support for RZ/G2N and R8A774B1 from Renesas

   - Clock/reset control driver for TI/OMAP

   - Meson-A1 reset controller support

   - Qualcomm sdm845 and sda845 SoC IDs for socinfo"

* tag 'armsoc-drivers' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc: (150 commits)
  firmware: arm_scmi: Fix doorbell ring logic for !CONFIG_64BIT
  soc: fsl: add RCPM driver
  dt-bindings: fsl: rcpm: Add 'little-endian' and update Chassis definition
  memory: tegra: Consolidate registers definition into common header
  memory: tegra: Ensure timing control debug features are disabled
  memory: tegra: Introduce Tegra30 EMC driver
  memory: tegra: Do not handle error from wait_for_completion_timeout()
  memory: tegra: Increase handshake timeout on Tegra20
  memory: tegra: Print a brief info message about EMC timings
  memory: tegra: Pre-configure debug register on Tegra20
  memory: tegra: Include io.h instead of iopoll.h
  memory: tegra: Adapt for Tegra20 clock driver changes
  memory: tegra: Don't set EMC rate to maximum on probe for Tegra20
  memory: tegra: Add gr2d and gr3d to DRM IOMMU group
  memory: tegra: Set DMA mask based on supported address bits
  soc: at91: Add Atmel SFR SN (Serial Number) support
  memory: atmel-ebi: switch to SPDX license identifiers
  memory: atmel-ebi: move NUM_CS definition inside EBI driver
  soc: mediatek: Refactor bus protection control
  soc: mediatek: Refactor sram control
  ...

4 years agoMerge tag 'armsoc-soc' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc
Linus Torvalds [Thu, 5 Dec 2019 19:38:40 +0000 (11:38 -0800)]
Merge tag 'armsoc-soc' of git://git./linux/kernel/git/soc/soc

Pull ARM SoC platform updates from Olof Johansson:
 "Most of these are for MMP (seeing a bunch of cleanups and refactorings
  for the first time in a while), and for OMAP (a bunch of cleanups and
  added support for voltage controller on OMAP4430)"

* tag 'armsoc-soc' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc: (51 commits)
  ARM: OMAP2+: Add missing put_device() call in omapdss_init_of()
  OMAP2: fixup doc comments in omap_device
  ARM: OMAP1: drop duplicated dependency on ARCH_OMAP1
  ARM: ASPEED: update default ARCH_NR_GPIO for ARCH_ASPEED
  ARM: imx: use generic function to exit coherency
  ARM: tegra: Use WFE for power-gating on Tegra30
  ARM: tegra: Fix FLOW_CTLR_HALT register clobbering by tegra_resume()
  ARM: exynos: Enable exynos-asv driver for ARCH_EXYNOS
  ARM: s3c: Rename s5p_usb_phy functions
  ARM: s3c: Rename s3c64xx_spi_setname() function
  ARM: imx: Add serial number support for i.MX6/7 SoCs
  ARM: imx: Drop imx_anatop_usb_chrg_detect_disable()
  arm64: Introduce config for S32
  ARM: hisi: drop useless depend on ARCH_MULTI_V7
  arm64: realtek: Select reset controller
  ARM: shmobile: rcar-gen2: Drop legacy DT clock support
  ARM: OMAP2+: Remove duplicated include from pmic-cpcap.c
  ARM: OMAP1: ams-delta FIQ: Fix a typo ("Initiaize")
  MAINTAINERS: Add logicpd-som-lv and logicpd-torpedo to OMAP TREE
  ARM: OMAP2+: pdata-quirks: drop TI_ST/KIM support
  ...

4 years agoMerge tag 'pwm/for-5.5-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/thierry...
Linus Torvalds [Thu, 5 Dec 2019 19:28:14 +0000 (11:28 -0800)]
Merge tag 'pwm/for-5.5-rc1' of git://git./linux/kernel/git/thierry.reding/linux-pwm

Pull pwm updates from Thierry Reding:
 "Various changes and minor fixes across a couple of drivers"

* tag 'pwm/for-5.5-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/thierry.reding/linux-pwm:
  pwm: stm32: Pass breakinput instead of its values
  pwm: stm32: Remove clutter from ternary operator
  pwm: stm32: Validate breakinput data from DT
  pwm: Update comment on struct pwm_ops::apply
  pwm: sun4i: Fix incorrect calculation of duty_cycle/period
  pwm: stm32: Add power management support
  pwm: stm32: Split breakinput apply routine to ease PM support
  dt-bindings: pwm-stm32: Document pinctrl sleep state
  pwm: sun4i: Drop redundant assignment to variable pval
  dt-bindings: pwm: mediatek: Remove gratuitous compatible string for MT7629

4 years agoMerge branch 'thermal/next' of git://git.kernel.org/pub/scm/linux/kernel/git/thermal...
Linus Torvalds [Thu, 5 Dec 2019 19:21:24 +0000 (11:21 -0800)]
Merge branch 'thermal/next' of git://git./linux/kernel/git/thermal/linux

Pull thermal management updates from Zhang Rui:

 - Fix a deadlock regression in thermal core framework, which was
   introduced in 5.3 (Wei Wang)

 - Initialize thermal control framework earlier to enable thermal
   mitigation during boot (Amit Kucheria)

 - Convert the Intelligent Power Allocator (IPA) thermal governor to
   follow the generic PM_EM instead of its own Energy Model (Quentin
   Perret)

 - Introduce a new Amlogic soc thermal driver (Guillaume La Roque)

 - Add interrupt support for tsens thermal driver (Amit Kucheria)

 - Add support for MSM8956/8976 in tsens thermal driver
   (AngeloGioacchino Del Regno)

 - Add support for r8a774b1 in rcar thermal driver (Biju Das)

 - Add support for Thermal Monitor Unit v2 in qoriq thermal driver
   (Yuantian Tang)

 - Some other fixes/cleanups on thermal core framework and soc thermal
   drivers (Colin Ian King, Daniel Lezcano, Hsin-Yi Wang, Tian Tao)

* 'thermal/next' of git://git.kernel.org/pub/scm/linux/kernel/git/thermal/linux: (32 commits)
  thermal: Fix deadlock in thermal thermal_zone_device_check
  thermal: cpu_cooling: Migrate to using the EM framework
  thermal: cpu_cooling: Make the power-related code depend on IPA
  PM / EM: Declare EM data types unconditionally
  arm64: defconfig: Enable CONFIG_ENERGY_MODEL
  drivers: thermal: tsens: fix potential integer overflow on multiply
  thermal: cpu_cooling: Reorder the header file
  thermal: cpu_cooling: Remove pointless dependency on CONFIG_OF
  thermal: no need to set .owner when using module_platform_driver
  thermal: qcom: tsens-v1: Fix kfree of a non-pointer value
  cpufreq: qcom-hw: Move driver initialization earlier
  clk: qcom: Initialize clock drivers earlier
  cpufreq: Initialize cpufreq-dt driver earlier
  cpufreq: Initialize the governors in core_initcall
  thermal: Initialize thermal subsystem earlier
  thermal: Remove netlink support
  dt: thermal: tsens: Document compatible for MSM8976/56
  thermal: qcom: tsens-v1: Add support for MSM8956 and MSM8976
  MAINTAINERS: add entry for Amlogic Thermal driver
  thermal: amlogic: Add thermal driver to support G12 SoCs
  ...

4 years agoMerge branch 'akpm' (patches from Andrew)
Linus Torvalds [Thu, 5 Dec 2019 17:46:26 +0000 (09:46 -0800)]
Merge branch 'akpm' (patches from Andrew)

Merge more updates from Andrew Morton:
 "Most of the rest of MM and various other things. Some Kconfig rework
  still awaits merges of dependent trees from linux-next.

  Subsystems affected by this patch series: mm/hotfixes, mm/memcg,
  mm/vmstat, mm/thp, procfs, sysctl, misc, notifiers, core-kernel,
  bitops, lib, checkpatch, epoll, binfmt, init, rapidio, uaccess, kcov,
  ubsan, ipc, bitmap, mm/pagemap"

* akpm: (86 commits)
  mm: remove __ARCH_HAS_4LEVEL_HACK and include/asm-generic/4level-fixup.h
  um: add support for folded p4d page tables
  um: remove unused pxx_offset_proc() and addr_pte() functions
  sparc32: use pgtable-nopud instead of 4level-fixup
  parisc/hugetlb: use pgtable-nopXd instead of 4level-fixup
  parisc: use pgtable-nopXd instead of 4level-fixup
  nds32: use pgtable-nopmd instead of 4level-fixup
  microblaze: use pgtable-nopmd instead of 4level-fixup
  m68k: mm: use pgtable-nopXd instead of 4level-fixup
  m68k: nommu: use pgtable-nopud instead of 4level-fixup
  c6x: use pgtable-nopud instead of 4level-fixup
  arm: nommu: use pgtable-nopud instead of 4level-fixup
  alpha: use pgtable-nopud instead of 4level-fixup
  gpio: pca953x: tighten up indentation
  gpio: pca953x: convert to use bitmap API
  gpio: pca953x: use input from regs structure in pca953x_irq_pending()
  gpio: pca953x: remove redundant variable and check in IRQ handler
  lib/bitmap: introduce bitmap_replace() helper
  lib/test_bitmap: fix comment about this file
  lib/test_bitmap: move exp1 and exp2 upper for others to use
  ...

4 years agomm: remove __ARCH_HAS_4LEVEL_HACK and include/asm-generic/4level-fixup.h
Mike Rapoport [Thu, 5 Dec 2019 00:54:32 +0000 (16:54 -0800)]
mm: remove __ARCH_HAS_4LEVEL_HACK and include/asm-generic/4level-fixup.h

There are no architectures that use include/asm-generic/4level-fixup.h
therefore it can be removed along with __ARCH_HAS_4LEVEL_HACK define.

Link: http://lkml.kernel.org/r/1572938135-31886-14-git-send-email-rppt@kernel.org
Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Cc: Anatoly Pugachev <matorola@gmail.com>
Cc: Anton Ivanov <anton.ivanov@cambridgegreys.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Greentime Hu <green.hu@gmail.com>
Cc: Greg Ungerer <gerg@linux-m68k.org>
Cc: Helge Deller <deller@gmx.de>
Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: "Kirill A. Shutemov" <kirill@shutemov.name>
Cc: Mark Salter <msalter@redhat.com>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Peter Rosin <peda@axentia.se>
Cc: Richard Weinberger <richard@nod.at>
Cc: Rolf Eike Beer <eike-kernel@sf-tec.de>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Russell King <rmk+kernel@armlinux.org.uk>
Cc: Sam Creasey <sammy@sammy.net>
Cc: Vincent Chen <deanbo422@gmail.com>
Cc: Vineet Gupta <Vineet.Gupta1@synopsys.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agoum: add support for folded p4d page tables
Mike Rapoport [Thu, 5 Dec 2019 00:54:28 +0000 (16:54 -0800)]
um: add support for folded p4d page tables

The UML port uses 4 and 5 level fixups to support higher level page
table directories in the generic VM code.

Implement primitives necessary for the 4th level folding, add walks of
p4d level where appropriate and drop usage of __ARCH_USE_5LEVEL_HACK.

Link: http://lkml.kernel.org/r/1572938135-31886-13-git-send-email-rppt@kernel.org
Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Cc: Anatoly Pugachev <matorola@gmail.com>
Cc: Anton Ivanov <anton.ivanov@cambridgegreys.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Greentime Hu <green.hu@gmail.com>
Cc: Greg Ungerer <gerg@linux-m68k.org>
Cc: Helge Deller <deller@gmx.de>
Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: "Kirill A. Shutemov" <kirill@shutemov.name>
Cc: Mark Salter <msalter@redhat.com>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Peter Rosin <peda@axentia.se>
Cc: Richard Weinberger <richard@nod.at>
Cc: Rolf Eike Beer <eike-kernel@sf-tec.de>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Russell King <rmk+kernel@armlinux.org.uk>
Cc: Sam Creasey <sammy@sammy.net>
Cc: Vincent Chen <deanbo422@gmail.com>
Cc: Vineet Gupta <Vineet.Gupta1@synopsys.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agoum: remove unused pxx_offset_proc() and addr_pte() functions
Mike Rapoport [Thu, 5 Dec 2019 00:54:24 +0000 (16:54 -0800)]
um: remove unused pxx_offset_proc() and addr_pte() functions

The pxx_offset_proc() and addr_pte() functions are never used.  Remove
them.

Link: http://lkml.kernel.org/r/1572938135-31886-12-git-send-email-rppt@kernel.org
Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Acked-by: Richard Weinberger <richard@nod.at>
Cc: Anatoly Pugachev <matorola@gmail.com>
Cc: Anton Ivanov <anton.ivanov@cambridgegreys.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Greentime Hu <green.hu@gmail.com>
Cc: Greg Ungerer <gerg@linux-m68k.org>
Cc: Helge Deller <deller@gmx.de>
Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: "Kirill A. Shutemov" <kirill@shutemov.name>
Cc: Mark Salter <msalter@redhat.com>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Peter Rosin <peda@axentia.se>
Cc: Rolf Eike Beer <eike-kernel@sf-tec.de>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Russell King <rmk+kernel@armlinux.org.uk>
Cc: Sam Creasey <sammy@sammy.net>
Cc: Vincent Chen <deanbo422@gmail.com>
Cc: Vineet Gupta <Vineet.Gupta1@synopsys.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agosparc32: use pgtable-nopud instead of 4level-fixup
Mike Rapoport [Thu, 5 Dec 2019 00:54:20 +0000 (16:54 -0800)]
sparc32: use pgtable-nopud instead of 4level-fixup

32-bit version of sparc has three-level page tables and can use
pgtable-nopud and folding of the upper layers.

Replace usage of include/asm-generic/4level-fixup.h with
include/asm-generic/pgtable-nopud.h and adjust page table manipulation
macros and functions accordingly.

