openwrt/staging/blogic.git
4 years agogcc-10: avoid shadowing standard library 'free()' in crypto
Linus Torvalds [Sat, 9 May 2020 22:58:04 +0000 (15:58 -0700)]
gcc-10: avoid shadowing standard library 'free()' in crypto

gcc-10 has started warning about conflicting types for a few new
built-in functions, particularly 'free()'.

This results in warnings like:

   crypto/xts.c:325:13: warning: conflicting types for built-in function ‘free’; expected ‘void(void *)’ [-Wbuiltin-declaration-mismatch]

because the crypto layer had its local freeing functions called
'free()'.

Gcc-10 is in the wrong here, since that function is marked 'static', and
thus there is no chance of confusion with any standard library function
namespace.

But the simplest thing to do is to just use a different name here, and
avoid this gcc mis-feature.

[ Side note: gcc knowing about 'free()' is in itself not the
  mis-feature: the semantics of 'free()' are special enough that a
  compiler can validly do special things when seeing it.

  So the mis-feature here is that gcc thinks that 'free()' is some
  restricted name, and you can't shadow it as a local static function.

  Making the special 'free()' semantics be a function attribute rather
  than tied to the name would be the much better model ]

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agogcc-10: disable 'restrict' warning for now
Linus Torvalds [Sat, 9 May 2020 22:45:21 +0000 (15:45 -0700)]
gcc-10: disable 'restrict' warning for now

gcc-10 now warns about passing aliasing pointers to functions that take
restricted pointers.

That's actually a great warning, and if we ever start using 'restrict'
in the kernel, it might be quite useful.  But right now we don't, and it
turns out that the only thing this warns about is an idiom where we have
declared a few functions to be "printf-like" (which seems to make gcc
pick up the restricted pointer thing), and then we print to the same
buffer that we also use as an input.

And people do that as an odd concatenation pattern, with code like this:

    #define sysfs_show_gen_prop(buffer, fmt, ...) \
        snprintf(buffer, PAGE_SIZE, "%s"fmt, buffer, __VA_ARGS__)

where we have 'buffer' as both the destination of the final result, and
as the initial argument.

Yes, it's a bit questionable.  And outside of the kernel, people do have
standard declarations like

    int snprintf( char *restrict buffer, size_t bufsz,
                  const char *restrict format, ... );

where that output buffer is marked as a restrict pointer that cannot
alias with any other arguments.

But in the context of the kernel, that 'use snprintf() to concatenate to
the end result' does work, and the pattern shows up in multiple places.
And we have not marked our own version of snprintf() as taking restrict
pointers, so the warning is incorrect for now, and gcc picks it up on
its own.

If we do start using 'restrict' in the kernel (and it might be a good
idea if people find places where it matters), we'll need to figure out
how to avoid this issue for snprintf and friends.  But in the meantime,
this warning is not useful.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agogcc-10: disable 'stringop-overflow' warning for now
Linus Torvalds [Sat, 9 May 2020 22:40:52 +0000 (15:40 -0700)]
gcc-10: disable 'stringop-overflow' warning for now

This is the final array bounds warning removal for gcc-10 for now.

Again, the warning is good, and we should re-enable all these warnings
when we have converted all the legacy array declaration cases to
flexible arrays. But in the meantime, it's just noise.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agogcc-10: disable 'array-bounds' warning for now
Linus Torvalds [Sat, 9 May 2020 21:52:44 +0000 (14:52 -0700)]
gcc-10: disable 'array-bounds' warning for now

This is another fine warning, related to the 'zero-length-bounds' one,
but hitting the same historical code in the kernel.

Because C didn't historically support flexible array members, we have
code that instead uses a one-sized array, the same way we have cases of
zero-sized arrays.

The one-sized arrays come from either not wanting to use the gcc
zero-sized array extension, or from a slight convenience-feature, where
particularly for strings, the size of the structure now includes the
allocation for the final NUL character.

So with a "char name[1];" at the end of a structure, you can do things
like

       v = my_malloc(sizeof(struct vendor) + strlen(name));

and avoid the "+1" for the terminator.

Yes, the modern way to do that is with a flexible array, and using
'offsetof()' instead of 'sizeof()', and adding the "+1" by hand.  That
also technically gets the size "more correct" in that it avoids any
alignment (and thus padding) issues, but this is another long-term
cleanup thing that will not happen for 5.7.

So disable the warning for now, even though it's potentially quite
useful.  Having a slew of warnings that then hide more urgent new issues
is not an improvement.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agogcc-10: disable 'zero-length-bounds' warning for now
Linus Torvalds [Sat, 9 May 2020 21:30:29 +0000 (14:30 -0700)]
gcc-10: disable 'zero-length-bounds' warning for now

This is a fine warning, but we still have a number of zero-length arrays
in the kernel that come from the traditional gcc extension.  Yes, they
are getting converted to flexible arrays, but in the meantime the gcc-10
warning about zero-length bounds is very verbose, and is hiding other
issues.

I missed one actual build failure because it was hidden among hundreds
of lines of warning.  Thankfully I caught it on the second go before
pushing things out, but it convinced me that I really need to disable
the new warnings for now.

We'll hopefully be all done with our conversion to flexible arrays in
the not too distant future, and we can then re-enable this warning.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agoStop the ad-hoc games with -Wno-maybe-initialized
Linus Torvalds [Sat, 9 May 2020 20:57:10 +0000 (13:57 -0700)]
Stop the ad-hoc games with -Wno-maybe-initialized

We have some rather random rules about when we accept the
"maybe-initialized" warnings, and when we don't.

For example, we consider it unreliable for gcc versions < 4.9, but also
if -O3 is enabled, or if optimizing for size.  And then various kernel
config options disabled it, because they know that they trigger that
warning by confusing gcc sufficiently (ie PROFILE_ALL_BRANCHES).

And now gcc-10 seems to be introducing a lot of those warnings too, so
it falls under the same heading as 4.9 did.

At the same time, we have a very straightforward way to _enable_ that
warning when wanted: use "W=2" to enable more warnings.

So stop playing these ad-hoc games, and just disable that warning by
default, with the known and straight-forward "if you want to work on the
extra compiler warnings, use W=123".

Would it be great to have code that is always so obvious that it never
confuses the compiler whether a variable is used initialized or not?
Yes, it would.  In a perfect world, the compilers would be smarter, and
our source code would be simpler.

That's currently not the world we live in, though.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agoMerge tag 'io_uring-5.7-2020-05-08' of git://git.kernel.dk/linux-block
Linus Torvalds [Sat, 9 May 2020 19:02:09 +0000 (12:02 -0700)]
Merge tag 'io_uring-5.7-2020-05-08' of git://git.kernel.dk/linux-block

Pull io_uring fixes from Jens Axboe:

 - Fix finish_wait() balancing in file cancelation (Xiaoguang)

 - Ensure early cleanup of resources in ring map failure (Xiaoguang)

 - Ensure IORING_OP_SLICE does the right file mode checks (Pavel)

 - Remove file opening from openat/openat2/statx, it's not needed and
   messes with O_PATH

* tag 'io_uring-5.7-2020-05-08' of git://git.kernel.dk/linux-block:
  io_uring: don't use 'fd' for openat/openat2/statx
  splice: move f_mode checks to do_{splice,tee}()
  io_uring: handle -EFAULT properly in io_uring_setup()
  io_uring: fix mismatched finish_wait() calls in io_uring_cancel_files()

4 years agoMerge tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi
Linus Torvalds [Fri, 8 May 2020 17:36:56 +0000 (10:36 -0700)]
Merge tag 'scsi-fixes' of git://git./linux/kernel/git/jejb/scsi

Pull SCSI fixes from James Bottomley:
 "Four minor fixes, all in drivers (qla2xxx, ibmvfc, ibmvscsi)"

* tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi:
  scsi: ibmvscsi: Fix WARN_ON during event pool release
  scsi: ibmvfc: Don't send implicit logouts prior to NPIV login
  scsi: qla2xxx: Delete all sessions before unregister local nvme port
  scsi: qla2xxx: Fix hang when issuing nvme disconnect-all in NPIV

4 years agoMerge tag 'ceph-for-5.7-rc5' of git://github.com/ceph/ceph-client
Linus Torvalds [Fri, 8 May 2020 17:27:00 +0000 (10:27 -0700)]
Merge tag 'ceph-for-5.7-rc5' of git://github.com/ceph/ceph-client

Pull ceph fixes from Ilya Dryomov:
 "Fixes for an endianness handling bug that prevented mounts on
  big-endian arches, a spammy log message and a couple error paths.

  Also included a MAINTAINERS update"

* tag 'ceph-for-5.7-rc5' of git://github.com/ceph/ceph-client:
  ceph: demote quotarealm lookup warning to a debug message
  MAINTAINERS: remove myself as ceph co-maintainer
  ceph: fix double unlock in handle_cap_export()
  ceph: fix special error code in ceph_try_get_caps()
  ceph: fix endianness bug when handling MDS session feature bits

4 years agoceph: demote quotarealm lookup warning to a debug message
Luis Henriques [Tue, 5 May 2020 12:59:02 +0000 (13:59 +0100)]
ceph: demote quotarealm lookup warning to a debug message

A misconfigured cephx can easily result in having the kernel client
flooding the logs with:

  ceph: Can't lookup inode 1 (err: -13)

Change this message to debug level.

Cc: stable@vger.kernel.org
URL: https://tracker.ceph.com/issues/44546
Signed-off-by: Luis Henriques <lhenriques@suse.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
4 years agoMerge tag 'char-misc-5.7-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh...
Linus Torvalds [Fri, 8 May 2020 16:11:53 +0000 (09:11 -0700)]
Merge tag 'char-misc-5.7-rc5' of git://git./linux/kernel/git/gregkh/char-misc

Pull char/misc driver fixes from Greg KH:
 "Here are some small driver fixes for 5.7-rc5 that resolve a number of
  minor reported issues:

   - mhi bus driver fixes found as people actually use the code

   - phy driver fixes and compat string additions

   - most driver fix due to link order changing when the core moved out
     of staging

   - mei driver fix

   - interconnect build warning fix

  All of these have been in linux-next for a while with no reported
  issues"

* tag 'char-misc-5.7-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc:
  bus: mhi: core: Fix channel device name conflict
  bus: mhi: core: Fix typo in comment
  bus: mhi: core: Offload register accesses to the controller
  bus: mhi: core: Remove link_status() callback
  bus: mhi: core: Make sure to powerdown if mhi_sync_power_up fails
  bus: mhi: Fix parsing of mhi_flags
  mei: me: disable mei interface on LBG servers.
  phy: qualcomm: usb-hs-28nm: Prepare clocks in init
  MAINTAINERS: Add Vinod Koul as Generic PHY co-maintainer
  interconnect: qcom: Move the static keyword to the front of declaration
  most: core: use function subsys_initcall()
  bus: mhi: core: Fix a NULL vs IS_ERR check in mhi_create_devices()
  phy: qcom-qusb2: Re add "qcom,sdm845-qusb2-phy" compat string
  phy: tegra: Select USB_COMMON for usb_get_maximum_speed()

4 years agoMerge tag 'driver-core-5.7-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git...
Linus Torvalds [Fri, 8 May 2020 16:06:34 +0000 (09:06 -0700)]
Merge tag 'driver-core-5.7-rc5' of git://git./linux/kernel/git/gregkh/driver-core

Pull driver core fixes from Greg KH:
 "Here are a number of small driver core fixes for 5.7-rc5 to resolve a
  bunch of reported issues with the current tree.

  Biggest here are the reverts and patches from John Stultz to resolve a
  bunch of deferred probe regressions we have been seeing in 5.7-rc
  right now.

  Along with those are some other smaller fixes:

   - coredump crash fix

   - devlink fix for when permissive mode was enabled

   - amba and platform device dma_parms fixes

   - component error silenced for when deferred probe happens

  All of these have been in linux-next for a while with no reported
  issues"

* tag 'driver-core-5.7-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core:
  regulator: Revert "Use driver_deferred_probe_timeout for regulator_init_complete_work"
  driver core: Ensure wait_for_device_probe() waits until the deferred_probe_timeout fires
  driver core: Use dev_warn() instead of dev_WARN() for deferred_probe_timeout warnings
  driver core: Revert default driver_deferred_probe_timeout value to 0
  component: Silence bind error on -EPROBE_DEFER
  driver core: Fix handling of fw_devlink=permissive
  coredump: fix crash when umh is disabled
  amba: Initialize dma_parms for amba devices
  driver core: platform: Initialize dma_parms for platform devices

4 years agoMerge tag 'staging-5.7-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh...
Linus Torvalds [Fri, 8 May 2020 16:03:49 +0000 (09:03 -0700)]
Merge tag 'staging-5.7-rc5' of git://git./linux/kernel/git/gregkh/staging

Pull staging driver fixes from Greg KH:
 "Here are three small driver fixes for 5.7-rc5.