Link: http://lkml.kernel.org/r/1572938135-31886-11-git-send-email-rppt@kernel.org
Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Acked-by: David S. Miller <davem@davemloft.net>
Tested-by: Anatoly Pugachev <matorola@gmail.com>
Cc: Anton Ivanov <anton.ivanov@cambridgegreys.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Greentime Hu <green.hu@gmail.com>
Cc: Greg Ungerer <gerg@linux-m68k.org>
Cc: Helge Deller <deller@gmx.de>
Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: "Kirill A. Shutemov" <kirill@shutemov.name>
Cc: Mark Salter <msalter@redhat.com>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Peter Rosin <peda@axentia.se>
Cc: Richard Weinberger <richard@nod.at>
Cc: Rolf Eike Beer <eike-kernel@sf-tec.de>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Russell King <rmk+kernel@armlinux.org.uk>
Cc: Sam Creasey <sammy@sammy.net>
Cc: Vincent Chen <deanbo422@gmail.com>
Cc: Vineet Gupta <Vineet.Gupta1@synopsys.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agoparisc/hugetlb: use pgtable-nopXd instead of 4level-fixup
Helge Deller [Thu, 5 Dec 2019 00:54:16 +0000 (16:54 -0800)]
parisc/hugetlb: use pgtable-nopXd instead of 4level-fixup

Link: http://lkml.kernel.org/r/1572938135-31886-10-git-send-email-rppt@kernel.org
Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Cc: Anatoly Pugachev <matorola@gmail.com>
Cc: Anton Ivanov <anton.ivanov@cambridgegreys.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Greentime Hu <green.hu@gmail.com>
Cc: Greg Ungerer <gerg@linux-m68k.org>
Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: "Kirill A. Shutemov" <kirill@shutemov.name>
Cc: Mark Salter <msalter@redhat.com>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Peter Rosin <peda@axentia.se>
Cc: Richard Weinberger <richard@nod.at>
Cc: Rolf Eike Beer <eike-kernel@sf-tec.de>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Russell King <rmk+kernel@armlinux.org.uk>
Cc: Sam Creasey <sammy@sammy.net>
Cc: Vincent Chen <deanbo422@gmail.com>
Cc: Vineet Gupta <Vineet.Gupta1@synopsys.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agoparisc: use pgtable-nopXd instead of 4level-fixup
Mike Rapoport [Thu, 5 Dec 2019 00:54:12 +0000 (16:54 -0800)]
parisc: use pgtable-nopXd instead of 4level-fixup

parisc has two or three levels of page tables and can use appropriate
pgtable-nopXd and folding of the upper layers.

Replace usage of include/asm-generic/4level-fixup.h and explicit
definitions of __PAGETABLE_PxD_FOLDED in parisc with
include/asm-generic/pgtable-nopmd.h for two-level configurations and
with include/asm-generic/pgtable-nopud.h for three-lelve configurations
and adjust page table manipulation macros and functions accordingly.

Link: http://lkml.kernel.org/r/1572938135-31886-9-git-send-email-rppt@kernel.org
Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Acked-by: Helge Deller <deller@gmx.de>
Cc: Anatoly Pugachev <matorola@gmail.com>
Cc: Anton Ivanov <anton.ivanov@cambridgegreys.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Greentime Hu <green.hu@gmail.com>
Cc: Greg Ungerer <gerg@linux-m68k.org>
Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: "Kirill A. Shutemov" <kirill@shutemov.name>
Cc: Mark Salter <msalter@redhat.com>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Peter Rosin <peda@axentia.se>
Cc: Richard Weinberger <richard@nod.at>
Cc: Rolf Eike Beer <eike-kernel@sf-tec.de>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Russell King <rmk+kernel@armlinux.org.uk>
Cc: Sam Creasey <sammy@sammy.net>
Cc: Vincent Chen <deanbo422@gmail.com>
Cc: Vineet Gupta <Vineet.Gupta1@synopsys.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agonds32: use pgtable-nopmd instead of 4level-fixup
Mike Rapoport [Thu, 5 Dec 2019 00:54:08 +0000 (16:54 -0800)]
nds32: use pgtable-nopmd instead of 4level-fixup

nds32 has only two-level page tables and can use pgtable-nopmd and
folding of the upper layers.

Replace usage of include/asm-generic/4level-fixup.h and explicit
definition of __PAGETABLE_PMD_FOLDED in nds32 with
include/asm-generic/pgtable-nopmd.h and adjust page table manipulation
macros and functions accordingly.

Link: http://lkml.kernel.org/r/1572938135-31886-8-git-send-email-rppt@kernel.org
Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Cc: Anatoly Pugachev <matorola@gmail.com>
Cc: Anton Ivanov <anton.ivanov@cambridgegreys.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Greentime Hu <green.hu@gmail.com>
Cc: Greg Ungerer <gerg@linux-m68k.org>
Cc: Helge Deller <deller@gmx.de>
Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: "Kirill A. Shutemov" <kirill@shutemov.name>
Cc: Mark Salter <msalter@redhat.com>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Peter Rosin <peda@axentia.se>
Cc: Richard Weinberger <richard@nod.at>
Cc: Rolf Eike Beer <eike-kernel@sf-tec.de>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Russell King <rmk+kernel@armlinux.org.uk>
Cc: Sam Creasey <sammy@sammy.net>
Cc: Vincent Chen <deanbo422@gmail.com>
Cc: Vineet Gupta <Vineet.Gupta1@synopsys.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agomicroblaze: use pgtable-nopmd instead of 4level-fixup
Mike Rapoport [Thu, 5 Dec 2019 00:54:03 +0000 (16:54 -0800)]
microblaze: use pgtable-nopmd instead of 4level-fixup

microblaze has only two-level page tables and can use pgtable-nopmd and
folding of the upper layers.

Replace usage of include/asm-generic/4level-fixup.h and explicit
definition of __PAGETABLE_PMD_FOLDED in microblaze with
include/asm-generic/pgtable-nopmd.h and adjust page table manipulation
macros and functions accordingly.

Link: http://lkml.kernel.org/r/1572938135-31886-7-git-send-email-rppt@kernel.org
Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Cc: Anatoly Pugachev <matorola@gmail.com>
Cc: Anton Ivanov <anton.ivanov@cambridgegreys.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Greentime Hu <green.hu@gmail.com>
Cc: Greg Ungerer <gerg@linux-m68k.org>
Cc: Helge Deller <deller@gmx.de>
Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: "Kirill A. Shutemov" <kirill@shutemov.name>
Cc: Mark Salter <msalter@redhat.com>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Peter Rosin <peda@axentia.se>
Cc: Richard Weinberger <richard@nod.at>
Cc: Rolf Eike Beer <eike-kernel@sf-tec.de>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Russell King <rmk+kernel@armlinux.org.uk>
Cc: Sam Creasey <sammy@sammy.net>
Cc: Vincent Chen <deanbo422@gmail.com>
Cc: Vineet Gupta <Vineet.Gupta1@synopsys.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agom68k: mm: use pgtable-nopXd instead of 4level-fixup
Mike Rapoport [Thu, 5 Dec 2019 00:53:59 +0000 (16:53 -0800)]
m68k: mm: use pgtable-nopXd instead of 4level-fixup

m68k has two or three levels of page tables and can use appropriate
pgtable-nopXd and folding of the upper layers.

Replace usage of include/asm-generic/4level-fixup.h and explicit
definitions of __PAGETABLE_PxD_FOLDED in m68k with
include/asm-generic/pgtable-nopmd.h for two-level configurations and
with include/asm-generic/pgtable-nopud.h for three-lelve configurations
and adjust page table manipulation macros and functions accordingly.

[akpm@linux-foundation.org: fix merge glitch]
[geert@linux-m68k.org: more merge glitch fixes]
[akpm@linux-foundation.org: s/bad_pgd/bad_pud/, per Mike]
Link: http://lkml.kernel.org/r/1572938135-31886-6-git-send-email-rppt@kernel.org
Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Acked-by: Greg Ungerer <gerg@linux-m68k.org>
Cc: Anatoly Pugachev <matorola@gmail.com>
Cc: Anton Ivanov <anton.ivanov@cambridgegreys.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Greentime Hu <green.hu@gmail.com>
Cc: Helge Deller <deller@gmx.de>
Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: "Kirill A. Shutemov" <kirill@shutemov.name>
Cc: Mark Salter <msalter@redhat.com>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Peter Rosin <peda@axentia.se>
Cc: Richard Weinberger <richard@nod.at>
Cc: Rolf Eike Beer <eike-kernel@sf-tec.de>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Russell King <rmk+kernel@armlinux.org.uk>
Cc: Sam Creasey <sammy@sammy.net>
Cc: Vincent Chen <deanbo422@gmail.com>
Cc: Vineet Gupta <Vineet.Gupta1@synopsys.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agom68k: nommu: use pgtable-nopud instead of 4level-fixup
Mike Rapoport [Thu, 5 Dec 2019 00:53:55 +0000 (16:53 -0800)]
m68k: nommu: use pgtable-nopud instead of 4level-fixup

The generic nommu implementation of page table manipulation takes care
of folding of the upper levels and does not require fixups.

Simply replace of include/asm-generic/4level-fixup.h with
include/asm-generic/pgtable-nopud.h.

Link: http://lkml.kernel.org/r/1572938135-31886-5-git-send-email-rppt@kernel.org
Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Acked-by: Greg Ungerer <gerg@linux-m68k.org>
Cc: Anatoly Pugachev <matorola@gmail.com>
Cc: Anton Ivanov <anton.ivanov@cambridgegreys.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Greentime Hu <green.hu@gmail.com>
Cc: Helge Deller <deller@gmx.de>
Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: "Kirill A. Shutemov" <kirill@shutemov.name>
Cc: Mark Salter <msalter@redhat.com>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Peter Rosin <peda@axentia.se>
Cc: Richard Weinberger <richard@nod.at>
Cc: Rolf Eike Beer <eike-kernel@sf-tec.de>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Russell King <rmk+kernel@armlinux.org.uk>
Cc: Sam Creasey <sammy@sammy.net>
Cc: Vincent Chen <deanbo422@gmail.com>
Cc: Vineet Gupta <Vineet.Gupta1@synopsys.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agoc6x: use pgtable-nopud instead of 4level-fixup
Mike Rapoport [Thu, 5 Dec 2019 00:53:52 +0000 (16:53 -0800)]
c6x: use pgtable-nopud instead of 4level-fixup

c6x is a nommu architecture and does not require fixup for upper layers
of the page tables because it is already handled by the generic nommu
implementation.

Replace usage of include/asm-generic/4level-fixup.h with
include/asm-generic/pgtable-nopud.h

Link: http://lkml.kernel.org/r/1572938135-31886-4-git-send-email-rppt@kernel.org
Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Cc: Anatoly Pugachev <matorola@gmail.com>
Cc: Anton Ivanov <anton.ivanov@cambridgegreys.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Greentime Hu <green.hu@gmail.com>
Cc: Greg Ungerer <gerg@linux-m68k.org>
Cc: Helge Deller <deller@gmx.de>
Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: "Kirill A. Shutemov" <kirill@shutemov.name>
Cc: Mark Salter <msalter@redhat.com>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Peter Rosin <peda@axentia.se>
Cc: Richard Weinberger <richard@nod.at>
Cc: Rolf Eike Beer <eike-kernel@sf-tec.de>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Russell King <rmk+kernel@armlinux.org.uk>
Cc: Sam Creasey <sammy@sammy.net>
Cc: Vincent Chen <deanbo422@gmail.com>
Cc: Vineet Gupta <Vineet.Gupta1@synopsys.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agoarm: nommu: use pgtable-nopud instead of 4level-fixup
Mike Rapoport [Thu, 5 Dec 2019 00:53:48 +0000 (16:53 -0800)]
arm: nommu: use pgtable-nopud instead of 4level-fixup

The generic nommu implementation of page table manipulation takes care
of folding of the upper levels and does not require fixups.

Simply replace of include/asm-generic/4level-fixup.h with
include/asm-generic/pgtable-nopud.h.

Link: http://lkml.kernel.org/r/1572938135-31886-3-git-send-email-rppt@kernel.org
Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Acked-by: Russell King <rmk+kernel@armlinux.org.uk>
Cc: Anatoly Pugachev <matorola@gmail.com>
Cc: Anton Ivanov <anton.ivanov@cambridgegreys.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Greentime Hu <green.hu@gmail.com>
Cc: Greg Ungerer <gerg@linux-m68k.org>
Cc: Helge Deller <deller@gmx.de>
Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: "Kirill A. Shutemov" <kirill@shutemov.name>
Cc: Mark Salter <msalter@redhat.com>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Peter Rosin <peda@axentia.se>
Cc: Richard Weinberger <richard@nod.at>
Cc: Rolf Eike Beer <eike-kernel@sf-tec.de>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Sam Creasey <sammy@sammy.net>
Cc: Vincent Chen <deanbo422@gmail.com>
Cc: Vineet Gupta <Vineet.Gupta1@synopsys.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agoalpha: use pgtable-nopud instead of 4level-fixup
Mike Rapoport [Thu, 5 Dec 2019 00:53:44 +0000 (16:53 -0800)]
alpha: use pgtable-nopud instead of 4level-fixup

Patch series "mm: remove __ARCH_HAS_4LEVEL_HACK", v13.

These patches convert several architectures to use page table folding
and remove __ARCH_HAS_4LEVEL_HACK along with
include/asm-generic/4level-fixup.h.

For the nommu configurations the folding is already implemented by the
generic code so the only change was to use the appropriate header file.

As for the rest, the changes are mostly about mechanical replacement of
pgd accessors with pud/pmd ones and the addition of higher levels to
page table traversals.

With Vineet's patches from "elide extraneous generated code for folded
p4d/pud/pmd" series [1] there is a small shrink of the kernel size of
about -0.01% for the defconfig builds.

This patch (of 13):

It is not likely alpha will have 5-level page tables.

Replace usage of include/asm-generic/4level-fixup.h and implied
__ARCH_HAS_4LEVEL_HACK with include/asm-generic/pgtable-nopud.h and
adjust page table manipulation macros and functions accordingly.

Link: http://lkml.kernel.org/r/1572938135-31886-2-git-send-email-rppt@kernel.org
Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Cc: Anton Ivanov <anton.ivanov@cambridgegreys.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Greentime Hu <green.hu@gmail.com>
Cc: Greg Ungerer <gerg@linux-m68k.org>
Cc: Helge Deller <deller@gmx.de>
Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: "Kirill A. Shutemov" <kirill@shutemov.name>
Cc: Mark Salter <msalter@redhat.com>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Peter Rosin <peda@axentia.se>
Cc: Richard Weinberger <richard@nod.at>
Cc: Rolf Eike Beer <eike-kernel@sf-tec.de>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Sam Creasey <sammy@sammy.net>
Cc: Vincent Chen <deanbo422@gmail.com>
Cc: Vineet Gupta <Vineet.Gupta1@synopsys.com>
Cc: Anatoly Pugachev <matorola@gmail.com>
Cc: Russell King <rmk+kernel@armlinux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agogpio: pca953x: tighten up indentation
Andy Shevchenko [Thu, 5 Dec 2019 00:53:40 +0000 (16:53 -0800)]
gpio: pca953x: tighten up indentation

There is no need to split some of the lines.  However, improve the style
of multi-line comment.  On top of this there is no need to have double
space.

Correct above indentation issues without altering the functionality.