  Two of these are documentation fixes:

   - MAINTAINERS update due to removed driver

   - removing Wolfram from the ks7010 driver TODO file

  The other patch is a real fix:

   - fix gasket driver to proper check the return value of a call

  All of these have been in linux-next for a while with no reported
  issues"

* tag 'staging-5.7-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging:
  staging: gasket: Check the return value of gasket_get_bar_index()
  staging: ks7010: remove me from CC list
  MAINTAINERS: remove entry after hp100 driver removal

4 years agoMerge tag 'tty-5.7-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty
Linus Torvalds [Fri, 8 May 2020 15:56:16 +0000 (08:56 -0700)]
Merge tag 'tty-5.7-rc5' of git://git./linux/kernel/git/gregkh/tty

Pull tty/serial fixes from Greg KH:
 "Here are three small TTY/Serial/VT fixes for 5.7-rc5:

   - revert for the bcm63xx driver "fix" that was incorrect

   - vt unicode console bugfix

   - xilinx_uartps console driver fix

  All of these have been in linux next with no reported issues"

* tag 'tty-5.7-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty:
  tty: xilinx_uartps: Fix missing id assignment to the console
  vt: fix unicode console freeing with a common interface
  Revert "tty: serial: bcm63xx: fix missing clk_put() in bcm63xx_uart"

4 years agoMerge tag 'usb-5.7-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb
Linus Torvalds [Fri, 8 May 2020 15:54:00 +0000 (08:54 -0700)]
Merge tag 'usb-5.7-rc5' of git://git./linux/kernel/git/gregkh/usb

Pull USB fixes from Greg KH:
 "Here are some small USB fixes for 5.7-rc5 to resolve some reported
  issues:

   - syzbot found problems fixed

   - usbfs dma mapping fix

   - typec bugfixs

   - chipidea bugfix

   - usb4/thunderbolt fix

   - new device ids/quirks

  All of these have been in linux-next for a while with no reported
  issues"

* tag 'usb-5.7-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb:
  usb: chipidea: msm: Ensure proper controller reset using role switch API
  usb: typec: mux: intel: Handle alt mode HPD_HIGH
  usb: usbfs: correct kernel->user page attribute mismatch
  usb: typec: intel_pmc_mux: Fix the property names
  USB: core: Fix misleading driver bug report
  USB: serial: qcserial: Add DW5816e support
  USB: uas: add quirk for LaCie 2Big Quadra
  thunderbolt: Check return value of tb_sw_read() in usb4_switch_op()
  USB: serial: garmin_gps: add sanity checking for data length

4 years agoMerge tag 'drm-fixes-2020-05-08' of git://anongit.freedesktop.org/drm/drm
Linus Torvalds [Fri, 8 May 2020 15:49:34 +0000 (08:49 -0700)]
Merge tag 'drm-fixes-2020-05-08' of git://anongit.freedesktop.org/drm/drm

Pull drm fixes from Dave Airlie:
 "Another pretty normal week. I didn't get any i915 fixes yet, so next
  week I'd expect double the usual i915, but otherwise a bunch of amdgpu
  and some scattered other fixes.

  hdcp:
   - fix HDCP regression

  amdgpu:
   - Runtime PM fixes
   - DC fix for PPC
   - Misc DC fixes

  virtio:
   - fix context ordering issue

  sun4i:
   - old gcc warning fix

  ingenic-drm:
   - missing module support"

* tag 'drm-fixes-2020-05-08' of git://anongit.freedesktop.org/drm/drm:
  drm/amd/display: Prevent dpcd reads with passive dongles
  drm/amd/display: fix counter in wait_for_no_pipes_pending
  drm/amd/display: Update DCN2.1 DV Code Revision
  drm: Fix HDCP failures when SRM fw is missing
  sun6i: dsi: fix gcc-4.8
  drm: ingenic-drm: add MODULE_DEVICE_TABLE
  drm/virtio: create context before RESOURCE_CREATE_2D in 3D mode
  drm/amd/display: work around fp code being emitted outside of DC_FP_START/END
  drm/amdgpu/dc: Use WARN_ON_ONCE for ASSERT
  drm/amdgpu: drop redundant cg/pg ungate on runpm enter
  drm/amdgpu: move kfd suspend after ip_suspend_phase1

4 years agoMerge branch 'akpm' (patches from Andrew)
Linus Torvalds [Fri, 8 May 2020 15:41:09 +0000 (08:41 -0700)]
Merge branch 'akpm' (patches from Andrew)

Merge misc fixes from Andrew Morton:
 "14 fixes and one selftest to verify the ipc fixes herein"

* emailed patches from Andrew Morton <akpm@linux-foundation.org>:
  mm: limit boost_watermark on small zones
  ubsan: disable UBSAN_ALIGNMENT under COMPILE_TEST
  mm/vmscan: remove unnecessary argument description of isolate_lru_pages()
  epoll: atomically remove wait entry on wake up
  kselftests: introduce new epoll60 testcase for catching lost wakeups
  percpu: make pcpu_alloc() aware of current gfp context
  mm/slub: fix incorrect interpretation of s->offset
  scripts/gdb: repair rb_first() and rb_last()
  eventpoll: fix missing wakeup for ovflist in ep_poll_callback
  arch/x86/kvm/svm/sev.c: change flag passed to GUP fast in sev_pin_memory()
  scripts/decodecode: fix trapping instruction formatting
  kernel/kcov.c: fix typos in kcov_remote_start documentation
  mm/page_alloc: fix watchdog soft lockups during set_zone_contiguous()
  mm, memcg: fix error return value of mem_cgroup_css_alloc()
  ipc/mqueue.c: change __do_notify() to bypass check_kill_permission()

4 years agoMerge tag 'drm-misc-fixes-2020-05-07' of git://anongit.freedesktop.org/drm/drm-misc...
Dave Airlie [Fri, 8 May 2020 05:02:49 +0000 (15:02 +1000)]
Merge tag 'drm-misc-fixes-2020-05-07' of git://anongit.freedesktop.org/drm/drm-misc into drm-fixes

A few minor fixes for an ordering issue in virtio, an (old) gcc warning
in sun4i, a probe issue in ingenic-drm and a regression in the HDCP
support.

Signed-off-by: Dave Airlie <airlied@redhat.com>
From: Maxime Ripard <maxime@cerno.tech>
Link: https://patchwork.freedesktop.org/patch/msgid/20200507160130.id64niqgf5wsha4u@gilmour.lan
4 years agoMerge tag 'amd-drm-fixes-5.7-2020-05-06' of git://people.freedesktop.org/~agd5f/linux...
Dave Airlie [Fri, 8 May 2020 03:31:38 +0000 (13:31 +1000)]
Merge tag 'amd-drm-fixes-5.7-2020-05-06' of git://people.freedesktop.org/~agd5f/linux into drm-fixes

amd-drm-fixes-5.7-2020-05-06:

amdgpu:
- Runtime PM fixes
- DC fix for PPC
- Misc DC fixes

Signed-off-by: Dave Airlie <airlied@redhat.com>
From: Alex Deucher <alexdeucher@gmail.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200506212257.3893-1-alexander.deucher@amd.com
4 years agoMerge branch 'for-v5.7' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris...
Linus Torvalds [Fri, 8 May 2020 02:43:13 +0000 (19:43 -0700)]
Merge branch 'for-v5.7' of git://git./linux/kernel/git/jmorris/linux-security

Pull security subsystem fix from James Morris:
 "Fix the default value of fs_context_parse_param hook"

* 'for-v5.7' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security:
  security: Fix the default value of fs_context_parse_param hook

4 years agomm: limit boost_watermark on small zones
Henry Willard [Fri, 8 May 2020 01:36:27 +0000 (18:36 -0700)]
mm: limit boost_watermark on small zones

Commit 1c30844d2dfe ("mm: reclaim small amounts of memory when an
external fragmentation event occurs") adds a boost_watermark() function
which increases the min watermark in a zone by at least
pageblock_nr_pages or the number of pages in a page block.

On Arm64, with 64K pages and 512M huge pages, this is 8192 pages or
512M.  It does this regardless of the number of managed pages managed in
the zone or the likelihood of success.

This can put the zone immediately under water in terms of allocating
pages from the zone, and can cause a small machine to fail immediately
due to OoM.  Unlike set_recommended_min_free_kbytes(), which
substantially increases min_free_kbytes and is tied to THP,
boost_watermark() can be called even if THP is not active.

The problem is most likely to appear on architectures such as Arm64
where pageblock_nr_pages is very large.

It is desirable to run the kdump capture kernel in as small a space as
possible to avoid wasting memory.  In some architectures, such as Arm64,
there are restrictions on where the capture kernel can run, and
therefore, the space available.  A capture kernel running in 768M can
fail due to OoM immediately after boost_watermark() sets the min in zone
DMA32, where most of the memory is, to 512M.  It fails even though there
is over 500M of free memory.  With boost_watermark() suppressed, the
capture kernel can run successfully in 448M.

This patch limits boost_watermark() to boosting a zone's min watermark
only when there are enough pages that the boost will produce positive
results.  In this case that is estimated to be four times as many pages
as pageblock_nr_pages.

Mel said:

: There is no harm in marking it stable.  Clearly it does not happen very
: often but it's not impossible.  32-bit x86 is a lot less common now
: which would previously have been vulnerable to triggering this easily.
: ppc64 has a larger base page size but typically only has one zone.
: arm64 is likely the most vulnerable, particularly when CMA is
: configured with a small movable zone.

Fixes: 1c30844d2dfe ("mm: reclaim small amounts of memory when an external fragmentation event occurs")
Signed-off-by: Henry Willard <henry.willard@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: David Hildenbrand <david@redhat.com>
Acked-by: Mel Gorman <mgorman@techsingularity.net>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: <stable@vger.kernel.org>
Link: http://lkml.kernel.org/r/1588294148-6586-1-git-send-email-henry.willard@oracle.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agoubsan: disable UBSAN_ALIGNMENT under COMPILE_TEST
Kees Cook [Fri, 8 May 2020 01:36:23 +0000 (18:36 -0700)]
ubsan: disable UBSAN_ALIGNMENT under COMPILE_TEST

The documentation for UBSAN_ALIGNMENT already mentions that it should
not be used on all*config builds (and for efficient-unaligned-access
architectures), so just refactor the Kconfig to correctly implement this
so randconfigs will stop creating insane images that freak out objtool
under CONFIG_UBSAN_TRAP (due to the false positives producing functions
that never return, etc).

Link: http://lkml.kernel.org/r/202005011433.C42EA3E2D@keescook
Fixes: 0887a7ebc977 ("ubsan: add trap instrumentation option")
Signed-off-by: Kees Cook <keescook@chromium.org>
Reported-by: Randy Dunlap <rdunlap@infradead.org>
Link: https://lore.kernel.org/linux-next/202004231224.D6B3B650@keescook/
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agomm/vmscan: remove unnecessary argument description of isolate_lru_pages()
Qiwu Chen [Fri, 8 May 2020 01:36:20 +0000 (18:36 -0700)]
mm/vmscan: remove unnecessary argument description of isolate_lru_pages()

Since commit a9e7c39fa9fd9 ("mm/vmscan.c: remove 7th argument of
isolate_lru_pages()"), the explanation of 'mode' argument has been
unnecessary.  Let's remove it.

Signed-off-by: Qiwu Chen <chenqiwu@xiaomi.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Link: http://lkml.kernel.org/r/20200501090346.2894-1-chenqiwu@xiaomi.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agoepoll: atomically remove wait entry on wake up
Roman Penyaev [Fri, 8 May 2020 01:36:16 +0000 (18:36 -0700)]
epoll: atomically remove wait entry on wake up

This patch does two things:

 - fixes a lost wakeup introduced by commit 339ddb53d373 ("fs/epoll:
   remove unnecessary wakeups of nested epoll")

 - improves performance for events delivery.

The description of the problem is the following: if N (>1) threads are
waiting on ep->wq for new events and M (>1) events come, it is quite
likely that >1 wakeups hit the same wait queue entry, because there is
quite a big window between __add_wait_queue_exclusive() and the
following __remove_wait_queue() calls in ep_poll() function.

This can lead to lost wakeups, because thread, which was woken up, can
handle not all the events in ->rdllist.  (in better words the problem is
described here: https://lkml.org/lkml/2019/10/7/905)

The idea of the current patch is to use init_wait() instead of
init_waitqueue_entry().

Internally init_wait() sets autoremove_wake_function as a callback,
which removes the wait entry atomically (under the wq locks) from the
list, thus the next coming wakeup hits the next wait entry in the wait
queue, thus preventing lost wakeups.

Problem is very well reproduced by the epoll60 test case [1].