Link: http://lkml.kernel.org/r/20191022172922.61232-12-andriy.shevchenko@linux.intel.com
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Cc: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Marek Vasut <marek.vasut+renesas@gmail.com>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Thomas Petazzoni <thomas.petazzoni@bootlin.com>
Cc: William Breathitt Gray <vilhelm.gray@gmail.com>
Cc: Yury Norov <yury.norov@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agogpio: pca953x: convert to use bitmap API
Andy Shevchenko [Thu, 5 Dec 2019 00:53:37 +0000 (16:53 -0800)]
gpio: pca953x: convert to use bitmap API

Instead of customized approach convert the driver to use bitmap API.

[andriy.shevchenko@linux.intel.com: reduce stack usage in couple of functions]
Link: http://lkml.kernel.org/r/20191023153056.64262-1-andriy.shevchenko@linux.intel.com
Link: http://lkml.kernel.org/r/20191022172922.61232-11-andriy.shevchenko@linux.intel.com
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Cc: William Breathitt Gray <vilhelm.gray@gmail.com>
Cc: Thomas Petazzoni <thomas.petazzoni@bootlin.com>
Cc: Marek Vasut <marek.vasut+renesas@gmail.com>
Cc: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Yury Norov <yury.norov@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agogpio: pca953x: use input from regs structure in pca953x_irq_pending()
Andy Shevchenko [Thu, 5 Dec 2019 00:53:33 +0000 (16:53 -0800)]
gpio: pca953x: use input from regs structure in pca953x_irq_pending()

While PCA_PCAL is defined for PCA953X type only, we still may use an
offset of the input from regs structure for sake of consistency.

Link: http://lkml.kernel.org/r/20191022172922.61232-10-andriy.shevchenko@linux.intel.com
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Cc: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Marek Vasut <marek.vasut+renesas@gmail.com>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Thomas Petazzoni <thomas.petazzoni@bootlin.com>
Cc: William Breathitt Gray <vilhelm.gray@gmail.com>
Cc: Yury Norov <yury.norov@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agogpio: pca953x: remove redundant variable and check in IRQ handler
Andy Shevchenko [Thu, 5 Dec 2019 00:53:30 +0000 (16:53 -0800)]
gpio: pca953x: remove redundant variable and check in IRQ handler

We always will have at least one iteration of the loop due to pending
being guaranteed to be non-zero.  That is, we may remove extra variable
and check in the IRQ handler.

Link: http://lkml.kernel.org/r/20191022172922.61232-9-andriy.shevchenko@linux.intel.com
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Cc: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Marek Vasut <marek.vasut+renesas@gmail.com>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Thomas Petazzoni <thomas.petazzoni@bootlin.com>
Cc: William Breathitt Gray <vilhelm.gray@gmail.com>
Cc: Yury Norov <yury.norov@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agolib/bitmap: introduce bitmap_replace() helper
Andy Shevchenko [Thu, 5 Dec 2019 00:53:26 +0000 (16:53 -0800)]
lib/bitmap: introduce bitmap_replace() helper

In some drivers we want to have a single operation over bitmap which is
an equivalent to:

*dst = (*old & ~(*mask)) | (*new & *mask)

Introduce bitmap_replace() helper for this.

Link: http://lkml.kernel.org/r/20191022172922.61232-8-andriy.shevchenko@linux.intel.com
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Marek Vasut <marek.vasut+renesas@gmail.com>
Cc: Thomas Petazzoni <thomas.petazzoni@bootlin.com>
Cc: William Breathitt Gray <vilhelm.gray@gmail.com>
Cc: Yury Norov <yury.norov@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agolib/test_bitmap: fix comment about this file
Andy Shevchenko [Thu, 5 Dec 2019 00:53:23 +0000 (16:53 -0800)]
lib/test_bitmap: fix comment about this file

This test case file is about bitmap API, and not printf() facility.

Link: http://lkml.kernel.org/r/20191022172922.61232-7-andriy.shevchenko@linux.intel.com
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Cc: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Marek Vasut <marek.vasut+renesas@gmail.com>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Thomas Petazzoni <thomas.petazzoni@bootlin.com>
Cc: William Breathitt Gray <vilhelm.gray@gmail.com>
Cc: Yury Norov <yury.norov@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agolib/test_bitmap: move exp1 and exp2 upper for others to use
Andy Shevchenko [Thu, 5 Dec 2019 00:53:20 +0000 (16:53 -0800)]
lib/test_bitmap: move exp1 and exp2 upper for others to use

Some test cases may re-use predefined exp1 and exp2 bitmaps.  Move them
upper in the file.

Link: http://lkml.kernel.org/r/20191022172922.61232-6-andriy.shevchenko@linux.intel.com
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Cc: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Marek Vasut <marek.vasut+renesas@gmail.com>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Thomas Petazzoni <thomas.petazzoni@bootlin.com>
Cc: William Breathitt Gray <vilhelm.gray@gmail.com>
Cc: Yury Norov <yury.norov@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agolib/test_bitmap: rename exp to exp1 to avoid ambiguous name
Andy Shevchenko [Thu, 5 Dec 2019 00:53:17 +0000 (16:53 -0800)]
lib/test_bitmap: rename exp to exp1 to avoid ambiguous name

One function is using exp as local variable.  Avoid ambiguous naming by
rename global one to exp1.

Link: http://lkml.kernel.org/r/20191022172922.61232-5-andriy.shevchenko@linux.intel.com
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Cc: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Marek Vasut <marek.vasut+renesas@gmail.com>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Thomas Petazzoni <thomas.petazzoni@bootlin.com>
Cc: William Breathitt Gray <vilhelm.gray@gmail.com>
Cc: Yury Norov <yury.norov@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agolib/test_bitmap: name EXP_BYTES properly
Andy Shevchenko [Thu, 5 Dec 2019 00:53:13 +0000 (16:53 -0800)]
lib/test_bitmap: name EXP_BYTES properly

EXP_BYTES has been wrongly named.  It's a size of the exp array in bits.

While here, go ahead and rename to EXP1_IN_BITS to avoid double renaming
when exp will be renamed to exp1 in the next patch

Link: http://lkml.kernel.org/r/20191022172922.61232-4-andriy.shevchenko@linux.intel.com
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Cc: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Marek Vasut <marek.vasut+renesas@gmail.com>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Thomas Petazzoni <thomas.petazzoni@bootlin.com>
Cc: William Breathitt Gray <vilhelm.gray@gmail.com>
Cc: Yury Norov <yury.norov@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agolib/test_bitmap: undefine macros after use
Andy Shevchenko [Thu, 5 Dec 2019 00:53:09 +0000 (16:53 -0800)]
lib/test_bitmap: undefine macros after use

There is no need to keep step and ptest macros defined in entire file.

Link: http://lkml.kernel.org/r/20191022172922.61232-3-andriy.shevchenko@linux.intel.com
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Cc: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Marek Vasut <marek.vasut+renesas@gmail.com>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Thomas Petazzoni <thomas.petazzoni@bootlin.com>
Cc: William Breathitt Gray <vilhelm.gray@gmail.com>
Cc: Yury Norov <yury.norov@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agolib/test_bitmap: force argument of bitmap_parselist_user() to proper address space
Andy Shevchenko [Thu, 5 Dec 2019 00:53:06 +0000 (16:53 -0800)]
lib/test_bitmap: force argument of bitmap_parselist_user() to proper address space

Patch series "gpio: pca953x: Convert to bitmap (extended) API", v2.

While converting gpio-pca953x driver to bitmap API, I noticed that we
have no function to replace bits.

So, that's how patch 7 appears.

First 6 patches are preparatory of the test suite (including some
warning fixes, etc).

Patches 8-9 are preparatory for the GPIO driver to be easier converted
to bitmap API, conversion to which happens in patch 10.

Patch 11 contains simple indentation fixes.

This patch (of 11):

Sparse complains:

  lib/test_bitmap.c:345:58: warning: incorrect type in argument 1 (different address spaces)
  lib/test_bitmap.c:345:58:    expected char const [noderef] <asn:1> *ubuf
  lib/test_bitmap.c:345:58:    got char const *const in

Force argument of bitmap_parselist_user() to proper address space.

Link: http://lkml.kernel.org/r/20191022172922.61232-2-andriy.shevchenko@linux.intel.com
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Cc: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Yury Norov <yury.norov@gmail.com>
Cc: William Breathitt Gray <vilhelm.gray@gmail.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Thomas Petazzoni <thomas.petazzoni@bootlin.com>
Cc: Marek Vasut <marek.vasut+renesas@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agoarch: sembuf.h: make uapi asm/sembuf.h self-contained
Masahiro Yamada [Thu, 5 Dec 2019 00:53:03 +0000 (16:53 -0800)]
arch: sembuf.h: make uapi asm/sembuf.h self-contained

Userspace cannot compile <asm/sembuf.h> due to some missing type
definitions.  For example, building it for x86 fails as follows:

    CC      usr/include/asm/sembuf.h.s
  In file included from <command-line>:32:0:
  usr/include/asm/sembuf.h:17:20: error: field `sem_perm' has incomplete type
    struct ipc64_perm sem_perm; /* permissions .. see ipc.h */
                      ^~~~~~~~
  usr/include/asm/sembuf.h:24:2: error: unknown type name `__kernel_time_t'
    __kernel_time_t sem_otime; /* last semop time */
    ^~~~~~~~~~~~~~~
  usr/include/asm/sembuf.h:25:2: error: unknown type name `__kernel_ulong_t'
    __kernel_ulong_t __unused1;
    ^~~~~~~~~~~~~~~~
  usr/include/asm/sembuf.h:26:2: error: unknown type name `__kernel_time_t'
    __kernel_time_t sem_ctime; /* last change time */
    ^~~~~~~~~~~~~~~
  usr/include/asm/sembuf.h:27:2: error: unknown type name `__kernel_ulong_t'
    __kernel_ulong_t __unused2;
    ^~~~~~~~~~~~~~~~
  usr/include/asm/sembuf.h:29:2: error: unknown type name `__kernel_ulong_t'
    __kernel_ulong_t sem_nsems; /* no. of semaphores in array */
    ^~~~~~~~~~~~~~~~
  usr/include/asm/sembuf.h:30:2: error: unknown type name `__kernel_ulong_t'
    __kernel_ulong_t __unused3;
    ^~~~~~~~~~~~~~~~
  usr/include/asm/sembuf.h:31:2: error: unknown type name `__kernel_ulong_t'
    __kernel_ulong_t __unused4;
    ^~~~~~~~~~~~~~~~

It is just a matter of missing include directive.

Include <asm/ipcbuf.h> to make it self-contained, and add it to
the compile-test coverage.

Link: http://lkml.kernel.org/r/20191030063855.9989-3-yamada.masahiro@socionext.com
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agoarch: msgbuf.h: make uapi asm/msgbuf.h self-contained
Masahiro Yamada [Thu, 5 Dec 2019 00:53:00 +0000 (16:53 -0800)]
arch: msgbuf.h: make uapi asm/msgbuf.h self-contained

Userspace cannot compile <asm/msgbuf.h> due to some missing type
definitions.  For example, building it for x86 fails as follows:

    CC      usr/include/asm/msgbuf.h.s
  In file included from usr/include/asm/msgbuf.h:6:0,
                   from <command-line>:32:
  usr/include/asm-generic/msgbuf.h:25:20: error: field `msg_perm' has incomplete type
    struct ipc64_perm msg_perm;
                      ^~~~~~~~
  usr/include/asm-generic/msgbuf.h:27:2: error: unknown type name `__kernel_time_t'
    __kernel_time_t msg_stime; /* last msgsnd time */
    ^~~~~~~~~~~~~~~
  usr/include/asm-generic/msgbuf.h:28:2: error: unknown type name `__kernel_time_t'
    __kernel_time_t msg_rtime; /* last msgrcv time */
    ^~~~~~~~~~~~~~~
  usr/include/asm-generic/msgbuf.h:29:2: error: unknown type name `__kernel_time_t'
    __kernel_time_t msg_ctime; /* last change time */
    ^~~~~~~~~~~~~~~
  usr/include/asm-generic/msgbuf.h:41:2: error: unknown type name `__kernel_pid_t'
    __kernel_pid_t msg_lspid; /* pid of last msgsnd */
    ^~~~~~~~~~~~~~
  usr/include/asm-generic/msgbuf.h:42:2: error: unknown type name `__kernel_pid_t'
    __kernel_pid_t msg_lrpid; /* last receive pid */
    ^~~~~~~~~~~~~~

It is just a matter of missing include directive.

Include <asm/ipcbuf.h> to make it self-contained, and add it to
the compile-test coverage.

Link: http://lkml.kernel.org/r/20191030063855.9989-2-yamada.masahiro@socionext.com
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agoarch: ipcbuf.h: make uapi asm/ipcbuf.h self-contained
Masahiro Yamada [Thu, 5 Dec 2019 00:52:57 +0000 (16:52 -0800)]
arch: ipcbuf.h: make uapi asm/ipcbuf.h self-contained

Userspace cannot compile <asm/ipcbuf.h> due to some missing type
definitions.  For example, building it for x86 fails as follows:

    CC      usr/include/asm/ipcbuf.h.s
  In file included from usr/include/asm/ipcbuf.h:1:0,
                   from <command-line>:32:
  usr/include/asm-generic/ipcbuf.h:21:2: error: unknown type name `__kernel_key_t'
    __kernel_key_t  key;
    ^~~~~~~~~~~~~~
  usr/include/asm-generic/ipcbuf.h:22:2: error: unknown type name `__kernel_uid32_t'
    __kernel_uid32_t uid;
    ^~~~~~~~~~~~~~~~
  usr/include/asm-generic/ipcbuf.h:23:2: error: unknown type name `__kernel_gid32_t'
    __kernel_gid32_t gid;
    ^~~~~~~~~~~~~~~~
  usr/include/asm-generic/ipcbuf.h:24:2: error: unknown type name `__kernel_uid32_t'
    __kernel_uid32_t cuid;
    ^~~~~~~~~~~~~~~~
  usr/include/asm-generic/ipcbuf.h:25:2: error: unknown type name `__kernel_gid32_t'
    __kernel_gid32_t cgid;
    ^~~~~~~~~~~~~~~~
  usr/include/asm-generic/ipcbuf.h:26:2: error: unknown type name `__kernel_mode_t'
    __kernel_mode_t  mode;
    ^~~~~~~~~~~~~~~
  usr/include/asm-generic/ipcbuf.h:28:35: error: `__kernel_mode_t' undeclared here (not in a function)
    unsigned char  __pad1[4 - sizeof(__kernel_mode_t)];
                                     ^~~~~~~~~~~~~~~
  usr/include/asm-generic/ipcbuf.h:31:2: error: unknown type name `__kernel_ulong_t'
    __kernel_ulong_t __unused1;
    ^~~~~~~~~~~~~~~~
  usr/include/asm-generic/ipcbuf.h:32:2: error: unknown type name `__kernel_ulong_t'
    __kernel_ulong_t __unused2;
    ^~~~~~~~~~~~~~~~

It is just a matter of missing include directive.

Include <linux/posix_types.h> to make it self-contained, and add it to
the compile-test coverage.

Link: http://lkml.kernel.org/r/20191030063855.9989-1-yamada.masahiro@socionext.com
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agolib/ubsan: don't serialize UBSAN report
Julien Grall [Thu, 5 Dec 2019 00:52:53 +0000 (16:52 -0800)]
lib/ubsan: don't serialize UBSAN report

At the moment, UBSAN report will be serialized using a spin_lock().  On
RT-systems, spinlocks are turned to rt_spin_lock and may sleep.  This
will result to the following splat if the undefined behavior is in a
context that can sleep:

  BUG: sleeping function called from invalid context at /src/linux/kernel/locking/rtmutex.c:968
  in_atomic(): 1, irqs_disabled(): 128, pid: 3447, name: make
  1 lock held by make/3447:
   #0: 000000009a966332 (&mm->mmap_sem){++++}, at: do_page_fault+0x140/0x4f8
  irq event stamp: 6284
  hardirqs last  enabled at (6283): [<ffff000011326520>] _raw_spin_unlock_irqrestore+0x90/0xa0
  hardirqs last disabled at (6284): [<ffff0000113262b0>] _raw_spin_lock_irqsave+0x30/0x78
  softirqs last  enabled at (2430): [<ffff000010088ef8>] fpsimd_restore_current_state+0x60/0xe8
  softirqs last disabled at (2427): [<ffff000010088ec0>] fpsimd_restore_current_state+0x28/0xe8
  Preemption disabled at:
  [<ffff000011324a4c>] rt_mutex_futex_unlock+0x4c/0xb0
  CPU: 3 PID: 3447 Comm: make Tainted: G        W         5.2.14-rt7-01890-ge6e057589653 #911
  Call trace:
    dump_backtrace+0x0/0x148
    show_stack+0x14/0x20
    dump_stack+0xbc/0x104
    ___might_sleep+0x154/0x210
    rt_spin_lock+0x68/0xa0
    ubsan_prologue+0x30/0x68
    handle_overflow+0x64/0xe0
    __ubsan_handle_add_overflow+0x10/0x18
    __lock_acquire+0x1c28/0x2a28
    lock_acquire+0xf0/0x370
    _raw_spin_lock_irqsave+0x58/0x78
    rt_mutex_futex_unlock+0x4c/0xb0
    rt_spin_unlock+0x28/0x70
    get_page_from_freelist+0x428/0x2b60
    __alloc_pages_nodemask+0x174/0x1708
    alloc_pages_vma+0x1ac/0x238
    __handle_mm_fault+0x4ac/0x10b0
    handle_mm_fault+0x1d8/0x3b0
    do_page_fault+0x1c8/0x4f8
    do_translation_fault+0xb8/0xe0
    do_mem_abort+0x3c/0x98
    el0_da+0x20/0x24

The spin_lock() will protect against multiple CPUs to output a report
together, I guess to prevent them from being interleaved.  However, they
can still interleave with other messages (and even splat from
__might_sleep).

So the lock usefulness seems pretty limited.  Rather than trying to
accomodate RT-system by switching to a raw_spin_lock(), the lock is now
completely dropped.

Link: http://lkml.kernel.org/r/20190920100835.14999-1-julien.grall@arm.com
Signed-off-by: Julien Grall <julien.grall@arm.com>
Reported-by: Andre Przywara <andre.przywara@arm.com>
Acked-by: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agovhost, kcov: collect coverage from vhost_worker
Andrey Konovalov [Thu, 5 Dec 2019 00:52:50 +0000 (16:52 -0800)]
vhost, kcov: collect coverage from vhost_worker

Add kcov_remote_start()/kcov_remote_stop() annotations to the
vhost_worker() function, which is responsible for processing vhost
works.

Since vhost_worker() threads are spawned per vhost device instance the
common kcov handle is used for kcov_remote_start()/stop() annotations
(see Documentation/dev-tools/kcov.rst for details).  As the result kcov
can now be used to collect coverage from vhost worker threads.

Link: http://lkml.kernel.org/r/e49d5d154e5da6c9ada521d2b7ce10a49ce9f98b.1572366574.git.andreyknvl@google.com
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: Alexander Potapenko <glider@google.com>
Cc: Anders Roxell <anders.roxell@linaro.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: David Windsor <dwindsor@gmail.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Elena Reshetova <elena.reshetova@intel.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jason Wang <jasowang@redhat.com>
Cc: Marco Elver <elver@google.com>
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agousb, kcov: collect coverage from hub_event
Andrey Konovalov [Thu, 5 Dec 2019 00:52:47 +0000 (16:52 -0800)]
usb, kcov: collect coverage from hub_event

Add kcov_remote_start()/kcov_remote_stop() annotations to the
hub_event() function, which is responsible for processing events on USB
buses, in particular events that happen during USB device enumeration.

Since hub_event() is run in a global background kernel thread (see
Documentation/dev-tools/kcov.rst for details), each USB bus gets a
unique global handle from the USB subsystem kcov handle range.  As the
result kcov can now be used to collect coverage from events that happen
on a particular USB bus.

[akpm@linux-foundation.org: avoid patch conflicts to make life easier for Andrew]
Link: http://lkml.kernel.org/r/de4fe1c219db2d002d905dc1736e2a3bfa1db997.1572366574.git.andreyknvl@google.com
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: Alexander Potapenko <glider@google.com>
Cc: Anders Roxell <anders.roxell@linaro.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: David Windsor <dwindsor@gmail.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Elena Reshetova <elena.reshetova@intel.com>
Cc: Jason Wang <jasowang@redhat.com>
Cc: Marco Elver <elver@google.com>
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agokcov: remote coverage support
Andrey Konovalov [Thu, 5 Dec 2019 00:52:43 +0000 (16:52 -0800)]
kcov: remote coverage support

Patch series " kcov: collect coverage from usb and vhost", v3.

This patchset extends kcov to allow collecting coverage from backgound
kernel threads.  This extension requires custom annotations for each of
the places where coverage collection is desired.  This patchset
implements this for hub events in the USB subsystem and for vhost
workers.  See the first patch description for details about the kcov
extension.  The other two patches apply this kcov extension to USB and
vhost.

Examples of other subsystems that might potentially benefit from this
when custom annotations are added (the list is based on
process_one_work() callers for bugs recently reported by syzbot):

1. fs: writeback wb_workfn() worker,
2. net: addrconf_dad_work()/addrconf_verify_work() workers,
3. net: neigh_periodic_work() worker,
4. net/p9: p9_write_work()/p9_read_work() workers,
5. block: blk_mq_run_work_fn() worker.

These patches have been used to enable coverage-guided USB fuzzing with
syzkaller for the last few years, see the details here:

  https://github.com/google/syzkaller/blob/master/docs/linux/external_fuzzing_usb.md

This patchset has been pushed to the public Linux kernel Gerrit
instance:

  https://linux-review.googlesource.com/c/linux/kernel/git/torvalds/linux/+/1524

This patch (of 3):

Add background thread coverage collection ability to kcov.

With KCOV_ENABLE coverage is collected only for syscalls that are issued
from the current process.  With KCOV_REMOTE_ENABLE it's possible to
collect coverage for arbitrary parts of the kernel code, provided that
those parts are annotated with kcov_remote_start()/kcov_remote_stop().

This allows to collect coverage from two types of kernel background
threads: the global ones, that are spawned during kernel boot in a
limited number of instances (e.g.  one USB hub_event() worker thread is
spawned per USB HCD); and the local ones, that are spawned when a user
interacts with some kernel interface (e.g.  vhost workers).

To enable collecting coverage from a global background thread, a unique
global handle must be assigned and passed to the corresponding
kcov_remote_start() call.  Then a userspace process can pass a list of
such handles to the KCOV_REMOTE_ENABLE ioctl in the handles array field
of the kcov_remote_arg struct.  This will attach the used kcov device to
the code sections, that are referenced by those handles.

Since there might be many local background threads spawned from
different userspace processes, we can't use a single global handle per
annotation.  Instead, the userspace process passes a non-zero handle
through the common_handle field of the kcov_remote_arg struct.  This
common handle gets saved to the kcov_handle field in the current
task_struct and needs to be passed to the newly spawned threads via
custom annotations.  Those threads should in turn be annotated with
kcov_remote_start()/kcov_remote_stop().

Internally kcov stores handles as u64 integers.  The top byte of a
handle is used to denote the id of a subsystem that this handle belongs
to, and the lower 4 bytes are used to denote the id of a thread instance
within that subsystem.  A reserved value 0 is used as a subsystem id for
common handles as they don't belong to a particular subsystem.  The
bytes 4-7 are currently reserved and must be zero.  In the future the
number of bytes used for the subsystem or handle ids might be increased.

When a particular userspace process collects coverage by via a common
handle, kcov will collect coverage for each code section that is
annotated to use the common handle obtained as kcov_handle from the
current task_struct.  However non common handles allow to collect
coverage selectively from different subsystems.

Link: http://lkml.kernel.org/r/e90e315426a384207edbec1d6aa89e43008e4caf.1572366574.git.andreyknvl@google.com
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Jason Wang <jasowang@redhat.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: David Windsor <dwindsor@gmail.com>
Cc: Elena Reshetova <elena.reshetova@intel.com>
Cc: Anders Roxell <anders.roxell@linaro.org>
Cc: Alexander Potapenko <glider@google.com>
Cc: Marco Elver <elver@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agouaccess: disallow > INT_MAX copy sizes
Kees Cook [Thu, 5 Dec 2019 00:52:40 +0000 (16:52 -0800)]
uaccess: disallow > INT_MAX copy sizes

As we've done with VFS, string operations, etc, reject usercopy sizes
larger than INT_MAX, which would be nice to have for catching bugs
related to size calculation overflows[1].

This adds 10 bytes to x86_64 defconfig text and 1980 bytes to the data
section:

     text    data     bss     dec     hex filename
  19691167        5134320 1646664 26472151        193eed7 vmlinux.before
  19691177        5136300 1646664 26474141        193f69d vmlinux.after

[1] https://marc.info/?l=linux-s390&m=156631939010493&w=2

Link: http://lkml.kernel.org/r/201908251612.F9902D7A@keescook
Signed-off-by: Kees Cook <keescook@chromium.org>
Suggested-by: Dan Carpenter <dan.carpenter@oracle.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agodrm: limit to INT_MAX in create_blob ioctl
Daniel Vetter [Thu, 5 Dec 2019 00:52:37 +0000 (16:52 -0800)]
drm: limit to INT_MAX in create_blob ioctl

The hardened usercpy code is too paranoid ever since commit 6a30afa8c1fb
("uaccess: disallow > INT_MAX copy sizes")

Code itself should have been fine as-is.

Link: http://lkml.kernel.org/r/20191106164755.31478-1-daniel.vetter@ffwll.ch
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Reported-by: syzbot+fb77e97ebf0612ee6914@syzkaller.appspotmail.com
Fixes: 6a30afa8c1fb ("uaccess: disallow > INT_MAX copy sizes")
Cc: Kees Cook <keescook@chromium.org>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agodrivers/rapidio/rio-access.c: fix missing include of <linux/rio_drv.h>
Ben Dooks (Codethink) [Thu, 5 Dec 2019 00:52:34 +0000 (16:52 -0800)]
drivers/rapidio/rio-access.c: fix missing include of <linux/rio_drv.h>

Include <linux/rio_drv.h> for the missing declarations of functions
exported from this file.  Fixes the following sparse warnings:

  drivers/rapidio/rio-access.c:59:1: warning: symbol '__rio_local_read_config_8' was not declared. Should it be static?
  drivers/rapidio/rio-access.c:60:1: warning: symbol '__rio_local_read_config_16' was not declared. Should it be static?
  drivers/rapidio/rio-access.c:61:1: warning: symbol '__rio_local_read_config_32' was not declared. Should it be static?
  drivers/rapidio/rio-access.c:62:1: warning: symbol '__rio_local_write_config_8' was not declared. Should it be static?
  drivers/rapidio/rio-access.c:63:1: warning: symbol '__rio_local_write_config_16' was not declared. Should it be static?
  drivers/rapidio/rio-access.c:64:1: warning: symbol '__rio_local_write_config_32' was not declared. Should it be static?
  drivers/rapidio/rio-access.c:112:1: warning: symbol 'rio_mport_read_config_8' was not declared. Should it be static?
  drivers/rapidio/rio-access.c:113:1: warning: symbol 'rio_mport_read_config_16' was not declared. Should it be static?
  drivers/rapidio/rio-access.c:114:1: warning: symbol 'rio_mport_read_config_32' was not declared. Should it be static?
  drivers/rapidio/rio-access.c:115:1: warning: symbol 'rio_mport_write_config_8' was not declared. Should it be static?
  drivers/rapidio/rio-access.c:116:1: warning: symbol 'rio_mport_write_config_16' was not declared. Should it be static?
  drivers/rapidio/rio-access.c:117:1: warning: symbol 'rio_mport_write_config_32' was not declared. Should it be static?
  drivers/rapidio/rio-access.c:136:5: warning: symbol 'rio_mport_send_doorbell' was not declared. Should it be static?

Link: http://lkml.kernel.org/r/20191017115103.684-1-ben.dooks@codethink.co.uk
Signed-off-by: Ben Dooks <ben.dooks@codethink.co.uk>
Cc: Matt Porter <mporter@kernel.crashing.org>
Cc: Alexandre Bounine <alex.bou9@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agodrivers/rapidio/rio-driver.c: fix missing include of <linux/rio_drv.h>
Ben Dooks (Codethink) [Thu, 5 Dec 2019 00:52:31 +0000 (16:52 -0800)]
drivers/rapidio/rio-driver.c: fix missing include of <linux/rio_drv.h>

Include <linux/rio_drv.h> for the missing declarations of functions
exported from this file.  Fixes the following sparse warnings:

  drivers/rapidio/rio-driver.c:53:16: warning: symbol 'rio_dev_get' was not declared. Should it be static?
  drivers/rapidio/rio-driver.c:70:6: warning: symbol 'rio_dev_put' was not declared. Should it be static?
  drivers/rapidio/rio-driver.c:150:5: warning: symbol 'rio_register_driver' was not declared. Should it be static?
  drivers/rapidio/rio-driver.c:169:6: warning: symbol 'rio_unregister_driver' was not declared. Should it be static?