Wait entry removal on wakeup has also performance benefits, because
there is no need to take a ep->lock and remove wait entry from the queue
after the successful wakeup.  Here is the timing output of the epoll60
test case:

  With explicit wakeup from ep_scan_ready_list() (the state of the
  code prior 339ddb53d373):

    real    0m6.970s
    user    0m49.786s
    sys     0m0.113s

 After this patch:

   real    0m5.220s
   user    0m36.879s
   sys     0m0.019s

The other testcase is the stress-epoll [2], where one thread consumes
all the events and other threads produce many events:

  With explicit wakeup from ep_scan_ready_list() (the state of the
  code prior 339ddb53d373):

    threads  events/ms  run-time ms
          8       5427         1474
         16       6163         2596
         32       6824         4689
         64       7060         9064
        128       6991        18309

 After this patch:

    threads  events/ms  run-time ms
          8       5598         1429
         16       7073         2262
         32       7502         4265
         64       7640         8376
        128       7634        16767

 (number of "events/ms" represents event bandwidth, thus higher is
  better; number of "run-time ms" represents overall time spent
  doing the benchmark, thus lower is better)

[1] tools/testing/selftests/filesystems/epoll/epoll_wakeup_test.c
[2] https://github.com/rouming/test-tools/blob/master/stress-epoll.c

Signed-off-by: Roman Penyaev <rpenyaev@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Jason Baron <jbaron@akamai.com>
Cc: Khazhismel Kumykov <khazhy@google.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Heiher <r@hev.cc>
Cc: <stable@vger.kernel.org>
Link: http://lkml.kernel.org/r/20200430130326.1368509-2-rpenyaev@suse.de
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agokselftests: introduce new epoll60 testcase for catching lost wakeups
Roman Penyaev [Fri, 8 May 2020 01:36:13 +0000 (18:36 -0700)]
kselftests: introduce new epoll60 testcase for catching lost wakeups

This test case catches lost wake up introduced by commit 339ddb53d373
("fs/epoll: remove unnecessary wakeups of nested epoll")

The test is simple: we have 10 threads and 10 event fds.  Each thread
can harvest only 1 event.  1 producer fires all 10 events at once and
waits that all 10 events will be observed by 10 threads.

In case of lost wakeup epoll_wait() will timeout and 0 will be returned.

Test case catches two sort of problems: forgotten wakeup on event, which
hits the ->ovflist list, this problem was fixed by:

  5a2513239750 ("eventpoll: fix missing wakeup for ovflist in ep_poll_callback")

the other problem is when several sequential events hit the same waiting
thread, thus other waiters get no wakeups.  Problem is fixed in the
following patch.

Signed-off-by: Roman Penyaev <rpenyaev@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Khazhismel Kumykov <khazhy@google.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Heiher <r@hev.cc>
Cc: Jason Baron <jbaron@akamai.com>
Link: http://lkml.kernel.org/r/20200430130326.1368509-1-rpenyaev@suse.de
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agopercpu: make pcpu_alloc() aware of current gfp context
Filipe Manana [Fri, 8 May 2020 01:36:10 +0000 (18:36 -0700)]
percpu: make pcpu_alloc() aware of current gfp context

Since 5.7-rc1, on btrfs we have a percpu counter initialization for
which we always pass a GFP_KERNEL gfp_t argument (this happens since
commit 2992df73268f78 ("btrfs: Implement DREW lock")).

That is safe in some contextes but not on others where allowing fs
reclaim could lead to a deadlock because we are either holding some
btrfs lock needed for a transaction commit or holding a btrfs
transaction handle open.  Because of that we surround the call to the
function that initializes the percpu counter with a NOFS context using
memalloc_nofs_save() (this is done at btrfs_init_fs_root()).

However it turns out that this is not enough to prevent a possible
deadlock because percpu_alloc() determines if it is in an atomic context
by looking exclusively at the gfp flags passed to it (GFP_KERNEL in this
case) and it is not aware that a NOFS context is set.

Because percpu_alloc() thinks it is in a non atomic context it locks the
pcpu_alloc_mutex.  This can result in a btrfs deadlock when
pcpu_balance_workfn() is running, has acquired that mutex and is waiting
for reclaim, while the btrfs task that called percpu_counter_init() (and
therefore percpu_alloc()) is holding either the btrfs commit_root
semaphore or a transaction handle (done fs/btrfs/backref.c:
iterate_extent_inodes()), which prevents reclaim from finishing as an
attempt to commit the current btrfs transaction will deadlock.

Lockdep reports this issue with the following trace:

  ======================================================
  WARNING: possible circular locking dependency detected
  5.6.0-rc7-btrfs-next-77 #1 Not tainted
  ------------------------------------------------------
  kswapd0/91 is trying to acquire lock:
  ffff8938a3b3fdc8 (&delayed_node->mutex){+.+.}, at: __btrfs_release_delayed_node.part.0+0x3f/0x320 [btrfs]

  but task is already holding lock:
  ffffffffb4f0dbc0 (fs_reclaim){+.+.}, at: __fs_reclaim_acquire+0x5/0x30

  which lock already depends on the new lock.

  the existing dependency chain (in reverse order) is:

  -> #4 (fs_reclaim){+.+.}:
         fs_reclaim_acquire.part.0+0x25/0x30
         __kmalloc+0x5f/0x3a0
         pcpu_create_chunk+0x19/0x230
         pcpu_balance_workfn+0x56a/0x680
         process_one_work+0x235/0x5f0
         worker_thread+0x50/0x3b0
         kthread+0x120/0x140
         ret_from_fork+0x3a/0x50

  -> #3 (pcpu_alloc_mutex){+.+.}:
         __mutex_lock+0xa9/0xaf0
         pcpu_alloc+0x480/0x7c0
         __percpu_counter_init+0x50/0xd0
         btrfs_drew_lock_init+0x22/0x70 [btrfs]
         btrfs_get_fs_root+0x29c/0x5c0 [btrfs]
         resolve_indirect_refs+0x120/0xa30 [btrfs]
         find_parent_nodes+0x50b/0xf30 [btrfs]
         btrfs_find_all_leafs+0x60/0xb0 [btrfs]
         iterate_extent_inodes+0x139/0x2f0 [btrfs]
         iterate_inodes_from_logical+0xa1/0xe0 [btrfs]
         btrfs_ioctl_logical_to_ino+0xb4/0x190 [btrfs]
         btrfs_ioctl+0x165a/0x3130 [btrfs]
         ksys_ioctl+0x87/0xc0
         __x64_sys_ioctl+0x16/0x20
         do_syscall_64+0x5c/0x260
         entry_SYSCALL_64_after_hwframe+0x49/0xbe

  -> #2 (&fs_info->commit_root_sem){++++}:
         down_write+0x38/0x70
         btrfs_cache_block_group+0x2ec/0x500 [btrfs]
         find_free_extent+0xc6a/0x1600 [btrfs]
         btrfs_reserve_extent+0x9b/0x180 [btrfs]
         btrfs_alloc_tree_block+0xc1/0x350 [btrfs]
         alloc_tree_block_no_bg_flush+0x4a/0x60 [btrfs]
         __btrfs_cow_block+0x122/0x5a0 [btrfs]
         btrfs_cow_block+0x106/0x240 [btrfs]
         commit_cowonly_roots+0x55/0x310 [btrfs]
         btrfs_commit_transaction+0x509/0xb20 [btrfs]
         sync_filesystem+0x74/0x90
         generic_shutdown_super+0x22/0x100
         kill_anon_super+0x14/0x30
         btrfs_kill_super+0x12/0x20 [btrfs]
         deactivate_locked_super+0x31/0x70
         cleanup_mnt+0x100/0x160
         task_work_run+0x93/0xc0
         exit_to_usermode_loop+0xf9/0x100
         do_syscall_64+0x20d/0x260
         entry_SYSCALL_64_after_hwframe+0x49/0xbe

  -> #1 (&space_info->groups_sem){++++}:
         down_read+0x3c/0x140
         find_free_extent+0xef6/0x1600 [btrfs]
         btrfs_reserve_extent+0x9b/0x180 [btrfs]
         btrfs_alloc_tree_block+0xc1/0x350 [btrfs]
         alloc_tree_block_no_bg_flush+0x4a/0x60 [btrfs]
         __btrfs_cow_block+0x122/0x5a0 [btrfs]
         btrfs_cow_block+0x106/0x240 [btrfs]
         btrfs_search_slot+0x50c/0xd60 [btrfs]
         btrfs_lookup_inode+0x3a/0xc0 [btrfs]
         __btrfs_update_delayed_inode+0x90/0x280 [btrfs]
         __btrfs_commit_inode_delayed_items+0x81f/0x870 [btrfs]
         __btrfs_run_delayed_items+0x8e/0x180 [btrfs]
         btrfs_commit_transaction+0x31b/0xb20 [btrfs]
         iterate_supers+0x87/0xf0
         ksys_sync+0x60/0xb0
         __ia32_sys_sync+0xa/0x10
         do_syscall_64+0x5c/0x260
         entry_SYSCALL_64_after_hwframe+0x49/0xbe

  -> #0 (&delayed_node->mutex){+.+.}:
         __lock_acquire+0xef0/0x1c80
         lock_acquire+0xa2/0x1d0
         __mutex_lock+0xa9/0xaf0
         __btrfs_release_delayed_node.part.0+0x3f/0x320 [btrfs]
         btrfs_evict_inode+0x40d/0x560 [btrfs]
         evict+0xd9/0x1c0
         dispose_list+0x48/0x70
         prune_icache_sb+0x54/0x80
         super_cache_scan+0x124/0x1a0
         do_shrink_slab+0x176/0x440
         shrink_slab+0x23a/0x2c0
         shrink_node+0x188/0x6e0
         balance_pgdat+0x31d/0x7f0
         kswapd+0x238/0x550
         kthread+0x120/0x140
         ret_from_fork+0x3a/0x50

  other info that might help us debug this:

  Chain exists of:
    &delayed_node->mutex --> pcpu_alloc_mutex --> fs_reclaim

   Possible unsafe locking scenario:

         CPU0                    CPU1
         ----                    ----
    lock(fs_reclaim);
                                 lock(pcpu_alloc_mutex);
                                 lock(fs_reclaim);
    lock(&delayed_node->mutex);

   *** DEADLOCK ***

  3 locks held by kswapd0/91:
   #0: (fs_reclaim){+.+.}, at: __fs_reclaim_acquire+0x5/0x30
   #1: (shrinker_rwsem){++++}, at: shrink_slab+0x12f/0x2c0
   #2: (&type->s_umount_key#43){++++}, at: trylock_super+0x16/0x50

  stack backtrace:
  CPU: 1 PID: 91 Comm: kswapd0 Not tainted 5.6.0-rc7-btrfs-next-77 #1
  Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.12.0-0-ga698c8995f-prebuilt.qemu.org 04/01/2014
  Call Trace:
   dump_stack+0x8f/0xd0
   check_noncircular+0x170/0x190
   __lock_acquire+0xef0/0x1c80
   lock_acquire+0xa2/0x1d0
   __mutex_lock+0xa9/0xaf0
   __btrfs_release_delayed_node.part.0+0x3f/0x320 [btrfs]
   btrfs_evict_inode+0x40d/0x560 [btrfs]
   evict+0xd9/0x1c0
   dispose_list+0x48/0x70
   prune_icache_sb+0x54/0x80
   super_cache_scan+0x124/0x1a0
   do_shrink_slab+0x176/0x440
   shrink_slab+0x23a/0x2c0
   shrink_node+0x188/0x6e0
   balance_pgdat+0x31d/0x7f0
   kswapd+0x238/0x550
   kthread+0x120/0x140
   ret_from_fork+0x3a/0x50

This could be fixed by making btrfs pass GFP_NOFS instead of GFP_KERNEL
to percpu_counter_init() in contextes where it is not reclaim safe,
however that type of approach is discouraged since
memalloc_[nofs|noio]_save() were introduced.  Therefore this change
makes pcpu_alloc() look up into an existing nofs/noio context before
deciding whether it is in an atomic context or not.

Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Tejun Heo <tj@kernel.org>
Acked-by: Dennis Zhou <dennis@kernel.org>
Cc: Tejun Heo <tj@kernel.org>
Cc: Christoph Lameter <cl@linux.com>
Link: http://lkml.kernel.org/r/20200430164356.15543-1-fdmanana@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agomm/slub: fix incorrect interpretation of s->offset
Waiman Long [Fri, 8 May 2020 01:36:06 +0000 (18:36 -0700)]
mm/slub: fix incorrect interpretation of s->offset

In a couple of places in the slub memory allocator, the code uses
"s->offset" as a check to see if the free pointer is put right after the
object.  That check is no longer true with commit 3202fa62fb43 ("slub:
relocate freelist pointer to middle of object").

As a result, echoing "1" into the validate sysfs file, e.g.  of dentry,
may cause a bunch of "Freepointer corrupt" error reports like the
following to appear with the system in panic afterwards.

  =============================================================================
  BUG dentry(666:pmcd.service) (Tainted: G    B): Freepointer corrupt
  -----------------------------------------------------------------------------

To fix it, use the check "s->offset == s->inuse" in the new helper
function freeptr_outside_object() instead.  Also add another helper
function get_info_end() to return the end of info block (inuse + free
pointer if not overlapping with object).