Link: http://lkml.kernel.org/r/20191017114923.10888-1-ben.dooks@codethink.co.uk
Signed-off-by: Ben Dooks <ben.dooks@codethink.co.uk>
Cc: Matt Porter <mporter@kernel.crashing.org>
Cc: Alexandre Bounine <alex.bou9@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agoinit/Kconfig: fix indentation
Krzysztof Kozlowski [Thu, 5 Dec 2019 00:52:28 +0000 (16:52 -0800)]
init/Kconfig: fix indentation

Adjust indentation from spaces to tab (+optional two spaces) as in
coding style with command like:
$ sed -e 's/^        / /' -i */Kconfig

Link: http://lkml.kernel.org/r/1574306670-30234-1-git-send-email-krzk@kernel.org
Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
Cc: Jiri Kosina <trivial@kernel.org>
Cc: Masahiro Yamada <yamada.masahiro@socionext.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: David Hildenbrand <david@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agofs/binfmt_elf.c: extract elf_read() function
Alexey Dobriyan [Thu, 5 Dec 2019 00:52:25 +0000 (16:52 -0800)]
fs/binfmt_elf.c: extract elf_read() function

ELF reads done by the kernel have very complicated error detection code
which better live in one place.

Link: http://lkml.kernel.org/r/20191005165215.GB26927@avx2
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agofs/binfmt_elf.c: delete unused "interp_map_addr" argument
Alexey Dobriyan [Thu, 5 Dec 2019 00:52:22 +0000 (16:52 -0800)]
fs/binfmt_elf.c: delete unused "interp_map_addr" argument

Link: http://lkml.kernel.org/r/20191005165049.GA26927@avx2
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agoselftests: add epoll selftests
Heiher [Thu, 5 Dec 2019 00:52:19 +0000 (16:52 -0800)]
selftests: add epoll selftests

This adds the promised selftest for epoll.  It will verify the wakeups
of epoll.  Including leaf and nested mode, epoll_wait() and poll() and
multi-threads.

Link: http://lkml.kernel.org/r/20191009121518.4027-1-r@hev.cc
Signed-off-by: hev <r@hev.cc>
Reviewed-by: Roman Penyaev <rpenyaev@suse.de>
Cc: Jason Baron <jbaron@akamai.com>
Cc: Shuah Khan <shuah@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agofs/epoll: remove unnecessary wakeups of nested epoll
Heiher [Thu, 5 Dec 2019 00:52:15 +0000 (16:52 -0800)]
fs/epoll: remove unnecessary wakeups of nested epoll

Take the case where we have:

        t0
         | (ew)
        e0
         | (et)
        e1
         | (lt)
        s0

t0: thread 0
e0: epoll fd 0
e1: epoll fd 1
s0: socket fd 0
ew: epoll_wait
et: edge-trigger
lt: level-trigger

We remove unnecessary wakeups to prevent the nested epoll that working in edge-
triggered mode to waking up continuously.

Test code:
 #include <unistd.h>
 #include <sys/epoll.h>
 #include <sys/socket.h>

 int main(int argc, char *argv[])
 {
  int sfd[2];
  int efd[2];
  struct epoll_event e;

  if (socketpair(AF_UNIX, SOCK_STREAM, 0, sfd) < 0)
  goto out;

  efd[0] = epoll_create(1);
  if (efd[0] < 0)
  goto out;

  efd[1] = epoll_create(1);
  if (efd[1] < 0)
  goto out;

  e.events = EPOLLIN;
  if (epoll_ctl(efd[1], EPOLL_CTL_ADD, sfd[0], &e) < 0)
  goto out;

  e.events = EPOLLIN | EPOLLET;
  if (epoll_ctl(efd[0], EPOLL_CTL_ADD, efd[1], &e) < 0)
  goto out;

  if (write(sfd[1], "w", 1) != 1)
  goto out;

  if (epoll_wait(efd[0], &e, 1, 0) != 1)
  goto out;

  if (epoll_wait(efd[0], &e, 1, 0) != 0)
  goto out;

  close(efd[0]);
  close(efd[1]);
  close(sfd[0]);
  close(sfd[1]);

  return 0;

 out:
  return -1;
 }

More tests:
 https://github.com/heiher/epoll-wakeup

Link: http://lkml.kernel.org/r/20191009060516.3577-1-r@hev.cc
Signed-off-by: hev <r@hev.cc>
Reviewed-by: Roman Penyaev <rpenyaev@suse.de>
Cc: Al Viro <viro@ZenIV.linux.org.uk>
Cc: Davide Libenzi <davidel@xmailserver.org>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: Dominik Brodowski <linux@dominikbrodowski.net>
Cc: Eric Wong <e@80x24.org>
Cc: Jason Baron <jbaron@akamai.com>
Cc: Sridhar Samudrala <sridhar.samudrala@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agoepoll: simplify ep_poll_safewake() for CONFIG_DEBUG_LOCK_ALLOC
Jason Baron [Thu, 5 Dec 2019 00:52:12 +0000 (16:52 -0800)]
epoll: simplify ep_poll_safewake() for CONFIG_DEBUG_LOCK_ALLOC

Currently, ep_poll_safewake() in the CONFIG_DEBUG_LOCK_ALLOC case uses
ep_call_nested() in order to pass the correct subclass argument to
spin_lock_irqsave_nested().  However, ep_call_nested() adds unnecessary
checks for epoll depth and loops that are already verified when doing
EPOLL_CTL_ADD.  This mirrors a conversion that was done for
!CONFIG_DEBUG_LOCK_ALLOC in: commit 37b5e5212a44 ("epoll: remove
ep_call_nested() from ep_eventpoll_poll()")

Link: http://lkml.kernel.org/r/1567628549-11501-1-git-send-email-jbaron@akamai.com
Signed-off-by: Jason Baron <jbaron@akamai.com>
Reviewed-by: Roman Penyaev <rpenyaev@suse.de>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Eric Wong <normalperson@yhbt.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agocheckpatch: reduce is_maintained_obsolete lookup runtime
Joe Perches [Thu, 5 Dec 2019 00:52:09 +0000 (16:52 -0800)]
checkpatch: reduce is_maintained_obsolete lookup runtime

The is_maintained_obsolete function can be called twice using the same
filename.  This function spawns a process using get_maintainer.pl.
Store the status of each filename when spawned and use the stored result
to eliminate the spawning of unnecessary duplicate child processes.

Example:

old:

  $ time ./scripts/checkpatch.pl hp100-Move-to-staging.patch > /dev/null

  real 0m1.767s
  user 0m1.634s
  sys 0m0.141s

new:

  $ time ./scripts/checkpatch.pl hp100-Move-to-staging.patch > /dev/null

  real 0m1.184s
  user 0m1.085s
  sys 0m0.103s

Link: http://lkml.kernel.org/r/b982566a2b9b4825badce36fdfc3032bd0005151.camel@perches.com
Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agocheckpatch: improve ignoring CamelCase SI style variants like mA
Joe Perches [Thu, 5 Dec 2019 00:52:06 +0000 (16:52 -0800)]
checkpatch: improve ignoring CamelCase SI style variants like mA

Ignore all upper-case variants before and after SI units like mA, mV and
uV so uses like RANGE_mA do not emit a CAMELCASE message.

Link: http://lkml.kernel.org/r/5ce6f9131327fd2e12d7a0e20a55f588448de090.camel@perches.com
Signed-off-by: Joe Perches <joe@perches.com>
Cc: Jules Irenge <jbi.octave@gmail.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agolib/genalloc.c: rename addr_in_gen_pool to gen_pool_has_addr
Huang Shijie [Thu, 5 Dec 2019 00:52:03 +0000 (16:52 -0800)]
lib/genalloc.c: rename addr_in_gen_pool to gen_pool_has_addr

Follow the kernel conventions, rename addr_in_gen_pool to
gen_pool_has_addr.

[sjhuang@iluvatar.ai: fix Documentation/ too]
Link: http://lkml.kernel.org/r/20181229015914.5573-1-sjhuang@iluvatar.ai
Link: http://lkml.kernel.org/r/20181228083950.20398-1-sjhuang@iluvatar.ai
Signed-off-by: Huang Shijie <sjhuang@iluvatar.ai>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Marek Szyprowski <m.szyprowski@samsung.com>
Cc: Robin Murphy <robin.murphy@arm.com>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agolib/genalloc.c: export symbol addr_in_gen_pool
Huang Shijie [Thu, 5 Dec 2019 00:52:00 +0000 (16:52 -0800)]
lib/genalloc.c: export symbol addr_in_gen_pool

We use addr_in_gen_pool() in a driver module.  So export it.

Link: http://lkml.kernel.org/r/20181224070622.22197-2-sjhuang@iluvatar.ai
Signed-off-by: Huang Shijie <sjhuang@iluvatar.ai>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Alexey Skidanov <alexey.skidanov@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agolib/math/rational.c: fix possible incorrect result from rational fractions helper
Trent Piepho [Thu, 5 Dec 2019 00:51:57 +0000 (16:51 -0800)]
lib/math/rational.c: fix possible incorrect result from rational fractions helper

In some cases the previous algorithm would not return the closest
approximation.  This would happen when a semi-convergent was the
closest, as the previous algorithm would only consider convergents.

As an example, consider an initial value of 5/4, and trying to find the
closest approximation with a maximum of 4 for numerator and denominator.
The previous algorithm would return 1/1 as the closest approximation,
while this version will return the correct answer of 4/3.

To do this, the main loop performs effectively the same operations as it
did before.  It must now keep track of the last three approximations,
n2/d2 ..  n0/d0, while before it only needed the last two.

If an exact answer is not found, the algorithm will now calculate the
best semi-convergent term, t, which is a single expression with two
divisions:

    min((max_numerator - n0) / n1, (max_denominator - d0) / d1)

This will be used if it is better than previous convergent.  The test
for this is generally a simple comparison, 2*t > a.  But in an edge
case, where the convergent's final term is even and the best allowable
semi-convergent has a final term of exactly half the convergent's final
term, the more complex comparison (d0*dp > d1*d) is used.

I also wrote some comments explaining the code.  While one still needs
to look up the math elsewhere, they should help a lot to follow how the
code relates to that math.

This routine is used in two places in the video4linux code, but in those
cases it is only used to reduce a fraction to lowest terms, which the
existing code will do correctly.  This could be done more efficiently
with a different library routine but it would still be the Euclidean
alogrithm at its heart.  So no change.

The remain users are places where a fractional PLL divider is
programmed.  What would happen is something asked for a clock of X MHz
but instead gets Y MHz, where Y is close to X but not exactly due to the
hardware limitations.  After this change they might, in some cases, get
Y' MHz, where Y' is a little closer to X then Y was.

Users like this are: Three UARTs, in 8250_mid, 8250_lpss, and imx.  One
GPU in vp4_hdmi.  And three clock drivers, clk-cdce706, clk-si5351, and
clk-fractional-divider.  The last is a generic clock driver and so would
have more users referenced via device tree entries.

I think there's a bug in that one, it's limiting an N bit field that is
offset-by-1 to the range 0 ..  (1<<N)-2, when it should be (1<<N)-1 as
the upper limit.

I have an IMX system, one of the UARTs using this, so I can provide a
real example.  If I request a custom baud rate of 1499978, the driver
will program the PLL to produce a baud rate of 1500000.  After this
change, the fractional divider in the UART is programmed to a ratio of
65535/65536, which produces a baud rate of 1499977.0625.  Closer to the
requested value.

Link: http://lkml.kernel.org/r/20190330205855.19396-1-tpiepho@gmail.com
Signed-off-by: Trent Piepho <tpiepho@gmail.com>
Cc: Oskar Schirmer <oskar@scara.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agolib/test_meminit.c: add bulk alloc/free tests
Laura Abbott [Thu, 5 Dec 2019 00:51:53 +0000 (16:51 -0800)]
lib/test_meminit.c: add bulk alloc/free tests

kmem_cache_alloc_bulk/kmem_cache_free_bulk are used to make multiple
allocations of the same size to avoid the overhead of multiple
kmalloc/kfree calls.  Extend the kmem_cache tests to make some calls to
these APIs.

Link: http://lkml.kernel.org/r/20191107191447.23058-1-labbott@redhat.com
Signed-off-by: Laura Abbott <labbott@redhat.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Tested-by: Alexander Potapenko <glider@google.com>
Cc: Laura Abbott <labbott@redhat.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Nick Desaulniers <ndesaulniers@google.com>
Cc: Kostya Serebryany <kcc@google.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Sandeep Patil <sspatil@android.com>
Cc: Jann Horn <jannh@google.com>
Cc: Marco Elver <elver@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agolib/rbtree: get successor's color directly
Wei Yang [Thu, 5 Dec 2019 00:51:50 +0000 (16:51 -0800)]
lib/rbtree: get successor's color directly

After move parent assignment out, we can check the color directly.

Link: http://lkml.kernel.org/r/20191028021442.5450-2-richardw.yang@linux.intel.com
Signed-off-by: Wei Yang <richardw.yang@linux.intel.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Michel Lespinasse <walken@google.com>
Reviewed-by: Davidlohr Bueso <dbueso@suse.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agolib/rbtree: set successor's parent unconditionally
Wei Yang [Thu, 5 Dec 2019 00:51:47 +0000 (16:51 -0800)]
lib/rbtree: set successor's parent unconditionally

Both in Case 2 and 3, we exchange n and s.  This mean no matter whether
child2 is NULL or not, successor's parent should be assigned to node's.

This patch takes this step out to make it explicit and reduce the
ambiguity.

Besides, this step reduces some symbol size like rb_erase().

   KERN_CONFIG       upstream       patched
   OPT_FOR_PERF      877            870
   OPT_FOR_SIZE      635            621

Link: http://lkml.kernel.org/r/20191028021442.5450-1-richardw.yang@linux.intel.com
Signed-off-by: Wei Yang <richardw.yang@linux.intel.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Michel Lespinasse <walken@google.com>
Reviewed-by: Davidlohr Bueso <dbueso@suse.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agogpio: pca953x: utilize the for_each_set_clump8 macro
William Breathitt Gray [Thu, 5 Dec 2019 00:51:43 +0000 (16:51 -0800)]
gpio: pca953x: utilize the for_each_set_clump8 macro

Replace verbose implementation in set_multiple callback with
for_each_set_clump8 macro to simplify code and improve clarity.