Fixes: 3202fa62fb43 ("slub: relocate freelist pointer to middle of object")
Signed-off-by: Waiman Long <longman@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: Kees Cook <keescook@chromium.org>
Acked-by: Rafael Aquini <aquini@redhat.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Vitaly Nikolenko <vnik@duasynt.com>
Cc: Silvio Cesare <silvio.cesare@gmail.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Markus Elfring <Markus.Elfring@web.de>
Cc: Changbin Du <changbin.du@gmail.com>
Link: http://lkml.kernel.org/r/20200429135328.26976-1-longman@redhat.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agoscripts/gdb: repair rb_first() and rb_last()
Aymeric Agon-Rambosson [Fri, 8 May 2020 01:36:03 +0000 (18:36 -0700)]
scripts/gdb: repair rb_first() and rb_last()

The current implementations of the rb_first() and rb_last() gdb
functions have a variable that references itself in its instanciation,
which causes the function to throw an error if a specific condition on
the argument is met.  The original author rather intended to reference
the argument and made a typo.  Referring the argument instead makes the
function work as intended.

Signed-off-by: Aymeric Agon-Rambosson <aymeric.agon@yandex.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Stephen Boyd <swboyd@chromium.org>
Cc: Jan Kiszka <jan.kiszka@siemens.com>
Cc: Kieran Bingham <kbingham@kernel.org>
Cc: Douglas Anderson <dianders@chromium.org>
Cc: Nikolay Borisov <n.borisov.lkml@gmail.com>
Cc: Jackie Liu <liuyun01@kylinos.cn>
Cc: Jason Wessel <jason.wessel@windriver.com>
Link: http://lkml.kernel.org/r/20200427051029.354840-1-aymeric.agon@yandex.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agoeventpoll: fix missing wakeup for ovflist in ep_poll_callback
Khazhismel Kumykov [Fri, 8 May 2020 01:35:59 +0000 (18:35 -0700)]
eventpoll: fix missing wakeup for ovflist in ep_poll_callback

In the event that we add to ovflist, before commit 339ddb53d373
("fs/epoll: remove unnecessary wakeups of nested epoll") we would be
woken up by ep_scan_ready_list, and did no wakeup in ep_poll_callback.

With that wakeup removed, if we add to ovflist here, we may never wake
up.  Rather than adding back the ep_scan_ready_list wakeup - which was
resulting in unnecessary wakeups, trigger a wake-up in ep_poll_callback.

We noticed that one of our workloads was missing wakeups starting with
339ddb53d373 and upon manual inspection, this wakeup seemed missing to me.
With this patch added, we no longer see missing wakeups.  I haven't yet
tried to make a small reproducer, but the existing kselftests in
filesystem/epoll passed for me with this patch.

[khazhy@google.com: use if/elif instead of goto + cleanup suggested by Roman]
Link: http://lkml.kernel.org/r/20200424190039.192373-1-khazhy@google.com
Fixes: 339ddb53d373 ("fs/epoll: remove unnecessary wakeups of nested epoll")
Signed-off-by: Khazhismel Kumykov <khazhy@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Roman Penyaev <rpenyaev@suse.de>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Roman Penyaev <rpenyaev@suse.de>
Cc: Heiher <r@hev.cc>
Cc: Jason Baron <jbaron@akamai.com>
Cc: <stable@vger.kernel.org>
Link: http://lkml.kernel.org/r/20200424025057.118641-1-khazhy@google.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agoarch/x86/kvm/svm/sev.c: change flag passed to GUP fast in sev_pin_memory()
Janakarajan Natarajan [Fri, 8 May 2020 01:35:56 +0000 (18:35 -0700)]
arch/x86/kvm/svm/sev.c: change flag passed to GUP fast in sev_pin_memory()

When trying to lock read-only pages, sev_pin_memory() fails because
FOLL_WRITE is used as the flag for get_user_pages_fast().

Commit 73b0140bf0fe ("mm/gup: change GUP fast to use flags rather than a
write 'bool'") updated the get_user_pages_fast() call sites to use
flags, but incorrectly updated the call in sev_pin_memory().  As the
original coding of this call was correct, revert the change made by that
commit.

Fixes: 73b0140bf0fe ("mm/gup: change GUP fast to use flags rather than a write 'bool'")
Signed-off-by: Janakarajan Natarajan <Janakarajan.Natarajan@amd.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Ira Weiny <ira.weiny@intel.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Sean Christopherson <sean.j.christopherson@intel.com>
Cc: Vitaly Kuznetsov <vkuznets@redhat.com>
Cc: Wanpeng Li <wanpengli@tencent.com>
Cc: Jim Mattson <jmattson@google.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: "H . Peter Anvin" <hpa@zytor.com>
Cc: Mike Marshall <hubcap@omnibond.com>
Cc: Brijesh Singh <brijesh.singh@amd.com>
Link: http://lkml.kernel.org/r/20200423152419.87202-1-Janakarajan.Natarajan@amd.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agoscripts/decodecode: fix trapping instruction formatting
Ivan Delalande [Fri, 8 May 2020 01:35:53 +0000 (18:35 -0700)]
scripts/decodecode: fix trapping instruction formatting

If the trapping instruction contains a ':', for a memory access through
segment registers for example, the sed substitution will insert the '*'
marker in the middle of the instruction instead of the line address:

2b:   65 48 0f c7 0f          cmpxchg16b %gs:*(%rdi)          <-- trapping instruction

I started to think I had forgotten some quirk of the assembly syntax
before noticing that it was actually coming from the script.  Fix it to
add the address marker at the right place for these instructions:

28:   49 8b 06                mov    (%r14),%rax
2b:*  65 48 0f c7 0f          cmpxchg16b %gs:(%rdi)           <-- trapping instruction
30:   0f 94 c0                sete   %al

Fixes: 18ff44b189e2 ("scripts/decodecode: make faulting insn ptr more robust")
Signed-off-by: Ivan Delalande <colona@arista.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Borislav Petkov <bp@suse.de>
Link: http://lkml.kernel.org/r/20200419223653.GA31248@visor
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agokernel/kcov.c: fix typos in kcov_remote_start documentation
Maciej Grochowski [Fri, 8 May 2020 01:35:49 +0000 (18:35 -0700)]
kernel/kcov.c: fix typos in kcov_remote_start documentation

Signed-off-by: Maciej Grochowski <maciej.grochowski@pm.me>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Andrey Konovalov <andreyknvl@google.com>
Link: http://lkml.kernel.org/r/20200420030259.31674-1-maciek.grochowski@gmail.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agomm/page_alloc: fix watchdog soft lockups during set_zone_contiguous()
David Hildenbrand [Fri, 8 May 2020 01:35:46 +0000 (18:35 -0700)]
mm/page_alloc: fix watchdog soft lockups during set_zone_contiguous()

Without CONFIG_PREEMPT, it can happen that we get soft lockups detected,
e.g., while booting up.

  watchdog: BUG: soft lockup - CPU#0 stuck for 22s! [swapper/0:1]
  CPU: 0 PID: 1 Comm: swapper/0 Not tainted 5.6.0-next-20200331+ #4
  Hardware name: Red Hat KVM, BIOS 1.11.1-4.module+el8.1.0+4066+0f1aadab 04/01/2014
  RIP: __pageblock_pfn_to_page+0x134/0x1c0
  Call Trace:
   set_zone_contiguous+0x56/0x70
   page_alloc_init_late+0x166/0x176
   kernel_init_freeable+0xfa/0x255
   kernel_init+0xa/0x106
   ret_from_fork+0x35/0x40

The issue becomes visible when having a lot of memory (e.g., 4TB)
assigned to a single NUMA node - a system that can easily be created
using QEMU.  Inside VMs on a hypervisor with quite some memory
overcommit, this is fairly easy to trigger.

Signed-off-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Pavel Tatashin <pasha.tatashin@soleen.com>
Reviewed-by: Pankaj Gupta <pankaj.gupta.linux@gmail.com>
Reviewed-by: Baoquan He <bhe@redhat.com>
Reviewed-by: Shile Zhang <shile.zhang@linux.alibaba.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Kirill Tkhai <ktkhai@virtuozzo.com>
Cc: Shile Zhang <shile.zhang@linux.alibaba.com>
Cc: Pavel Tatashin <pasha.tatashin@soleen.com>
Cc: Daniel Jordan <daniel.m.jordan@oracle.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Alexander Duyck <alexander.duyck@gmail.com>
Cc: Baoquan He <bhe@redhat.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: <stable@vger.kernel.org>
Link: http://lkml.kernel.org/r/20200416073417.5003-1-david@redhat.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agomm, memcg: fix error return value of mem_cgroup_css_alloc()
Yafang Shao [Fri, 8 May 2020 01:35:43 +0000 (18:35 -0700)]
mm, memcg: fix error return value of mem_cgroup_css_alloc()

When I run my memcg testcase which creates lots of memcgs, I found
there're unexpected out of memory logs while there're still enough
available free memory.  The error log is

  mkdir: cannot create directory 'foo.65533': Cannot allocate memory

The reason is when we try to create more than MEM_CGROUP_ID_MAX memcgs,
an -ENOMEM errno will be set by mem_cgroup_css_alloc(), but the right
errno should be -ENOSPC "No space left on device", which is an
appropriate errno for userspace's failed mkdir.

As the errno really misled me, we should make it right.  After this
patch, the error log will be

  mkdir: cannot create directory 'foo.65533': No space left on device

[akpm@linux-foundation.org: s/EBUSY/ENOSPC/, per Michal]
[akpm@linux-foundation.org: s/EBUSY/ENOSPC/, per Michal]
Fixes: 73f576c04b94 ("mm: memcontrol: fix cgroup creation failure after many small jobs")
Suggested-by: Matthew Wilcox <willy@infradead.org>
Signed-off-by: Yafang Shao <laoar.shao@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Michal Hocko <mhocko@kernel.org>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Vladimir Davydov <vdavydov.dev@gmail.com>
Link: http://lkml.kernel.org/r/20200407063621.GA18914@dhcp22.suse.cz
Link: http://lkml.kernel.org/r/1586192163-20099-1-git-send-email-laoar.shao@gmail.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agoipc/mqueue.c: change __do_notify() to bypass check_kill_permission()
Oleg Nesterov [Fri, 8 May 2020 01:35:39 +0000 (18:35 -0700)]
ipc/mqueue.c: change __do_notify() to bypass check_kill_permission()

Commit cc731525f26a ("signal: Remove kernel interal si_code magic")
changed the value of SI_FROMUSER(SI_MESGQ), this means that mq_notify() no
longer works if the sender doesn't have rights to send a signal.

Change __do_notify() to use do_send_sig_info() instead of kill_pid_info()
to avoid check_kill_permission().

This needs the additional notify.sigev_signo != 0 check, shouldn't we
change do_mq_notify() to deny sigev_signo == 0 ?

Test-case:

#include <signal.h>
#include <mqueue.h>
#include <unistd.h>
#include <sys/wait.h>
#include <assert.h>

static int notified;

static void sigh(int sig)
{
notified = 1;
}

int main(void)
{
signal(SIGIO, sigh);

int fd = mq_open("/mq", O_RDWR|O_CREAT, 0666, NULL);
assert(fd >= 0);

struct sigevent se = {
.sigev_notify = SIGEV_SIGNAL,
.sigev_signo = SIGIO,
};
assert(mq_notify(fd, &se) == 0);

if (!fork()) {
assert(setuid(1) == 0);
mq_send(fd, "",1,0);
return 0;
}

wait(NULL);
mq_unlink("/mq");
assert(notified);
return 0;
}

[manfred@colorfullife.com: 1) Add self_exec_id evaluation so that the implementation matches do_notify_parent 2) use PIDTYPE_TGID everywhere]
Fixes: cc731525f26a ("signal: Remove kernel interal si_code magic")
Reported-by: Yoji <yoji.fujihar.min@gmail.com>
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Manfred Spraul <manfred@colorfullife.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: Markus Elfring <elfring@users.sourceforge.net>
Cc: <1vier1@web.de>
Cc: <stable@vger.kernel.org>
Link: http://lkml.kernel.org/r/e2a782e4-eab9-4f5c-c749-c07a8f7a4e66@colorfullife.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agoMerge tag 'trace-v5.7-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt...
Linus Torvalds [Thu, 7 May 2020 22:27:11 +0000 (15:27 -0700)]
Merge tag 'trace-v5.7-rc3' of git://git./linux/kernel/git/rostedt/linux-trace

Pull tracing fixes from Steven Rostedt:

 - Fix bootconfig causing kernels to fail with CONFIG_BLK_DEV_RAM
   enabled

 - Fix allocation leaks in bootconfig tool

 - Fix a double initialization of a variable

 - Fix API bootconfig usage from kprobe boot time events

 - Reject NULL location for kprobes

 - Fix crash caused by preempt delay module not cleaning up kthread
   correctly

 - Add vmalloc_sync_mappings() to prevent x86_64 page faults from
   recursively faulting from tracing page faults

 - Fix comment in gpu/trace kerneldoc header

 - Fix documentation of how to create a trace event class

 - Make the local tracing_snapshot_instance_cond() function static

* tag 'trace-v5.7-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  tools/bootconfig: Fix resource leak in apply_xbc()
  tracing: Make tracing_snapshot_instance_cond() static
  tracing: Fix doc mistakes in trace sample
  gpu/trace: Minor comment updates for gpu_mem_total tracepoint
  tracing: Add a vmalloc_sync_mappings() for safe measure
  tracing: Wait for preempt irq delay thread to finish
  tracing/kprobes: Reject new event if loc is NULL
  tracing/boottime: Fix kprobe event API usage
  tracing/kprobes: Fix a double initialization typo
  bootconfig: Fix to remove bootconfig data from initrd while boot

4 years agoMerge tag 'linux-kselftest-5.7-rc5' of git://git.kernel.org/pub/scm/linux/kernel...
Linus Torvalds [Thu, 7 May 2020 22:22:08 +0000 (15:22 -0700)]
Merge tag 'linux-kselftest-5.7-rc5' of git://git./linux/kernel/git/shuah/linux-kselftest

Pull kselftest fixes from Shuah Khan:
 "ftrace test fixes and a fix to kvm Makefile for relocatable
  native/cross builds and installs"

* tag 'linux-kselftest-5.7-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest:
  selftests: fix kvm relocatable native/cross builds and installs
  selftests/ftrace: Make XFAIL green color
  ftrace/selftest: make unresolved cases cause failure if --fail-unresolved set
  ftrace/selftests: workaround cgroup RT scheduling issues

4 years agoio_uring: don't use 'fd' for openat/openat2/statx
Jens Axboe [Thu, 7 May 2020 20:56:15 +0000 (14:56 -0600)]
io_uring: don't use 'fd' for openat/openat2/statx

We currently make some guesses as when to open this fd, but in reality
we have no business (or need) to do so at all. In fact, it makes certain
things fail, like O_PATH.

Remove the fd lookup from these opcodes, we're just passing the 'fd' to
generic helpers anyway. With that, we can also remove the special casing
of fd values in io_req_needs_file(), and the 'fd_non_neg' check that
we have. And we can ensure that we only read sqe->fd once.

This fixes O_PATH usage with openat/openat2, and ditto statx path side
oddities.

Cc: stable@vger.kernel.org: # v5.6
Reported-by: Max Kellermann <mk@cm4all.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
4 years agotools/bootconfig: Fix resource leak in apply_xbc()
Yunfeng Ye [Thu, 7 May 2020 09:23:36 +0000 (17:23 +0800)]
tools/bootconfig: Fix resource leak in apply_xbc()

Fix the @data and @fd allocations that are leaked in the error path of
apply_xbc().

Link: http://lkml.kernel.org/r/583a49c9-c27a-931d-e6c2-6f63a4b18bea@huawei.com
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Yunfeng Ye <yeyunfeng@huawei.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
4 years agotracing: Make tracing_snapshot_instance_cond() static
Zou Wei [Thu, 23 Apr 2020 04:08:25 +0000 (12:08 +0800)]
tracing: Make tracing_snapshot_instance_cond() static

Fix the following sparse warning:

kernel/trace/trace.c:950:6: warning: symbol 'tracing_snapshot_instance_cond'
was not declared. Should it be static?

Link: http://lkml.kernel.org/r/1587614905-48692-1-git-send-email-zou_wei@huawei.com
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Zou Wei <zou_wei@huawei.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
4 years agotracing: Fix doc mistakes in trace sample
Wei Yang [Tue, 28 Apr 2020 21:49:59 +0000 (21:49 +0000)]
tracing: Fix doc mistakes in trace sample

As the example below shows, DECLARE_EVENT_CLASS() is used instead of
DEFINE_EVENT_CLASS().

Link: http://lkml.kernel.org/r/20200428214959.11259-1-richard.weiyang@gmail.com
Signed-off-by: Wei Yang <richard.weiyang@gmail.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
4 years agogpu/trace: Minor comment updates for gpu_mem_total tracepoint
Yiwei Zhang [Tue, 28 Apr 2020 22:08:25 +0000 (15:08 -0700)]
gpu/trace: Minor comment updates for gpu_mem_total tracepoint

This change updates the improper comment for the 'size' attribute in the
tracepoint definition. Most gfx drivers pre-fault in physical pages
instead of making virtual allocations. So we drop the 'Virtual' keyword
here and leave this to the implementations.

Link: http://lkml.kernel.org/r/20200428220825.169606-1-zzyiwei@google.com
Signed-off-by: Yiwei Zhang <zzyiwei@google.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
4 years agotracing: Add a vmalloc_sync_mappings() for safe measure
Steven Rostedt (VMware) [Wed, 6 May 2020 14:36:18 +0000 (10:36 -0400)]
tracing: Add a vmalloc_sync_mappings() for safe measure

x86_64 lazily maps in the vmalloc pages, and the way this works with per_cpu
areas can be complex, to say the least. Mappings may happen at boot up, and
if nothing synchronizes the page tables, those page mappings may not be
synced till they are used. This causes issues for anything that might touch
one of those mappings in the path of the page fault handler. When one of
those unmapped mappings is touched in the page fault handler, it will cause
another page fault, which in turn will cause a page fault, and leave us in
a loop of page faults.

Commit 763802b53a42 ("x86/mm: split vmalloc_sync_all()") split
vmalloc_sync_all() into vmalloc_sync_unmappings() and
vmalloc_sync_mappings(), as on system exit, it did not need to do a full
sync on x86_64 (although it still needed to be done on x86_32). By chance,
the vmalloc_sync_all() would synchronize the page mappings done at boot up
and prevent the per cpu area from being a problem for tracing in the page
fault handler. But when that synchronization in the exit of a task became a
nop, it caused the problem to appear.

Link: https://lore.kernel.org/r/20200429054857.66e8e333@oasis.local.home
Cc: stable@vger.kernel.org
Fixes: 737223fbca3b1 ("tracing: Consolidate buffer allocation code")
Reported-by: "Tzvetomir Stoyanov (VMware)" <tz.stoyanov@gmail.com>
Suggested-by: Joerg Roedel <jroedel@suse.de>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
4 years agotracing: Wait for preempt irq delay thread to finish
Steven Rostedt (VMware) [Wed, 6 May 2020 14:20:10 +0000 (10:20 -0400)]
tracing: Wait for preempt irq delay thread to finish

Running on a slower machine, it is possible that the preempt delay kernel
thread may still be executing if the module was immediately removed after
added, and this can cause the kernel to crash as the kernel thread might be
executing after its code has been removed.

There's no reason that the caller of the code shouldn't just wait for the
delay thread to finish, as the thread can also be created by a trigger in
the sysfs code, which also has the same issues.

Link: http://lore.kernel.org/r/5EA2B0C8.2080706@cn.fujitsu.com
Cc: stable@vger.kernel.org
Fixes: 793937236d1ee ("lib: Add module for testing preemptoff/irqsoff latency tracers")
Reported-by: Xiao Yang <yangx.jy@cn.fujitsu.com>
Reviewed-by: Xiao Yang <yangx.jy@cn.fujitsu.com>
Reviewed-by: Joel Fernandes <joel@joelfernandes.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
4 years agoMerge tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux
Linus Torvalds [Thu, 7 May 2020 16:55:58 +0000 (09:55 -0700)]
Merge tag 'arm64-fixes' of git://git./linux/kernel/git/arm64/linux

Pull arm64 fix from Catalin Marinas:
 "Avoid potential NULL dereference in huge_pte_alloc() on pmd_alloc()
  failure"

* tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux:
  arm64: hugetlb: avoid potential NULL dereference

4 years agoMerge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm
Linus Torvalds [Thu, 7 May 2020 16:50:59 +0000 (09:50 -0700)]
Merge tag 'for-linus' of git://git./virt/kvm/kvm

Pull kvm fixes from Paolo Bonzini:
 "Bugfixes, mostly for ARM and AMD, and more documentation.

  Slightly bigger than usual because I couldn't send out what was
  pending for rc4, but there is nothing worrisome going on. I have more
  fixes pending for guest debugging support (gdbstub) but I will send
  them next week"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (22 commits)
  KVM: X86: Declare KVM_CAP_SET_GUEST_DEBUG properly
  KVM: selftests: Fix build for evmcs.h
  kvm: x86: Use KVM CPU capabilities to determine CR4 reserved bits
  KVM: VMX: Explicitly clear RFLAGS.CF and RFLAGS.ZF in VM-Exit RSB path
  docs/virt/kvm: Document configuring and running nested guests
  KVM: s390: Remove false WARN_ON_ONCE for the PQAP instruction
  kvm: ioapic: Restrict lazy EOI update to edge-triggered interrupts
  KVM: x86: Fixes posted interrupt check for IRQs delivery modes
  KVM: SVM: fill in kvm_run->debug.arch.dr[67]
  KVM: nVMX: Replace a BUG_ON(1) with BUG() to squash clang warning
  KVM: arm64: Fix 32bit PC wrap-around
  KVM: arm64: vgic-v4: Initialize GICv4.1 even in the absence of a virtual ITS
  KVM: arm64: Save/restore sp_el0 as part of __guest_enter
  KVM: arm64: Delete duplicated label in invalid_vector
  KVM: arm64: vgic-its: Fix memory leak on the error path of vgic_add_lpi()
  KVM: arm64: vgic-v3: Retire all pending LPIs on vcpu destroy
  KVM: arm: vgic-v2: Only use the virtual state when userspace accesses pending bits
  KVM: arm: vgic: Only use the virtual state when userspace accesses enable bits
  KVM: arm: vgic: Synchronize the whole guest on GIC{D,R}_I{S,C}ACTIVER read
  KVM: arm64: PSCI: Forbid 64bit functions for 32bit guests
  ...

4 years agoMerge tag 'configfs-for-5.7' of git://git.infradead.org/users/hch/configfs
Linus Torvalds [Thu, 7 May 2020 16:48:37 +0000 (09:48 -0700)]
Merge tag 'configfs-for-5.7' of git://git.infradead.org/users/hch/configfs

Pull configfs fix from Christoph Hellwig:
 "Fix a refcount leak in configfs_rmdir (Xiyu Yang)"

* tag 'configfs-for-5.7' of git://git.infradead.org/users/hch/configfs:
  configfs: fix config_item refcnt leak in configfs_rmdir()

4 years agosplice: move f_mode checks to do_{splice,tee}()
Pavel Begunkov [Mon, 4 May 2020 19:39:35 +0000 (22:39 +0300)]
splice: move f_mode checks to do_{splice,tee}()

do_splice() is used by io_uring, as will be do_tee(). Move f_mode
checks from sys_{splice,tee}() to do_{splice,tee}(), so they're
enforced for io_uring as well.

Fixes: 7d67af2c0134 ("io_uring: add splice(2) support")
Reported-by: Jann Horn <jannh@google.com>
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
4 years agoarm64: hugetlb: avoid potential NULL dereference
Mark Rutland [Tue, 5 May 2020 12:59:30 +0000 (13:59 +0100)]
arm64: hugetlb: avoid potential NULL dereference

The static analyzer in GCC 10 spotted that in huge_pte_alloc() we may
pass a NULL pmdp into pte_alloc_map() when pmd_alloc() returns NULL:

|   CC      arch/arm64/mm/pageattr.o
|   CC      arch/arm64/mm/hugetlbpage.o
|                  from arch/arm64/mm/hugetlbpage.c:10:
| arch/arm64/mm/hugetlbpage.c: In function ‘huge_pte_alloc’:
| ./arch/arm64/include/asm/pgtable-types.h:28:24: warning: dereference of NULL ‘pmdp’ [CWE-690] [-Wanalyzer-null-dereference]
| ./arch/arm64/include/asm/pgtable.h:436:26: note: in expansion of macro ‘pmd_val’
| arch/arm64/mm/hugetlbpage.c:242:10: note: in expansion of macro ‘pte_alloc_map’
|     |arch/arm64/mm/hugetlbpage.c:232:10:
|     |./arch/arm64/include/asm/pgtable-types.h:28:24:
| ./arch/arm64/include/asm/pgtable.h:436:26: note: in expansion of macro ‘pmd_val’
| arch/arm64/mm/hugetlbpage.c:242:10: note: in expansion of macro ‘pte_alloc_map’

This can only occur when the kernel cannot allocate a page, and so is
unlikely to happen in practice before other systems start failing.

We can avoid this by bailing out if pmd_alloc() fails, as we do earlier
in the function if pud_alloc() fails.