Link: http://lkml.kernel.org/r/3543ffc3668ad4ed4c00e8ebaf14a5559fd6ddf2.1570641097.git.vilhelm.gray@gmail.com
Signed-off-by: William Breathitt Gray <vilhelm.gray@gmail.com>
Tested-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Phil Reid <preid@electromag.com.au>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Geert Uytterhoeven <geert+renesas@glider.be>
Cc: Linus Walleij <linus.walleij@linaro.org>
Cc: Lukas Wunner <lukas@wunner.de>
Cc: Masahiro Yamada <yamada.masahiro@socionext.com>
Cc: Mathias Duckeck <m.duckeck@kunbus.de>
Cc: Morten Hein Tiljeset <morten.tiljeset@prevas.dk>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Sean Nyekjaer <sean.nyekjaer@prevas.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agogpio: max3191x: utilize the for_each_set_clump8 macro
William Breathitt Gray [Thu, 5 Dec 2019 00:51:40 +0000 (16:51 -0800)]
gpio: max3191x: utilize the for_each_set_clump8 macro

Replace verbose implementation in get_multiple callback with
for_each_set_clump8 macro to simplify code and improve clarity.

Link: http://lkml.kernel.org/r/c2b1ed62caf6fce6e5681809a50c05ce6acdf2a6.1570641097.git.vilhelm.gray@gmail.com
Signed-off-by: William Breathitt Gray <vilhelm.gray@gmail.com>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Mathias Duckeck <m.duckeck@kunbus.de>
Cc: Lukas Wunner <lukas@wunner.de>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Geert Uytterhoeven <geert+renesas@glider.be>
Cc: Linus Walleij <linus.walleij@linaro.org>
Cc: Masahiro Yamada <yamada.masahiro@socionext.com>
Cc: Morten Hein Tiljeset <morten.tiljeset@prevas.dk>
Cc: Phil Reid <preid@electromag.com.au>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Sean Nyekjaer <sean.nyekjaer@prevas.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agogpio: pisosr: utilize the for_each_set_clump8 macro
William Breathitt Gray [Thu, 5 Dec 2019 00:51:36 +0000 (16:51 -0800)]
gpio: pisosr: utilize the for_each_set_clump8 macro

Replace verbose implementation in get_multiple callback with
for_each_set_clump8 macro to simplify code and improve clarity.

Link: http://lkml.kernel.org/r/8a39ee772247d4b7d752b32dbacc06c1cdcb60b5.1570641097.git.vilhelm.gray@gmail.com
Signed-off-by: William Breathitt Gray <vilhelm.gray@gmail.com>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Morten Hein Tiljeset <morten.tiljeset@prevas.dk>
Cc: Sean Nyekjaer <sean.nyekjaer@prevas.dk>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Geert Uytterhoeven <geert+renesas@glider.be>
Cc: Linus Walleij <linus.walleij@linaro.org>
Cc: Lukas Wunner <lukas@wunner.de>
Cc: Masahiro Yamada <yamada.masahiro@socionext.com>
Cc: Mathias Duckeck <m.duckeck@kunbus.de>
Cc: Phil Reid <preid@electromag.com.au>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agothermal: intel: intel_soc_dts_iosf: Utilize for_each_set_clump8 macro
William Breathitt Gray [Thu, 5 Dec 2019 00:51:32 +0000 (16:51 -0800)]
thermal: intel: intel_soc_dts_iosf: Utilize for_each_set_clump8 macro

Utilize for_each_set_clump8 macro, and the bitmap_set_value8 and
bitmap_get_value8 functions, where appropriate.  In addition, remove the
now unnecessary temp_mask and temp_shift members of the
intel_soc_dts_sensor_entry structure.

Link: http://lkml.kernel.org/r/2d3c74e9a00a52954f31d19e04623a7f4bc85520.1570641097.git.vilhelm.gray@gmail.com
Signed-off-by: William Breathitt Gray <vilhelm.gray@gmail.com>
Suggested-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Geert Uytterhoeven <geert+renesas@glider.be>
Cc: Linus Walleij <linus.walleij@linaro.org>
Cc: Lukas Wunner <lukas@wunner.de>
Cc: Masahiro Yamada <yamada.masahiro@socionext.com>
Cc: Mathias Duckeck <m.duckeck@kunbus.de>
Cc: Morten Hein Tiljeset <morten.tiljeset@prevas.dk>
Cc: Phil Reid <preid@electromag.com.au>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Sean Nyekjaer <sean.nyekjaer@prevas.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agogpio: 74x164: utilize the for_each_set_clump8 macro
William Breathitt Gray [Thu, 5 Dec 2019 00:51:29 +0000 (16:51 -0800)]
gpio: 74x164: utilize the for_each_set_clump8 macro

Replace verbose implementation in set_multiple callback with
for_each_set_clump8 macro to simplify code and improve clarity.

Link: http://lkml.kernel.org/r/7ea2df7182a50a1136ca36edc46dffcb2446fd27.1570641097.git.vilhelm.gray@gmail.com
Signed-off-by: William Breathitt Gray <vilhelm.gray@gmail.com>
Suggested-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Tested-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Geert Uytterhoeven <geert+renesas@glider.be>
Cc: Phil Reid <preid@electromag.com.au>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Linus Walleij <linus.walleij@linaro.org>
Cc: Lukas Wunner <lukas@wunner.de>
Cc: Masahiro Yamada <yamada.masahiro@socionext.com>
Cc: Mathias Duckeck <m.duckeck@kunbus.de>
Cc: Morten Hein Tiljeset <morten.tiljeset@prevas.dk>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Sean Nyekjaer <sean.nyekjaer@prevas.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agogpio: uniphier: utilize for_each_set_clump8 macro
William Breathitt Gray [Thu, 5 Dec 2019 00:51:25 +0000 (16:51 -0800)]
gpio: uniphier: utilize for_each_set_clump8 macro

Replace verbose implementation in set_multiple callback with
for_each_set_clump8 macro to simplify code and improve clarity.  An
improvement in this case is that banks that are not masked will now be
skipped.

Link: http://lkml.kernel.org/r/5b24887e97f3093e4832d7c50a1093f537e91ab4.1570641097.git.vilhelm.gray@gmail.com
Signed-off-by: William Breathitt Gray <vilhelm.gray@gmail.com>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Masahiro Yamada <yamada.masahiro@socionext.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Geert Uytterhoeven <geert+renesas@glider.be>
Cc: Linus Walleij <linus.walleij@linaro.org>
Cc: Lukas Wunner <lukas@wunner.de>
Cc: Mathias Duckeck <m.duckeck@kunbus.de>
Cc: Morten Hein Tiljeset <morten.tiljeset@prevas.dk>
Cc: Phil Reid <preid@electromag.com.au>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Sean Nyekjaer <sean.nyekjaer@prevas.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agogpio: pcie-idio-24: utilize for_each_set_clump8 macro
William Breathitt Gray [Thu, 5 Dec 2019 00:51:22 +0000 (16:51 -0800)]
gpio: pcie-idio-24: utilize for_each_set_clump8 macro

Replace verbose implementation in get_multiple/set_multiple callbacks
with for_each_set_clump8 macro to simplify code and improve clarity.

Link: http://lkml.kernel.org/r/d5d22fa9809dcf8330f4381dbe7e7ca37990e79f.1570641097.git.vilhelm.gray@gmail.com
Signed-off-by: William Breathitt Gray <vilhelm.gray@gmail.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Geert Uytterhoeven <geert+renesas@glider.be>
Cc: Lukas Wunner <lukas@wunner.de>
Cc: Masahiro Yamada <yamada.masahiro@socionext.com>
Cc: Mathias Duckeck <m.duckeck@kunbus.de>
Cc: Morten Hein Tiljeset <morten.tiljeset@prevas.dk>
Cc: Phil Reid <preid@electromag.com.au>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Sean Nyekjaer <sean.nyekjaer@prevas.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agogpio: pci-idio-16: utilize for_each_set_clump8 macro
William Breathitt Gray [Thu, 5 Dec 2019 00:51:18 +0000 (16:51 -0800)]
gpio: pci-idio-16: utilize for_each_set_clump8 macro

Replace verbose implementation in get_multiple/set_multiple callbacks
with for_each_set_clump8 macro to simplify code and improve clarity.

Link: http://lkml.kernel.org/r/b30f131b4634caf5a70f12e01496f71631a17305.1570641097.git.vilhelm.gray@gmail.com
Signed-off-by: William Breathitt Gray <vilhelm.gray@gmail.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Geert Uytterhoeven <geert+renesas@glider.be>
Cc: Lukas Wunner <lukas@wunner.de>
Cc: Masahiro Yamada <yamada.masahiro@socionext.com>
Cc: Mathias Duckeck <m.duckeck@kunbus.de>
Cc: Morten Hein Tiljeset <morten.tiljeset@prevas.dk>
Cc: Phil Reid <preid@electromag.com.au>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Sean Nyekjaer <sean.nyekjaer@prevas.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agogpio: ws16c48: utilize for_each_set_clump8 macro
William Breathitt Gray [Thu, 5 Dec 2019 00:51:15 +0000 (16:51 -0800)]
gpio: ws16c48: utilize for_each_set_clump8 macro

Replace verbose implementation in get_multiple/set_multiple callbacks
with for_each_set_clump8 macro to simplify code and improve clarity.

Link: http://lkml.kernel.org/r/7a0d2c964e7f2d289b16c63ff6b06fc1f4c50d4d.1570641097.git.vilhelm.gray@gmail.com
Signed-off-by: William Breathitt Gray <vilhelm.gray@gmail.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Geert Uytterhoeven <geert+renesas@glider.be>
Cc: Lukas Wunner <lukas@wunner.de>
Cc: Masahiro Yamada <yamada.masahiro@socionext.com>
Cc: Mathias Duckeck <m.duckeck@kunbus.de>
Cc: Morten Hein Tiljeset <morten.tiljeset@prevas.dk>
Cc: Phil Reid <preid@electromag.com.au>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Sean Nyekjaer <sean.nyekjaer@prevas.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agogpio: gpio-mm: utilize for_each_set_clump8 macro
William Breathitt Gray [Thu, 5 Dec 2019 00:51:11 +0000 (16:51 -0800)]
gpio: gpio-mm: utilize for_each_set_clump8 macro

Replace verbose implementation in get_multiple/set_multiple callbacks
with for_each_set_clump8 macro to simplify code and improve clarity.

Link: http://lkml.kernel.org/r/0de53d7021b2d6db10294473cd8a1b6102bcec94.1570641097.git.vilhelm.gray@gmail.com
Signed-off-by: William Breathitt Gray <vilhelm.gray@gmail.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Geert Uytterhoeven <geert+renesas@glider.be>
Cc: Lukas Wunner <lukas@wunner.de>
Cc: Masahiro Yamada <yamada.masahiro@socionext.com>
Cc: Mathias Duckeck <m.duckeck@kunbus.de>
Cc: Morten Hein Tiljeset <morten.tiljeset@prevas.dk>
Cc: Phil Reid <preid@electromag.com.au>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Sean Nyekjaer <sean.nyekjaer@prevas.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agogpio: 104-idi-48: utilize for_each_set_clump8 macro
William Breathitt Gray [Thu, 5 Dec 2019 00:51:08 +0000 (16:51 -0800)]
gpio: 104-idi-48: utilize for_each_set_clump8 macro

Replace verbose implementation in get_multiple/set_multiple callbacks
with for_each_set_clump8 macro to simplify code and improve clarity.

Link: http://lkml.kernel.org/r/b0631b6d489f85008480399df283ccd33ecfe310.1570641097.git.vilhelm.gray@gmail.com
Signed-off-by: William Breathitt Gray <vilhelm.gray@gmail.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Geert Uytterhoeven <geert+renesas@glider.be>
Cc: Lukas Wunner <lukas@wunner.de>
Cc: Masahiro Yamada <yamada.masahiro@socionext.com>
Cc: Mathias Duckeck <m.duckeck@kunbus.de>
Cc: Morten Hein Tiljeset <morten.tiljeset@prevas.dk>
Cc: Phil Reid <preid@electromag.com.au>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Sean Nyekjaer <sean.nyekjaer@prevas.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agogpio: 104-dio-48e: utilize for_each_set_clump8 macro
William Breathitt Gray [Thu, 5 Dec 2019 00:51:04 +0000 (16:51 -0800)]
gpio: 104-dio-48e: utilize for_each_set_clump8 macro

Replace verbose implementation in get_multiple/set_multiple callbacks
with for_each_set_clump8 macro to simplify code and improve clarity.

Link: http://lkml.kernel.org/r/08b9c9a3e75ef1ab0d172223d10a1661f2b43fe2.1570641097.git.vilhelm.gray@gmail.com
Signed-off-by: William Breathitt Gray <vilhelm.gray@gmail.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Geert Uytterhoeven <geert+renesas@glider.be>
Cc: Lukas Wunner <lukas@wunner.de>
Cc: Masahiro Yamada <yamada.masahiro@socionext.com>
Cc: Mathias Duckeck <m.duckeck@kunbus.de>
Cc: Morten Hein Tiljeset <morten.tiljeset@prevas.dk>
Cc: Phil Reid <preid@electromag.com.au>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Sean Nyekjaer <sean.nyekjaer@prevas.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agolib/test_bitmap.c: add for_each_set_clump8 test cases
William Breathitt Gray [Thu, 5 Dec 2019 00:51:01 +0000 (16:51 -0800)]
lib/test_bitmap.c: add for_each_set_clump8 test cases

The introduction of the for_each_set_clump8 macro warrants test cases to
verify the implementation.  This patch adds test case checks for whether
an out-of-bounds clump index is returned, a zero clump is returned, or
the returned clump value differs from the expected clump value.

Link: http://lkml.kernel.org/r/febc0fb8151e3e3fdd61c34da9193d1c4d7e6c12.1570641097.git.vilhelm.gray@gmail.com
Signed-off-by: William Breathitt Gray <vilhelm.gray@gmail.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Tested-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Geert Uytterhoeven <geert+renesas@glider.be>
Cc: Lukas Wunner <lukas@wunner.de>
Cc: Masahiro Yamada <yamada.masahiro@socionext.com>
Cc: Mathias Duckeck <m.duckeck@kunbus.de>
Cc: Morten Hein Tiljeset <morten.tiljeset@prevas.dk>
Cc: Phil Reid <preid@electromag.com.au>
Cc: Sean Nyekjaer <sean.nyekjaer@prevas.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agobitops: introduce the for_each_set_clump8 macro
William Breathitt Gray [Thu, 5 Dec 2019 00:50:57 +0000 (16:50 -0800)]
bitops: introduce the for_each_set_clump8 macro

Pach series "Introduce the for_each_set_clump8 macro", v18.

While adding GPIO get_multiple/set_multiple callback support for various
drivers, I noticed a pattern of looping manifesting that would be useful
standardized as a macro.

This patchset introduces the for_each_set_clump8 macro and utilizes it
in several GPIO drivers.  The for_each_set_clump macro8 facilitates a
for-loop syntax that iterates over a memory region entire groups of set
bits at a time.