Fixes: 66b3923a1a0f ("arm64: hugetlb: add support for PTE contiguous bit")
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Reported-by: Kyrill Tkachov <kyrylo.tkachov@arm.com>
Cc: <stable@vger.kernel.org> # 4.5.x-
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
4 years agousb: chipidea: msm: Ensure proper controller reset using role switch API
Bryan O'Donoghue [Thu, 7 May 2020 00:49:18 +0000 (08:49 +0800)]
usb: chipidea: msm: Ensure proper controller reset using role switch API

Currently we check to make sure there is no error state on the extcon
handle for VBUS when writing to the HS_PHY_GENCONFIG_2 register. When using
the USB role-switch API we still need to write to this register absent an
extcon handle.

This patch makes the appropriate update to ensure the write happens if
role-switching is true.

Fixes: 05559f10ed79 ("usb: chipidea: add role switch class support")
Cc: stable <stable@vger.kernel.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Philipp Zabel <p.zabel@pengutronix.de>
Cc: linux-usb@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Cc: Stephen Boyd <swboyd@chromium.org>
Signed-off-by: Bryan O'Donoghue <bryan.odonoghue@linaro.org>
Signed-off-by: Peter Chen <peter.chen@nxp.com>
Link: https://lore.kernel.org/r/20200507004918.25975-2-peter.chen@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
4 years agoMerge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Linus Torvalds [Thu, 7 May 2020 03:53:22 +0000 (20:53 -0700)]
Merge git://git./linux/kernel/git/netdev/net

Pull networking fixes from David Miller:

 1) Fix reference count leaks in various parts of batman-adv, from Xiyu
    Yang.

 2) Update NAT checksum even when it is zero, from Guillaume Nault.

 3) sk_psock reference count leak in tls code, also from Xiyu Yang.

 4) Sanity check TCA_FQ_CODEL_DROP_BATCH_SIZE netlink attribute in
    fq_codel, from Eric Dumazet.

 5) Fix panic in choke_reset(), also from Eric Dumazet.

 6) Fix VLAN accel handling in bnxt_fix_features(), from Michael Chan.

 7) Disallow out of range quantum values in sch_sfq, from Eric Dumazet.

 8) Fix crash in x25_disconnect(), from Yue Haibing.

 9) Don't pass pointer to local variable back to the caller in
    nf_osf_hdr_ctx_init(), from Arnd Bergmann.

10) Wireguard should use the ECN decap helper functions, from Toke
    Høiland-Jørgensen.

11) Fix command entry leak in mlx5 driver, from Moshe Shemesh.

12) Fix uninitialized variable access in mptcp's
    subflow_syn_recv_sock(), from Paolo Abeni.

13) Fix unnecessary out-of-order ingress frame ordering in macsec, from
    Scott Dial.

14) IPv6 needs to use a global serial number for dst validation just
    like ipv4, from David Ahern.

15) Fix up PTP_1588_CLOCK deps, from Clay McClure.

16) Missing NLM_F_MULTI flag in gtp driver netlink messages, from
    Yoshiyuki Kurauchi.

17) Fix a regression in that dsa user port errors should not be fatal,
    from Florian Fainelli.

18) Fix iomap leak in enetc driver, from Dejin Zheng.

19) Fix use after free in lec_arp_clear_vccs(), from Cong Wang.

20) Initialize protocol value earlier in neigh code paths when
    generating events, from Roman Mashak.

21) netdev_update_features() must be called with RTNL mutex in macsec
    driver, from Antoine Tenart.

22) Validate untrusted GSO packets even more strictly, from Willem de
    Bruijn.

23) Wireguard decrypt worker needs a cond_resched(), from Jason
    Donenfeld.

* git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (111 commits)
  net: flow_offload: skip hw stats check for FLOW_ACTION_HW_STATS_DONT_CARE
  MAINTAINERS: put DYNAMIC INTERRUPT MODERATION in proper order
  wireguard: send/receive: use explicit unlikely branch instead of implicit coalescing
  wireguard: selftests: initalize ipv6 members to NULL to squelch clang warning
  wireguard: send/receive: cond_resched() when processing worker ringbuffers
  wireguard: socket: remove errant restriction on looping to self
  wireguard: selftests: use normal kernel stack size on ppc64
  net: ethernet: ti: am65-cpsw-nuss: fix irqs type
  ionic: Use debugfs_create_bool() to export bool
  net: dsa: Do not leave DSA master with NULL netdev_ops
  net: dsa: remove duplicate assignment in dsa_slave_add_cls_matchall_mirred
  net: stricter validation of untrusted gso packets
  seg6: fix SRH processing to comply with RFC8754
  net: mscc: ocelot: ANA_AUTOAGE_AGE_PERIOD holds a value in seconds, not ms
  net: dsa: ocelot: the MAC table on Felix is twice as large
  net: dsa: sja1105: the PTP_CLK extts input reacts on both edges
  selftests: net: tcp_mmap: fix SO_RCVLOWAT setting
  net: hsr: fix incorrect type usage for protocol variable
  net: macsec: fix rtnl locking issue
  net: mvpp2: cls: Prevent buffer overflow in mvpp2_ethtool_cls_rule_del()
  ...

4 years agonet: flow_offload: skip hw stats check for FLOW_ACTION_HW_STATS_DONT_CARE
Pablo Neira Ayuso [Wed, 6 May 2020 18:34:50 +0000 (20:34 +0200)]
net: flow_offload: skip hw stats check for FLOW_ACTION_HW_STATS_DONT_CARE

This patch adds FLOW_ACTION_HW_STATS_DONT_CARE which tells the driver
that the frontend does not need counters, this hw stats type request
never fails. The FLOW_ACTION_HW_STATS_DISABLED type explicitly requests
the driver to disable the stats, however, if the driver cannot disable
counters, it bails out.

TCA_ACT_HW_STATS_* maintains the 1:1 mapping with FLOW_ACTION_HW_STATS_*
except by disabled which is mapped to FLOW_ACTION_HW_STATS_DISABLED
(this is 0 in tc). Add tc_act_hw_stats() to perform the mapping between
TCA_ACT_HW_STATS_* and FLOW_ACTION_HW_STATS_*.

Fixes: 319a1d19471e ("flow_offload: check for basic action hw stats type")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
4 years agoMAINTAINERS: put DYNAMIC INTERRUPT MODERATION in proper order
Lukas Bulwahn [Wed, 6 May 2020 20:29:06 +0000 (22:29 +0200)]
MAINTAINERS: put DYNAMIC INTERRUPT MODERATION in proper order

Commit 9b038086f06b ("docs: networking: convert DIM to RST") added a new
file entry to DYNAMIC INTERRUPT MODERATION to the end, and not following
alphabetical order.

So, ./scripts/checkpatch.pl -f MAINTAINERS complains:

  WARNING: Misordered MAINTAINERS entry - list file patterns in alphabetic
  order
  #5966: FILE: MAINTAINERS:5966:
  +F:      lib/dim/
  +F:      Documentation/networking/net_dim.rst

Reorder the file entries to keep MAINTAINERS nicely ordered.

Signed-off-by: Lukas Bulwahn <lukas.bulwahn@gmail.com>
Acked-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
4 years agoMerge branch 'wireguard-fixes'
David S. Miller [Thu, 7 May 2020 03:03:48 +0000 (20:03 -0700)]
Merge branch 'wireguard-fixes'

Jason A. Donenfeld says:

====================
wireguard fixes for 5.7-rc5

With Ubuntu and Debian having backported this into their kernels, we're
finally seeing testing from places we hadn't seen prior, which is nice.
With that comes more fixes:

1) The CI for PPC64 was running with extremely small stacks for 64-bit,
   causing spurious crashes in surprising places.

2) There's was an old leftover routing loop restriction, which no longer
   makes sense given the queueing architecture, and was causing problems
   for people who really did want nested routing.

3) Not yielding our kthread on CONFIG_PREEMPT_VOLUNTARY systems caused
   RCU stalls and other issues, reported by Wang Jian, with the fix
   suggested by Sultan Alsawaf.

4) Clang spewed warnings in a selftest for CONFIG_IPV6=n, reported by
   Arnd Bergmann.

5) A complicated if statement was simplified to an assignment while also
   making the likely/unlikely hinting more correct and simple, and
   increasing readability, suggested by Sultan.

Patches (2) and (3) have Fixes: lines and are probably good candidates
for stable.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
4 years agowireguard: send/receive: use explicit unlikely branch instead of implicit coalescing
Jason A. Donenfeld [Wed, 6 May 2020 21:33:06 +0000 (15:33 -0600)]
wireguard: send/receive: use explicit unlikely branch instead of implicit coalescing

It's very unlikely that send will become true. It's nearly always false
between 0 and 120 seconds of a session, and in most cases becomes true
only between 120 and 121 seconds before becoming false again. So,
unlikely(send) is clearly the right option here.

What happened before was that we had this complex boolean expression
with multiple likely and unlikely clauses nested. Since this is
evaluated left-to-right anyway, the whole thing got converted to
unlikely. So, we can clean this up to better represent what's going on.

The generated code is the same.

Suggested-by: Sultan Alsawaf <sultan@kerneltoast.com>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
4 years agowireguard: selftests: initalize ipv6 members to NULL to squelch clang warning
Jason A. Donenfeld [Wed, 6 May 2020 21:33:05 +0000 (15:33 -0600)]
wireguard: selftests: initalize ipv6 members to NULL to squelch clang warning

Without setting these to NULL, clang complains in certain
configurations that have CONFIG_IPV6=n:

In file included from drivers/net/wireguard/ratelimiter.c:223:
drivers/net/wireguard/selftest/ratelimiter.c:173:34: error: variable 'skb6' is uninitialized when used here [-Werror,-Wuninitialized]
                ret = timings_test(skb4, hdr4, skb6, hdr6, &test_count);
                                               ^~~~
drivers/net/wireguard/selftest/ratelimiter.c:123:29: note: initialize the variable 'skb6' to silence this warning
        struct sk_buff *skb4, *skb6;
                                   ^
                                    = NULL
drivers/net/wireguard/selftest/ratelimiter.c:173:40: error: variable 'hdr6' is uninitialized when used here [-Werror,-Wuninitialized]
                ret = timings_test(skb4, hdr4, skb6, hdr6, &test_count);
                                                     ^~~~
drivers/net/wireguard/selftest/ratelimiter.c:125:22: note: initialize the variable 'hdr6' to silence this warning
        struct ipv6hdr *hdr6;
                            ^

We silence this warning by setting the variables to NULL as the warning
suggests.

Reported-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
4 years agowireguard: send/receive: cond_resched() when processing worker ringbuffers
Jason A. Donenfeld [Wed, 6 May 2020 21:33:04 +0000 (15:33 -0600)]
wireguard: send/receive: cond_resched() when processing worker ringbuffers

Users with pathological hardware reported CPU stalls on CONFIG_
PREEMPT_VOLUNTARY=y, because the ringbuffers would stay full, meaning
these workers would never terminate. That turned out not to be okay on
systems without forced preemption, which Sultan observed. This commit
adds a cond_resched() to the bottom of each loop iteration, so that
these workers don't hog the core. Note that we don't need this on the
napi poll worker, since that terminates after its budget is expended.

Suggested-by: Sultan Alsawaf <sultan@kerneltoast.com>
Reported-by: Wang Jian <larkwang@gmail.com>
Fixes: e7096c131e51 ("net: WireGuard secure network tunnel")
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
4 years agowireguard: socket: remove errant restriction on looping to self
Jason A. Donenfeld [Wed, 6 May 2020 21:33:03 +0000 (15:33 -0600)]
wireguard: socket: remove errant restriction on looping to self

It's already possible to create two different interfaces and loop
packets between them. This has always been possible with tunnels in the
kernel, and isn't specific to wireguard. Therefore, the networking stack
already needs to deal with that. At the very least, the packet winds up
exceeding the MTU and is discarded at that point. So, since this is
already something that happens, there's no need to forbid the not very
exceptional case of routing a packet back to the same interface; this
loop is no different than others, and we shouldn't special case it, but
rather rely on generic handling of loops in general. This also makes it
easier to do interesting things with wireguard such as onion routing.

At the same time, we add a selftest for this, ensuring that both onion
routing works and infinite routing loops do not crash the kernel. We
also add a test case for wireguard interfaces nesting packets and
sending traffic between each other, as well as the loop in this case
too. We make sure to send some throughput-heavy traffic for this use
case, to stress out any possible recursion issues with the locks around
workqueues.

Fixes: e7096c131e51 ("net: WireGuard secure network tunnel")
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
4 years agowireguard: selftests: use normal kernel stack size on ppc64
Jason A. Donenfeld [Wed, 6 May 2020 21:33:02 +0000 (15:33 -0600)]
wireguard: selftests: use normal kernel stack size on ppc64

While at some point it might have made sense to be running these tests
on ppc64 with 4k stacks, the kernel hasn't actually used 4k stacks on
64-bit powerpc in a long time, and more interesting things that we test
don't really work when we deviate from the default (16k). So, we stop
pushing our luck in this commit, and return to the default instead of
the minimum.

Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
4 years agonet: ethernet: ti: am65-cpsw-nuss: fix irqs type
Grygorii Strashko [Tue, 5 May 2020 16:31:26 +0000 (19:31 +0300)]
net: ethernet: ti: am65-cpsw-nuss: fix irqs type

The K3 INTA driver, which is source TX/RX IRQs for CPSW NUSS, defines IRQs
triggering type as EDGE by default, but triggering type for CPSW NUSS TX/RX
IRQs has to be LEVEL as the EDGE triggering type may cause unnecessary IRQs
triggering and NAPI scheduling for empty queues. It was discovered with
RT-kernel.

Fix it by explicitly specifying CPSW NUSS TX/RX IRQ type as
IRQF_TRIGGER_HIGH.

Fixes: 93a76530316a ("net: ethernet: ti: introduce am65x/j721e gigabit eth subsystem driver")
Signed-off-by: Grygorii Strashko <grygorii.strashko@ti.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
4 years agoionic: Use debugfs_create_bool() to export bool
Geert Uytterhoeven [Tue, 5 May 2020 13:28:09 +0000 (15:28 +0200)]
ionic: Use debugfs_create_bool() to export bool

Currently bool ionic_cq.done_color is exported using
debugfs_create_u8(), which requires a cast, preventing further compiler
checks.

Fix this by switching to debugfs_create_bool(), and dropping the cast.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Acked-by: Shannon Nelson <snelson@pensando.io>
Signed-off-by: David S. Miller <davem@davemloft.net>
4 years agonet: dsa: Do not leave DSA master with NULL netdev_ops
Florian Fainelli [Mon, 4 May 2020 20:18:06 +0000 (13:18 -0700)]
net: dsa: Do not leave DSA master with NULL netdev_ops

When ndo_get_phys_port_name() for the CPU port was added we introduced
an early check for when the DSA master network device in
dsa_master_ndo_setup() already implements ndo_get_phys_port_name(). When
we perform the teardown operation in dsa_master_ndo_teardown() we would
not be checking that cpu_dp->orig_ndo_ops was successfully allocated and
non-NULL initialized.

With network device drivers such as virtio_net, this leads to a NPD as
soon as the DSA switch hanging off of it gets torn down because we are
now assigning the virtio_net device's netdev_ops a NULL pointer.

Fixes: da7b9e9b00d4 ("net: dsa: Add ndo_get_phys_port_name() for CPU port")
Reported-by: Allen Pais <allen.pais@oracle.com>
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Tested-by: Allen Pais <allen.pais@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
4 years agonet: dsa: remove duplicate assignment in dsa_slave_add_cls_matchall_mirred
Vladimir Oltean [Mon, 4 May 2020 19:58:56 +0000 (22:58 +0300)]
net: dsa: remove duplicate assignment in dsa_slave_add_cls_matchall_mirred

This was caused by a poor merge conflict resolution on my side. The
"act = &cls->rule->action.entries[0];" assignment was already present in
the code prior to the patch mentioned below.

Fixes: e13c2075280e ("net: dsa: refactor matchall mirred action to separate function")
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
4 years agonet: stricter validation of untrusted gso packets
Willem de Bruijn [Mon, 4 May 2020 16:48:54 +0000 (12:48 -0400)]
net: stricter validation of untrusted gso packets

Syzkaller again found a path to a kernel crash through bad gso input:
a packet with transport header extending beyond skb_headlen(skb).

Tighten validation at kernel entry:

- Verify that the transport header lies within the linear section.

    To avoid pulling linux/tcp.h, verify just sizeof tcphdr.
    tcp_gso_segment will call pskb_may_pull (th->doff * 4) before use.

- Match the gso_type against the ip_proto found by the flow dissector.

Fixes: bfd5f4a3d605 ("packet: Add GSO/csum offload support.")
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
4 years agoseg6: fix SRH processing to comply with RFC8754
Ahmed Abdelsalam [Mon, 4 May 2020 14:42:11 +0000 (14:42 +0000)]
seg6: fix SRH processing to comply with RFC8754

The Segment Routing Header (SRH) which defines the SRv6 dataplane is defined
in RFC8754.

RFC8754 (section 4.1) defines the SR source node behavior which encapsulates
packets into an outer IPv6 header and SRH. The SR source node encodes the
full list of Segments that defines the packet path in the SRH. Then, the
first segment from list of Segments is copied into the Destination address
of the outer IPv6 header and the packet is sent to the first hop in its path
towards the destination.

If the Segment list has only one segment, the SR source node can omit the SRH
as he only segment is added in the destination address.

RFC8754 (section 4.1.1) defines the Reduced SRH, when a source does not
require the entire SID list to be preserved in the SRH. A reduced SRH does
not contain the first segment of the related SR Policy (the first segment is
the one already in the DA of the IPv6 header), and the Last Entry field is
set to n-2, where n is the number of elements in the SR Policy.

RFC8754 (section 4.3.1.1) defines the SRH processing and the logic to
validate the SRH (S09, S10, S11) which works for both reduced and
non-reduced behaviors.

This patch updates seg6_validate_srh() to validate the SRH as per RFC8754.

Signed-off-by: Ahmed Abdelsalam <ahabdels@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
4 years agoMerge branch 'FDB-fixes-for-Felix-and-Ocelot-switches'
David S. Miller [Thu, 7 May 2020 00:15:38 +0000 (17:15 -0700)]
Merge branch 'FDB-fixes-for-Felix-and-Ocelot-switches'

Vladimir Oltean says:

====================
FDB fixes for Felix and Ocelot switches

This series fixes the following problems:
- Dynamically learnt addresses never expiring (neither for Ocelot nor
  for Felix)
- Half of the FDB not visible in 'bridge fdb show' (for Felix only)
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
4 years agonet: mscc: ocelot: ANA_AUTOAGE_AGE_PERIOD holds a value in seconds, not ms
Vladimir Oltean [Sun, 3 May 2020 22:20:27 +0000 (01:20 +0300)]
net: mscc: ocelot: ANA_AUTOAGE_AGE_PERIOD holds a value in seconds, not ms

One may notice that automatically-learnt entries 'never' expire, even
though the bridge configures the address age period at 300 seconds.

Actually the value written to hardware corresponds to a time interval
1000 times higher than intended, i.e. 83 hours.

Fixes: a556c76adc05 ("net: mscc: Add initial Ocelot switch support")
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Florian Faineli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
4 years agonet: dsa: ocelot: the MAC table on Felix is twice as large
Vladimir Oltean [Sun, 3 May 2020 22:20:26 +0000 (01:20 +0300)]
net: dsa: ocelot: the MAC table on Felix is twice as large

When running 'bridge fdb dump' on Felix, sometimes learnt and static MAC
addresses would appear, sometimes they wouldn't.

Turns out, the MAC table has 4096 entries on VSC7514 (Ocelot) and 8192
entries on VSC9959 (Felix), so the existing code from the Ocelot common
library only dumped half of Felix's MAC table. They are both organized
as a 4-way set-associative TCAM, so we just need a single variable
indicating the correct number of rows.

Fixes: 56051948773e ("net: dsa: ocelot: add driver for Felix switch family")
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
4 years agoMerge tag 'tag-chrome-platform-fixes-for-v5.7-rc5' of git://git.kernel.org/pub/scm...
Linus Torvalds [Wed, 6 May 2020 23:40:14 +0000 (16:40 -0700)]
Merge tag 'tag-chrome-platform-fixes-for-v5.7-rc5' of git://git./linux/kernel/git/chrome-platform/linux

Pull chrome platform fix from Benson Leung:
 "Fix a resource allocation issue in cros_ec_sensorhub.c"

* tag 'tag-chrome-platform-fixes-for-v5.7-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/chrome-platform/linux:
  platform/chrome: cros_ec_sensorhub: Allocate sensorhub resource before claiming sensors

4 years agonet: dsa: sja1105: the PTP_CLK extts input reacts on both edges
Vladimir Oltean [Wed, 6 May 2020 17:48:13 +0000 (20:48 +0300)]
net: dsa: sja1105: the PTP_CLK extts input reacts on both edges

It looks like the sja1105 external timestamping input is not as generic
as we thought. When fed a signal with 50% duty cycle, it will timestamp
both the rising and the falling edge. When fed a short pulse signal,
only the timestamp of the falling edge will be seen in the PTPSYNCTS
register, because that of the rising edge had been overwritten. So the
moral is: don't feed it short pulse inputs.

Luckily this is not a complete deal breaker, as we can still work with
1 Hz square waves. But the problem is that the extts polling period was
not dimensioned enough for this input signal. If we leave the period at
half a second, we risk losing timestamps due to jitter in the measuring
process. So we need to increase it to 4 times per second.

Also, the very least we can do to inform the user is to deny any other
flags combination than with PTP_RISING_EDGE and PTP_FALLING_EDGE both
set.

Fixes: 747e5eb31d59 ("net: dsa: sja1105: configure the PTP_CLK pin as EXT_TS or PER_OUT")
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Acked-by: Richard Cochran <richardcochran@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
4 years agoselftests: net: tcp_mmap: fix SO_RCVLOWAT setting
Eric Dumazet [Wed, 6 May 2020 16:21:15 +0000 (09:21 -0700)]
selftests: net: tcp_mmap: fix SO_RCVLOWAT setting

Since chunk_size is no longer an integer, we can not
use it directly as an argument of setsockopt().

This patch should fix tcp_mmap for Big Endian kernels.

Fixes: 597b01edafac ("selftests: net: avoid ptl lock contention in tcp_mmap")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Soheil Hassas Yeganeh <soheil@google.com>
Cc: Arjun Roy <arjunroy@google.com>
Acked-by: Soheil Hassas Yeganeh <soheil@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
4 years agonet: hsr: fix incorrect type usage for protocol variable
Murali Karicheri [Wed, 6 May 2020 15:41:07 +0000 (11:41 -0400)]
net: hsr: fix incorrect type usage for protocol variable

Fix following sparse checker warning:-

net/hsr/hsr_slave.c:38:18: warning: incorrect type in assignment (different base types)
net/hsr/hsr_slave.c:38:18:    expected unsigned short [unsigned] [usertype] protocol
net/hsr/hsr_slave.c:38:18:    got restricted __be16 [usertype] h_proto
net/hsr/hsr_slave.c:39:25: warning: restricted __be16 degrades to integer
net/hsr/hsr_slave.c:39:57: warning: restricted __be16 degrades to integer

Signed-off-by: Murali Karicheri <m-karicheri2@ti.com>
Acked-by: Vinicius Costa Gomes <vinicius.gomes@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
4 years agonet: macsec: fix rtnl locking issue
Antoine Tenart [Wed, 6 May 2020 13:58:30 +0000 (15:58 +0200)]
net: macsec: fix rtnl locking issue

netdev_update_features() must be called with the rtnl lock taken. Not
doing so triggers a warning, as ASSERT_RTNL() is used in
__netdev_update_features(), the first function called by
netdev_update_features(). Fix this.

Fixes: c850240b6c41 ("net: macsec: report real_dev features when HW offloading is enabled")
Signed-off-by: Antoine Tenart <antoine.tenart@bootlin.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
4 years agonet: mvpp2: cls: Prevent buffer overflow in mvpp2_ethtool_cls_rule_del()
Dan Carpenter [Wed, 6 May 2020 10:16:56 +0000 (13:16 +0300)]
net: mvpp2: cls: Prevent buffer overflow in mvpp2_ethtool_cls_rule_del()

The "info->fs.location" is a u32 that comes from the user via the
ethtool_set_rxnfc() function.  We need to check for invalid values to
prevent a buffer overflow.

I copy and pasted this check from the mvpp2_ethtool_cls_rule_ins()
function.

Fixes: 90b509b39ac9 ("net: mvpp2: cls: Add Classification offload support")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
4 years agonet: mvpp2: prevent buffer overflow in mvpp22_rss_ctx()
Dan Carpenter [Wed, 6 May 2020 10:16:22 +0000 (13:16 +0300)]
net: mvpp2: prevent buffer overflow in mvpp22_rss_ctx()

The "rss_context" variable comes from the user via  ethtool_get_rxfh().
It can be any u32 value except zero.  Eventually it gets passed to
mvpp22_rss_ctx() and if it is over MVPP22_N_RSS_TABLES (8) then it
results in an array overflow.

Fixes: 895586d5dc32 ("net: mvpp2: cls: Use RSS contexts to handle RSS tables")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
4 years agoselftests: net: tcp_mmap: clear whole tcp_zerocopy_receive struct
Eric Dumazet [Wed, 6 May 2020 03:51:06 +0000 (20:51 -0700)]
selftests: net: tcp_mmap: clear whole tcp_zerocopy_receive struct

We added fields in tcp_zerocopy_receive structure,
so make sure to clear all fields to not pass garbage to the kernel.

We were lucky because recent additions added 'out' parameters,
still we need to clean our reference implementation, before folks
copy/paste it.