For example, suppose you would like to iterate over a 32-bit integer 8
bits at a time, skipping over 8-bit groups with no set bit, where
XXXXXXXX represents the current 8-bit group:

    Example:        10111110 00000000 11111111 00110011
    First loop:     10111110 00000000 11111111 XXXXXXXX
    Second loop:    10111110 00000000 XXXXXXXX 00110011
    Third loop:     XXXXXXXX 00000000 11111111 00110011

Each iteration of the loop returns the next 8-bit group that has at
least one set bit.

The for_each_set_clump8 macro has four parameters:

    * start: set to the bit offset of the current clump
    * clump: set to the current clump value
    * bits: bitmap to search within
    * size: bitmap size in number of bits

In this version of the patchset, the for_each_set_clump macro has been
reimplemented and simplified based on the suggestions provided by Rasmus
Villemoes and Andy Shevchenko in the version 4 submission.

In particular, the function of the for_each_set_clump macro has been
restricted to handle only 8-bit clumps; the drivers that use the
for_each_set_clump macro only handle 8-bit ports so a generic
for_each_set_clump implementation is not necessary.  Thus, a solution
for large clumps (i.e.  those larger than the width of a bitmap word)
can be postponed until a driver appears that actually requires such a
generic for_each_set_clump implementation.

For what it's worth, a semi-generic for_each_set_clump (i.e.  for clumps
smaller than the width of a bitmap word) can be implemented by simply
replacing the hardcoded '8' and '0xFF' instances with respective
variables.  I have not yet had a need for such an implementation, and
since it falls short of a true generic for_each_set_clump function, I
have decided to forgo such an implementation for now.

In addition, the bitmap_get_value8 and bitmap_set_value8 functions are
introduced to get and set 8-bit values respectively.  Their use is based
on the behavior suggested in the patchset version 4 review.

This patch (of 14):

This macro iterates for each 8-bit group of bits (clump) with set bits,
within a bitmap memory region.  For each iteration, "start" is set to
the bit offset of the found clump, while the respective clump value is
stored to the location pointed by "clump".  Additionally, the
bitmap_get_value8 and bitmap_set_value8 functions are introduced to
respectively get and set an 8-bit value in a bitmap memory region.

[gustavo@embeddedor.com: fix potential sign-extension overflow]
Link: http://lkml.kernel.org/r/20191015184657.GA26541@embeddedor
[akpm@linux-foundation.org: s/ULL/UL/, per Joe]
[vilhelm.gray@gmail.com: add for_each_set_clump8 documentation]
Link: http://lkml.kernel.org/r/20191016161825.301082-1-vilhelm.gray@gmail.com
Link: http://lkml.kernel.org/r/893c3b4f03266c9496137cc98ac2b1bd27f92c73.1570641097.git.vilhelm.gray@gmail.com
Signed-off-by: William Breathitt Gray <vilhelm.gray@gmail.com>
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Suggested-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Suggested-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Suggested-by: Lukas Wunner <lukas@wunner.de>
Tested-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Linus Walleij <linus.walleij@linaro.org>
Cc: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Cc: Masahiro Yamada <yamada.masahiro@socionext.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Phil Reid <preid@electromag.com.au>
Cc: Geert Uytterhoeven <geert+renesas@glider.be>
Cc: Mathias Duckeck <m.duckeck@kunbus.de>
Cc: Morten Hein Tiljeset <morten.tiljeset@prevas.dk>
Cc: Sean Nyekjaer <sean.nyekjaer@prevas.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agokernel/sys.c: avoid copying possible padding bytes in copy_to_user
Joe Perches [Thu, 5 Dec 2019 00:50:53 +0000 (16:50 -0800)]
kernel/sys.c: avoid copying possible padding bytes in copy_to_user

Initialization is not guaranteed to zero padding bytes so use an
explicit memset instead to avoid leaking any kernel content in any
possible padding bytes.

Link: http://lkml.kernel.org/r/dfa331c00881d61c8ee51577a082d8bebd61805c.camel@perches.com
Signed-off-by: Joe Perches <joe@perches.com>
Cc: Dan Carpenter <error27@gmail.com>
Cc: Julia Lawall <julia.lawall@lip6.fr>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Kees Cook <keescook@chromium.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agokernel/profile.c: use cpumask_available to check for NULL cpumask
Nathan Chancellor [Thu, 5 Dec 2019 00:50:50 +0000 (16:50 -0800)]
kernel/profile.c: use cpumask_available to check for NULL cpumask

When building with clang + -Wtautological-pointer-compare, these
instances pop up:

  kernel/profile.c:339:6: warning: comparison of array 'prof_cpu_mask' not equal to a null pointer is always true [-Wtautological-pointer-compare]
          if (prof_cpu_mask != NULL)
              ^~~~~~~~~~~~~    ~~~~
  kernel/profile.c:376:6: warning: comparison of array 'prof_cpu_mask' not equal to a null pointer is always true [-Wtautological-pointer-compare]
          if (prof_cpu_mask != NULL)
              ^~~~~~~~~~~~~    ~~~~
  kernel/profile.c:406:26: warning: comparison of array 'prof_cpu_mask' not equal to a null pointer is always true [-Wtautological-pointer-compare]
          if (!user_mode(regs) && prof_cpu_mask != NULL &&
                                ^~~~~~~~~~~~~    ~~~~
  3 warnings generated.

This can be addressed with the cpumask_available helper, introduced in
commit f7e30f01a9e2 ("cpumask: Add helper cpumask_available()") to fix
warnings like this while keeping the code the same.

Link: https://github.com/ClangBuiltLinux/linux/issues/747
Link: http://lkml.kernel.org/r/20191022191957.9554-1-natechancellor@gmail.com
Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agokernel/notifier.c: remove blocking_notifier_chain_cond_register()
Xiaoming Ni [Thu, 5 Dec 2019 00:50:47 +0000 (16:50 -0800)]
kernel/notifier.c: remove blocking_notifier_chain_cond_register()

blocking_notifier_chain_cond_register() does not consider system_booting
state, which is the only difference between this function and
blocking_notifier_cain_register().  This can be a bug and is a piece of
duplicate code.

Delete blocking_notifier_chain_cond_register()

Link: http://lkml.kernel.org/r/1568861888-34045-4-git-send-email-nixiaoming@huawei.com
Signed-off-by: Xiaoming Ni <nixiaoming@huawei.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Anna Schumaker <anna.schumaker@netapp.com>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: Chuck Lever <chuck.lever@oracle.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: J. Bruce Fields <bfields@fieldses.org>
Cc: Jeff Layton <jlayton@kernel.org>
Cc: Nadia Derbey <Nadia.Derbey@bull.net>
Cc: "Paul E. McKenney" <paulmck@kernel.org>
Cc: Sam Protsenko <semen.protsenko@linaro.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Trond Myklebust <trond.myklebust@hammerspace.com>
Cc: Vasily Averin <vvs@virtuozzo.com>
Cc: Viresh Kumar <viresh.kumar@linaro.org>
Cc: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agokernel/notifier.c: remove notifier_chain_cond_register()
Xiaoming Ni [Thu, 5 Dec 2019 00:50:43 +0000 (16:50 -0800)]
kernel/notifier.c: remove notifier_chain_cond_register()

The only difference between notifier_chain_cond_register() and
notifier_chain_register() is the lack of warning hints for duplicate
registrations.  Use notifier_chain_register() instead of
notifier_chain_cond_register() to avoid duplicate code

Link: http://lkml.kernel.org/r/1568861888-34045-3-git-send-email-nixiaoming@huawei.com
Signed-off-by: Xiaoming Ni <nixiaoming@huawei.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Anna Schumaker <anna.schumaker@netapp.com>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: Chuck Lever <chuck.lever@oracle.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: J. Bruce Fields <bfields@fieldses.org>
Cc: Jeff Layton <jlayton@kernel.org>
Cc: Nadia Derbey <Nadia.Derbey@bull.net>
Cc: "Paul E. McKenney" <paulmck@kernel.org>
Cc: Sam Protsenko <semen.protsenko@linaro.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Trond Myklebust <trond.myklebust@hammerspace.com>
Cc: Vasily Averin <vvs@virtuozzo.com>
Cc: Viresh Kumar <viresh.kumar@linaro.org>
Cc: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agokernel/notifier.c: intercept duplicate registrations to avoid infinite loops
Xiaoming Ni [Thu, 5 Dec 2019 00:50:39 +0000 (16:50 -0800)]
kernel/notifier.c: intercept duplicate registrations to avoid infinite loops

Registering the same notifier to a hook repeatedly can cause the hook
list to form a ring or lose other members of the list.

  case1: An infinite loop in notifier_chain_register() can cause soft lockup
          atomic_notifier_chain_register(&test_notifier_list, &test1);
          atomic_notifier_chain_register(&test_notifier_list, &test1);
          atomic_notifier_chain_register(&test_notifier_list, &test2);

  case2: An infinite loop in notifier_chain_register() can cause soft lockup
          atomic_notifier_chain_register(&test_notifier_list, &test1);
          atomic_notifier_chain_register(&test_notifier_list, &test1);
          atomic_notifier_call_chain(&test_notifier_list, 0, NULL);

  case3: lose other hook test2
          atomic_notifier_chain_register(&test_notifier_list, &test1);
          atomic_notifier_chain_register(&test_notifier_list, &test2);
          atomic_notifier_chain_register(&test_notifier_list, &test1);

  case4: Unregister returns 0, but the hook is still in the linked list,
         and it is not really registered. If you call
         notifier_call_chain after ko is unloaded, it will trigger oops.

If the system is configured with softlockup_panic and the same hook is
repeatedly registered on the panic_notifier_list, it will cause a loop
panic.

Add a check in notifier_chain_register(), intercepting duplicate
registrations to avoid infinite loops

Link: http://lkml.kernel.org/r/1568861888-34045-2-git-send-email-nixiaoming@huawei.com
Signed-off-by: Xiaoming Ni <nixiaoming@huawei.com>
Reviewed-by: Vasily Averin <vvs@virtuozzo.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Anna Schumaker <anna.schumaker@netapp.com>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: J. Bruce Fields <bfields@fieldses.org>
Cc: Chuck Lever <chuck.lever@oracle.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Jeff Layton <jlayton@kernel.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Nadia Derbey <Nadia.Derbey@bull.net>
Cc: "Paul E. McKenney" <paulmck@kernel.org>
Cc: Sam Protsenko <semen.protsenko@linaro.org>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Trond Myklebust <trond.myklebust@hammerspace.com>
Cc: Viresh Kumar <viresh.kumar@linaro.org>
Cc: Xiaoming Ni <nixiaoming@huawei.com>
Cc: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agoauxdisplay: charlcd: deduplicate simple_strtoul()
Andy Shevchenko [Thu, 5 Dec 2019 00:50:36 +0000 (16:50 -0800)]
auxdisplay: charlcd: deduplicate simple_strtoul()

Like in commit 8b2303de399f ("serial: core: Fix handling of options
after MMIO address") we may use simple_strtoul() which in comparison to
kstrtoul() can do conversion in-place without additional and unnecessary
code to be written.

Link: http://lkml.kernel.org/r/20190801192904.41087-2-andriy.shevchenko@linux.intel.com
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Cc: Geert Uytterhoeven <geert+renesas@glider.be>
Cc: Mans Rullgard <mans@mansr.com>
Cc: Miguel Ojeda <miguel.ojeda.sandonis@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agokernel.h: update comment about simple_strto<foo>() functions
Andy Shevchenko [Thu, 5 Dec 2019 00:50:32 +0000 (16:50 -0800)]
kernel.h: update comment about simple_strto<foo>() functions

There were discussions in the past about use cases for
simple_strto<foo>() functions and, in some rare cases, they have a
benefit over kstrto<foo>() ones.

Update a comment to reduce confusion about special use cases.

Link: http://lkml.kernel.org/r/20190801192904.41087-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Suggested-by: Miguel Ojeda <miguel.ojeda.sandonis@gmail.com>
Cc: Geert Uytterhoeven <geert+renesas@glider.be>
Cc: Mans Rullgard <mans@mansr.com>
Cc: Petr Mladek <pmladek@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agoscripts/get_maintainer.pl: add signatures from Fixes: <badcommit> lines in commit...
Joe Perches [Thu, 5 Dec 2019 00:50:29 +0000 (16:50 -0800)]
scripts/get_maintainer.pl: add signatures from Fixes: <badcommit> lines in commit message

A Fixes: lines in a commit message generally indicate that a previous
commit was inadequate for whatever reason.

The signers of the previous inadequate commit should also be cc'd on
this new commit so update get_maintainer to find the old commit and add
the original signers.

Link: http://lkml.kernel.org/r/33605b9fc0e0f711236951ae84185a6218acff4f.camel@perches.com
Signed-off-by: Joe Perches <joe@perches.com>
Suggested-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agoarch/Kconfig: fix indentation
Krzysztof Kozlowski [Thu, 5 Dec 2019 00:50:26 +0000 (16:50 -0800)]
arch/Kconfig: fix indentation

Adjust indentation from spaces to tab (+optional two spaces) as in
coding style with command like:
$ sed -e 's/^        / /' -i */Kconfig

Link: http://lkml.kernel.org/r/1574306573-10886-1-git-send-email-krzk@kernel.org
Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
Cc: David Hildenbrand <david@redhat.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jiri Kosina <trivial@kernel.org>
Cc: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agolinux/scc.h: make uapi linux/scc.h self-contained
Masahiro Yamada [Thu, 5 Dec 2019 00:50:23 +0000 (16:50 -0800)]
linux/scc.h: make uapi linux/scc.h self-contained

Userspace cannot compile <linux/scc.h>

    CC      usr/include/linux/scc.h.s
  In file included from <command-line>:32:0:
  usr/include/linux/scc.h:20:20: error: `SIOCDEVPRIVATE' undeclared here (not in a function)
    SIOCSCCRESERVED = SIOCDEVPRIVATE,
                      ^~~~~~~~~~~~~~

Include <linux/sockios.h> to make it self-contained, and add it to the
compile-test coverage.

Link: http://lkml.kernel.org/r/20191108055809.26969-1-yamada.masahiro@socionext.com
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agolinux/build_bug.h: change type to int
Rikard Falkeborn [Thu, 5 Dec 2019 00:50:20 +0000 (16:50 -0800)]
linux/build_bug.h: change type to int

Having BUILD_BUG_ON_ZERO produce a value of type size_t leads to awkward
casts in cases where the result needs to be signed, or of smaller type
than size_t.  To avoid this, cast the value to int instead and rely on
implicit type conversions when a larger or unsigned type is needed.

Link: http://lkml.kernel.org/r/20190811184938.1796-3-rikard.falkeborn@gmail.com
Signed-off-by: Rikard Falkeborn <rikard.falkeborn@gmail.com>
Suggested-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Cc: Joe Perches <joe@perches.com>
Cc: Johannes Berg <johannes@sipsolutions.net>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years ago.gitattributes: use 'dts' diff driver for dts files
Stephen Boyd [Thu, 5 Dec 2019 00:50:17 +0000 (16:50 -0800)]
.gitattributes: use 'dts' diff driver for dts files

Git is gaining support to display the closest node to the diff in the
hunk header via the 'dts' diff driver.  Use that driver for all dts and
dtsi files so we can gain some more context on where the diff is.
Taking a recent commit in the kernel dts files you can see the
difference.

With this patch and an updated git

: diff --git a/arch/arm64/boot/dts/nvidia/tegra194-p2888.dtsi b/arch/arm64/boot/dts/nvidia/tegra194-p2888.dtsi
:  index 62e07e1197cc..4c38426a6969 100644
:  --- a/arch/arm64/boot/dts/nvidia/tegra194-p2888.dtsi
:  +++ b/arch/arm64/boot/dts/nvidia/tegra194-p2888.dtsi
:  @@ -289,5 +289,29 @@ vdd_hdmi: regulator@1 {
:                          gpio = <&gpio TEGRA194_MAIN_GPIO(A, 3) GPIO_ACTIVE_HIGH>;
:                          enable-active-high;
:                  };
:  +
:  +               vdd_3v3_pcie: regulator@2 {
:  +                       compatible = "regulator-fixed";

vs. without this patch

:  diff --git a/arch/arm64/boot/dts/nvidia/tegra194-p2888.dtsi b/arch/arm64/boot/dts/nvidia/tegra194-p2888.dtsi
:  index 62e07e1197cc..4c38426a6969 100644
:  --- a/arch/arm64/boot/dts/nvidia/tegra194-p2888.dtsi
:  +++ b/arch/arm64/boot/dts/nvidia/tegra194-p2888.dtsi
:  @@ -289,5 +289,29 @@
:                          gpio = <&gpio TEGRA194_MAIN_GPIO(A, 3) GPIO_ACTIVE_HIGH>;
:                          enable-active-high;
:                  };
:  +
:  +               vdd_3v3_pcie: regulator@2 {
:  +                       compatible = "regulator-fixed";

You can see that we don't know what the context node is because it isn't
shown after the '@@'.

dts is not released yet but it is staged to be in the next release[1].
One can probably build git from source and try it out.

[1] https://git.kernel.org/pub/scm/git/git.git/commit/?id=d49c2c3466d2c8cb0b3d0a43e6b406b07078fdb1

Link: http://lkml.kernel.org/r/20191004212311.141538-1-swboyd@chromium.org
Signed-off-by: Stephen Boyd <swboyd@chromium.org>
Cc: Rob Herring <robh+dt@kernel.org>
Cc: Randy Dunlap <rdunlap@infradead.org>
Acked-by: Frank Rowand <frowand.list@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agoinclude/linux/sysctl.h: inline braces for ctl_table and ctl_table_header
Alessio Balsini [Thu, 5 Dec 2019 00:50:14 +0000 (16:50 -0800)]
include/linux/sysctl.h: inline braces for ctl_table and ctl_table_header

Fix coding style of "struct ctl_table" and "struct ctl_table_header" to
have inline braces.

Besides the wide use of this proposed cose style, this change helps to
find at a glance the struct definition when navigating the code.

Link: http://lkml.kernel.org/r/20190903154906.188651-1-balsini@android.com
Signed-off-by: Alessio Balsini <balsini@android.com>
Acked-by: Luis Chamberlain <mcgrof@kernel.org>
Cc: Kees Cook <keescook@chromium.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agofs/proc/Kconfig: fix indentation
Krzysztof Kozlowski [Thu, 5 Dec 2019 00:50:11 +0000 (16:50 -0800)]
fs/proc/Kconfig: fix indentation

Adjust indentation from spaces to tab (+optional two spaces) as in
coding style with command like:
        $ sed -e 's/^        / /' -i */Kconfig

[adobriyan@gmail.com: add two spaces where necessary]
Link: http://lkml.kernel.org/r/20191124133936.GA5655@avx2
Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agoinclude/linux/proc_fs.h: fix confusing macro arg name
Miaohe Lin [Thu, 5 Dec 2019 00:50:08 +0000 (16:50 -0800)]
include/linux/proc_fs.h: fix confusing macro arg name

state_size and ops are in the wrong position.

Link: http://lkml.kernel.org/r/20190910021747.11216-1-linmiaohe@huawei.com
Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Aleksa Sarai <cyphar@cyphar.com>
Reviewed-by: Christian Brauner <christian.brauner@ubuntu.com>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agofs/proc/internal.h: shuffle "struct pde_opener"
Alexey Dobriyan [Thu, 5 Dec 2019 00:50:05 +0000 (16:50 -0800)]
fs/proc/internal.h: shuffle "struct pde_opener"

List iteration takes more code than anything else which means embedded
list_head should be the first element of the structure.

Space savings:

add/remove: 0/0 grow/shrink: 0/4 up/down: 0/-18 (-18)
Function                                     old     new   delta
close_pdeo                                   228     227      -1
proc_reg_release                              86      82      -4
proc_entry_rundown                           143     139      -4
proc_reg_open                                298     289      -9

Link: http://lkml.kernel.org/r/20191004234753.GB30246@avx2
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agofs/proc/generic.c: delete useless "len" variable
Alexey Dobriyan [Thu, 5 Dec 2019 00:50:02 +0000 (16:50 -0800)]
fs/proc/generic.c: delete useless "len" variable

Pointer to next '/' encodes length of path element and next start
position.  Subtraction and increment are redundant.

Link: http://lkml.kernel.org/r/20191004234521.GA30246@avx2
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agoproc: change ->nlink under proc_subdir_lock
Alexey Dobriyan [Thu, 5 Dec 2019 00:49:59 +0000 (16:49 -0800)]
proc: change ->nlink under proc_subdir_lock

Currently gluing PDE into global /proc tree is done under lock, but
changing ->nlink is not.  Additionally struct proc_dir_entry::nlink is
not atomic so updates can be lost.

Link: http://lkml.kernel.org/r/20190925202436.GA17388@avx2
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agomm/memory.c: replace is_zero_pfn with is_huge_zero_pmd for thp
Yu Zhao [Thu, 5 Dec 2019 00:49:56 +0000 (16:49 -0800)]
mm/memory.c: replace is_zero_pfn with is_huge_zero_pmd for thp

For hugely mapped thp, we use is_huge_zero_pmd() to check if it's zero
page or not.

We do fill ptes with my_zero_pfn() when we split zero thp pmd, but this
is not what we have in vm_normal_page_pmd() -- pmd_trans_huge_lock()
makes sure of it.

This is a trivial fix for /proc/pid/numa_maps, and AFAIK nobody
complains about it.

Gerald Schaefer asked:
: Maybe the description could also mention the symptom of this bug?
: I would assume that it affects anon/dirty accounting in gather_pte_stats(),
: for huge mappings, if zero page mappings are not correctly recognized.

I came across this while I was looking at the code, so I'm not aware of
any symptom.

Link: http://lkml.kernel.org/r/20191108192629.201556-1-yuzhao@google.com
Signed-off-by: Yu Zhao <yuzhao@google.com>
Acked-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Ralph Campbell <rcampbell@nvidia.com>
Cc: Will Deacon <will@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: "Aneesh Kumar K . V" <aneesh.kumar@linux.ibm.com>
Cc: Dave Airlie <airlied@redhat.com>
Cc: Thomas Hellstrom <thellstrom@vmware.com>
Cc: Souptick Joarder <jrdr.linux@gmail.com>
Cc: Gerald Schaefer <gerald.schaefer@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agomm/memcontrol: use vmstat names for printing statistics
Konstantin Khlebnikov [Thu, 5 Dec 2019 00:49:53 +0000 (16:49 -0800)]
mm/memcontrol: use vmstat names for printing statistics

Use common names from vmstat array when possible.  This gives not much
difference in code size for now, but should help in keeping interfaces
consistent.

  add/remove: 0/2 grow/shrink: 2/0 up/down: 70/-72 (-2)
  Function                                     old     new   delta
  memory_stat_format                           984    1050     +66
  memcg_stat_show                              957     961      +4
  memcg1_event_names                            32       -     -32
  mem_cgroup_lru_names                          40       -     -40
  Total: Before=14485337, After=14485335, chg -0.00%

Link: http://lkml.kernel.org/r/157113012508.453.80391533767219371.stgit@buzz
Signed-off-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Acked-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Vladimir Davydov <vdavydov.dev@gmail.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agomm/vmstat: add helpers to get vmstat item names for each enum type
Konstantin Khlebnikov [Thu, 5 Dec 2019 00:49:50 +0000 (16:49 -0800)]
mm/vmstat: add helpers to get vmstat item names for each enum type

Statistics in vmstat is combined from counters with different structure,
but names for them are merged into one array.

This patch adds trivial helpers to get name for each item:

  const char *zone_stat_name(enum zone_stat_item item);
  const char *numa_stat_name(enum numa_stat_item item);
  const char *node_stat_name(enum node_stat_item item);
  const char *writeback_stat_name(enum writeback_stat_item item);
  const char *vm_event_name(enum vm_event_item item);

Names for enum writeback_stat_item are folded in the middle of
vmstat_text so this patch moves declaration into header to calculate
offset of following items.

Also this patch reuses piece of node stat names for lru list names:

  const char *lru_list_name(enum lru_list lru);

This returns common lru list names: "inactive_anon", "active_anon",
"inactive_file", "active_file", "unevictable".

[khlebnikov@yandex-team.ru: do not use size of vmstat_text as count of /proc/vmstat items]
Link: http://lkml.kernel.org/r/157152151769.4139.15423465513138349343.stgit@buzz
Link: https://lore.kernel.org/linux-mm/cd1c42ae-281f-c8a8-70ac-1d01d417b2e1@infradead.org/T/#u
Link: http://lkml.kernel.org/r/157113012325.453.562783073839432766.stgit@buzz
Signed-off-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Vladimir Davydov <vdavydov.dev@gmail.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: YueHaibing <yuehaibing@huawei.com>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agomm: memcg/slab: wait for !root kmem_cache refcnt killing on root kmem_cache destruction
Roman Gushchin [Thu, 5 Dec 2019 00:49:46 +0000 (16:49 -0800)]
mm: memcg/slab: wait for !root kmem_cache refcnt killing on root kmem_cache destruction

Christian reported a warning like the following obtained during running
some KVM-related tests on s390:

    WARNING: CPU: 8 PID: 208 at lib/percpu-refcount.c:108 percpu_ref_exit+0x50/0x58
    Modules linked in: kvm(-) xt_CHECKSUM xt_MASQUERADE bonding xt_tcpudp ip6t_rpfilter ip6t_REJECT nf_reject_ipv6 ipt_REJECT nf_reject_ipv4 xt_conntrack ip6table_na>
    CPU: 8 PID: 208 Comm: kworker/8:1 Not tainted 5.2.0+ #66
    Hardware name: IBM 2964 NC9 712 (LPAR)
    Workqueue: events sysfs_slab_remove_workfn
    Krnl PSW : 0704e00180000000 0000001529746850 (percpu_ref_exit+0x50/0x58)
               R:0 T:1 IO:1 EX:1 Key:0 M:1 W:0 P:0 AS:3 CC:2 PM:0 RI:0 EA:3
    Krnl GPRS: 00000000ffff8808 0000001529746740 000003f4e30e8e18 0036008100000000
               0000001f00000000 0035008100000000 0000001fb3573ab8 0000000000000000
               0000001fbdb6de00 0000000000000000 0000001529f01328 0000001fb3573b00
               0000001fbb27e000 0000001fbdb69300 000003e009263d00 000003e009263cd0
    Krnl Code: 0000001529746842f0a0000407fe        srp        4(11,%r0),2046,0
               000000152974684847000700            bc         0,1792
              #000000152974684ca7f40001            brc        15,152974684e
              >0000001529746850a7f4fff2            brc        15,1529746834
               0000001529746854: 0707                bcr        0,%r7
               0000001529746856: 0707                bcr        0,%r7
               0000001529746858eb8ff0580024        stmg       %r8,%r15,88(%r15)
               000000152974685ea738ffff            lhi        %r3,-1
    Call Trace:
    ([<000003e009263d00>] 0x3e009263d00)
     [<00000015293252ea>] slab_kmem_cache_release+0x3a/0x70
     [<0000001529b04882>] kobject_put+0xaa/0xe8
     [<000000152918cf28>] process_one_work+0x1e8/0x428
     [<000000152918d1b0>] worker_thread+0x48/0x460
     [<00000015291942c6>] kthread+0x126/0x160
     [<0000001529b22344>] ret_from_fork+0x28/0x30
     [<0000001529b2234c>] kernel_thread_starter+0x0/0x10
    Last Breaking-Event-Address:
     [<000000152974684c>] percpu_ref_exit+0x4c/0x58
    ---[ end trace b035e7da5788eb09 ]---

The problem occurs because kmem_cache_destroy() is called immediately
after deleting of a memcg, so it races with the memcg kmem_cache
deactivation.

flush_memcg_workqueue() at the beginning of kmem_cache_destroy() is
supposed to guarantee that all deactivation processes are finished, but
failed to do so.  It waits for an rcu grace period, after which all
children kmem_caches should be deactivated.  During the deactivation
percpu_ref_kill() is called for non root kmem_cache refcounters, but it
requires yet another rcu grace period to finish the transition to the
atomic (dead) state.

So in a rare case when not all children kmem_caches are destroyed at the
moment when the root kmem_cache is about to be gone, we need to wait
another rcu grace period before destroying the root kmem_cache.

This issue can be triggered only with dynamically created kmem_caches
which are used with memcg accounting.  In this case per-memcg child
kmem_caches are created.  They are deactivated from the cgroup removing
path.  If the destruction of the root kmem_cache is racing with the
removal of the cgroup (both are quite complicated multi-stage
processes), the described issue can occur.  The only known way to
trigger it in the real life, is to unload some kernel module which
creates a dedicated kmem_cache, used from different memory cgroups with
GFP_ACCOUNT flag.  If the unloading happens immediately after calling
rmdir on the corresponding cgroup, there is some chance to trigger the
issue.

Link: http://lkml.kernel.org/r/20191129025011.3076017-1-guro@fb.com
Fixes: f0a3a24b532d ("mm: memcg/slab: rework non-root kmem_cache lifecycle management")
Signed-off-by: Roman Gushchin <guro@fb.com>
Reported-by: Christian Borntraeger <borntraeger@de.ibm.com>
Tested-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: Shakeel Butt <shakeelb@google.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>