Fixes: c8856c051454 ("tcp-zerocopy: Return inq along with tcp receive zerocopy.")
Fixes: 33946518d493 ("tcp-zerocopy: Return sk_err (if set) along with tcp receive zerocopy.")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Arjun Roy <arjunroy@google.com>
Cc: Soheil Hassas Yeganeh <soheil@google.com>
Acked-by: Soheil Hassas Yeganeh <soheil@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
4 years agoMerge branch 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6
Linus Torvalds [Wed, 6 May 2020 17:20:00 +0000 (10:20 -0700)]
Merge branch 'linus' of git://git./linux/kernel/git/herbert/crypto-2.6

Pull crypto fixes from Herbert Xu:
 "This fixes a potential scheduling latency problem for the algorithms
  used by WireGuard"

* 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6:
  crypto: arch/nhpoly1305 - process in explicit 4k chunks
  crypto: arch/lib - limit simd usage to 4k chunks

4 years agoMerge tag 'usb-serial-5.7-rc5' of https://git.kernel.org/pub/scm/linux/kernel/git...
Greg Kroah-Hartman [Wed, 6 May 2020 15:26:35 +0000 (17:26 +0200)]
Merge tag 'usb-serial-5.7-rc5' of https://git./linux/kernel/git/johan/usb-serial into usb-linus

Johan writes:

USB-serial fixes for 5.7-rc5

Here's a fix adding a missing input sanity check and a new modem device
id.

Both have been in linux-next with no reported issues.

* tag 'usb-serial-5.7-rc5' of https://git.kernel.org/pub/scm/linux/kernel/git/johan/usb-serial:
  USB: serial: qcserial: Add DW5816e support
  USB: serial: garmin_gps: add sanity checking for data length

4 years agotracing/kprobes: Reject new event if loc is NULL
Masami Hiramatsu [Sat, 25 Apr 2020 05:49:26 +0000 (14:49 +0900)]
tracing/kprobes: Reject new event if loc is NULL

Reject the new event which has NULL location for kprobes.
For kprobes, user must specify at least the location.

Link: http://lkml.kernel.org/r/158779376597.6082.1411212055469099461.stgit@devnote2
Cc: Tom Zanussi <zanussi@kernel.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: stable@vger.kernel.org
Fixes: 2a588dd1d5d6 ("tracing: Add kprobe event command generation functions")
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
4 years agotracing/boottime: Fix kprobe event API usage
Masami Hiramatsu [Sat, 25 Apr 2020 05:49:17 +0000 (14:49 +0900)]
tracing/boottime: Fix kprobe event API usage

Fix boottime kprobe events to use API correctly for
multiple events.

For example, when we set a multiprobe kprobe events in
bootconfig like below,

  ftrace.event.kprobes.myevent {
   probes = "vfs_read $arg1 $arg2", "vfs_write $arg1 $arg2"
  }

This cause an error;

  trace_boot: Failed to add probe: p:kprobes/myevent (null)  vfs_read $arg1 $arg2  vfs_write $arg1 $arg2

This shows the 1st argument becomes NULL and multiprobes
are merged to 1 probe.

Link: http://lkml.kernel.org/r/158779375766.6082.201939936008972838.stgit@devnote2
Cc: Ingo Molnar <mingo@kernel.org>
Cc: stable@vger.kernel.org
Fixes: 29a154810546 ("tracing: Change trace_boot to use kprobe_event interface")
Reviewed-by: Tom Zanussi <zanussi@kernel.org>
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
4 years agotracing/kprobes: Fix a double initialization typo
Masami Hiramatsu [Sat, 25 Apr 2020 05:49:09 +0000 (14:49 +0900)]
tracing/kprobes: Fix a double initialization typo

Fix a typo that resulted in an unnecessary double
initialization to addr.

Link: http://lkml.kernel.org/r/158779374968.6082.2337484008464939919.stgit@devnote2
Cc: Tom Zanussi <zanussi@kernel.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: stable@vger.kernel.org
Fixes: c7411a1a126f ("tracing/kprobe: Check whether the non-suffixed symbol is notrace")
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
4 years agobootconfig: Fix to remove bootconfig data from initrd while boot
Masami Hiramatsu [Sun, 26 Apr 2020 06:53:30 +0000 (15:53 +0900)]
bootconfig: Fix to remove bootconfig data from initrd while boot

If there is a bootconfig data in the tail of initrd/initramfs,
initrd image sanity check caused an error while decompression
stage as follows.

[    0.883882] Unpacking initramfs...
[    2.696429] Initramfs unpacking failed: invalid magic at start of compressed archive

This error will be ignored if CONFIG_BLK_DEV_RAM=n,
but CONFIG_BLK_DEV_RAM=y the kernel failed to mount rootfs
and causes a panic.

To fix this issue, shrink down the initrd_end for removing
tailing bootconfig data while boot the kernel.

Link: http://lkml.kernel.org/r/158788401014.24243.17424755854115077915.stgit@devnote2
Cc: Borislav Petkov <bp@alien8.de>
Cc: Kees Cook <keescook@chromium.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: stable@vger.kernel.org
Fixes: 7684b8582c24 ("bootconfig: Load boot config from the tail of initrd")
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
4 years agoMerge tag 'kvm-s390-master-5.7-3' of git://git.kernel.org/pub/scm/linux/kernel/git...
Paolo Bonzini [Wed, 6 May 2020 12:09:17 +0000 (08:09 -0400)]
Merge tag 'kvm-s390-master-5.7-3' of git://git./linux/kernel/git/kvms390/linux into HEAD

KVM: s390: Fix for running nested uner z/VM

There are circumstances when running nested under z/VM that would trigger a
WARN_ON_ONCE. Remove the WARN_ON_ONCE. Long term we certainly want to make this
code more robust and flexible, but just returning instead of WARNING makes
guest bootable again.

4 years agoKVM: X86: Declare KVM_CAP_SET_GUEST_DEBUG properly
Peter Xu [Tue, 5 May 2020 15:47:50 +0000 (11:47 -0400)]
KVM: X86: Declare KVM_CAP_SET_GUEST_DEBUG properly

KVM_CAP_SET_GUEST_DEBUG should be supported for x86 however it's not declared
as supported.  My wild guess is that userspaces like QEMU are using "#ifdef
KVM_CAP_SET_GUEST_DEBUG" to check for the capability instead, but that could be
wrong because the compilation host may not be the runtime host.

The userspace might still want to keep the old "#ifdef" though to not break the
guest debug on old kernels.

Signed-off-by: Peter Xu <peterx@redhat.com>
Message-Id: <20200505154750.126300-1-peterx@redhat.com>
[Do the same for PPC and s390. - Paolo]
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
4 years agoKVM: selftests: Fix build for evmcs.h
Peter Xu [Mon, 4 May 2020 22:06:07 +0000 (18:06 -0400)]
KVM: selftests: Fix build for evmcs.h

I got this error when building kvm selftests:

/usr/bin/ld: /home/xz/git/linux/tools/testing/selftests/kvm/libkvm.a(vmx.o):/home/xz/git/linux/tools/testing/selftests/kvm/include/evmcs.h:222: multiple definition of `current_evmcs'; /tmp/cco1G48P.o:/home/xz/git/linux/tools/testing/selftests/kvm/include/evmcs.h:222: first defined here
/usr/bin/ld: /home/xz/git/linux/tools/testing/selftests/kvm/libkvm.a(vmx.o):/home/xz/git/linux/tools/testing/selftests/kvm/include/evmcs.h:223: multiple definition of `current_vp_assist'; /tmp/cco1G48P.o:/home/xz/git/linux/tools/testing/selftests/kvm/include/evmcs.h:223: first defined here

I think it's because evmcs.h is included both in a test file and a lib file so
the structs have multiple declarations when linking.  After all it's not a good
habit to declare structs in the header files.

Cc: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
Message-Id: <20200504220607.99627-1-peterx@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
4 years agokvm: x86: Use KVM CPU capabilities to determine CR4 reserved bits
Paolo Bonzini [Tue, 5 May 2020 13:40:46 +0000 (09:40 -0400)]
kvm: x86: Use KVM CPU capabilities to determine CR4 reserved bits

Using CPUID data can be useful for the processor compatibility
check, but that's it.  Using it to compute guest-reserved bits
can have both false positives (such as LA57 and UMIP which we
are already handling) and false negatives: in particular, with
this patch we don't allow anymore a KVM guest to set CR4.PKE
when CR4.PKE is clear on the host.

Fixes: b9dd21e104bc ("KVM: x86: simplify handling of PKRU")
Reported-by: Jim Mattson <jmattson@google.com>
Tested-by: Jim Mattson <jmattson@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
4 years agoKVM: VMX: Explicitly clear RFLAGS.CF and RFLAGS.ZF in VM-Exit RSB path
Sean Christopherson [Wed, 6 May 2020 03:53:55 +0000 (20:53 -0700)]
KVM: VMX: Explicitly clear RFLAGS.CF and RFLAGS.ZF in VM-Exit RSB path

Clear CF and ZF in the VM-Exit path after doing __FILL_RETURN_BUFFER so
that KVM doesn't interpret clobbered RFLAGS as a VM-Fail.  Filling the
RSB has always clobbered RFLAGS, its current incarnation just happens
clear CF and ZF in the processs.  Relying on the macro to clear CF and
ZF is extremely fragile, e.g. commit 089dd8e53126e ("x86/speculation:
Change FILL_RETURN_BUFFER to work with objtool") tweaks the loop such
that the ZF flag is always set.

Reported-by: Qian Cai <cai@lca.pw>
Cc: Rick Edgecombe <rick.p.edgecombe@intel.com>
Cc: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: stable@vger.kernel.org
Fixes: f2fde6a5bcfcf ("KVM: VMX: Move RSB stuffing to before the first RET after VM-Exit")
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Message-Id: <20200506035355.2242-1-sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
4 years agodocs/virt/kvm: Document configuring and running nested guests
Kashyap Chamarthy [Tue, 5 May 2020 11:28:39 +0000 (13:28 +0200)]
docs/virt/kvm: Document configuring and running nested guests

This is a rewrite of this[1] Wiki page with further enhancements.  The
doc also includes a section on debugging problems in nested
environments, among other improvements.

[1] https://www.linux-kvm.org/page/Nested_Guests

Signed-off-by: Kashyap Chamarthy <kchamart@redhat.com>
Message-Id: <20200505112839.30534-1-kchamart@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
4 years agoMerge tag 'platform-drivers-x86-v5.7-2' of git://git.infradead.org/linux-platform...
Linus Torvalds [Tue, 5 May 2020 23:29:03 +0000 (16:29 -0700)]
Merge tag 'platform-drivers-x86-v5.7-2' of git://git.infradead.org/linux-platform-drivers-x86

Pull x86 platform driver fixes from Andy Shevchenko:

 - Avoid loading asus-nb-wmi module on selected laptop models

 - Fix S0ix debug support for Jasper Lake PMC

 - Few fixes which have been reported by Hulk bot and others

* tag 'platform-drivers-x86-v5.7-2' of git://git.infradead.org/linux-platform-drivers-x86:
  platform/x86: thinkpad_acpi: Remove always false 'value < 0' statement
  platform/x86: intel_pmc_core: avoid unused-function warnings
  platform/x86: asus-nb-wmi: Do not load on Asus T100TA and T200TA
  platform/x86: intel_pmc_core: Change Jasper Lake S0ix debug reg map back to ICL
  platform/x86/intel-uncore-freq: make uncore_root_kobj static
  platform/x86: wmi: Make two functions static
  platform/x86: surface3_power: Fix a NULL vs IS_ERR() check in probe

4 years agoneigh: send protocol value in neighbor create notification
Roman Mashak [Sat, 2 May 2020 01:34:18 +0000 (21:34 -0400)]
neigh: send protocol value in neighbor create notification

When a new neighbor entry has been added, event is generated but it does not
include protocol, because its value is assigned after the event notification
routine has run, so move protocol assignment code earlier.

Fixes: df9b0e30d44c ("neighbor: Add protocol attribute")
Cc: David Ahern <dsahern@gmail.com>
Signed-off-by: Roman Mashak <mrv@mojatatu.com>
Reviewed-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
4 years agodrm/amd/display: Prevent dpcd reads with passive dongles
Aurabindo Pillai [Wed, 22 Apr 2020 18:37:33 +0000 (14:37 -0400)]
drm/amd/display: Prevent dpcd reads with passive dongles

[why]
During hotplug, a DP port may be connected to the sink through
passive adapter which does not support DPCD reads. Issuing reads
without checking for this condition will result in errors

[how]
Ensure the link is in aux_mode before initiating operation that result
in a DPCD read.

Signed-off-by: Aurabindo Pillai <aurabindo.pillai@amd.com>
Reviewed-by: Harry Wentland <Harry.Wentland@amd.com>
Acked-by: Aurabindo Pillai <aurabindo.pillai@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
4 years agodrm/amd/display: fix counter in wait_for_no_pipes_pending
Roman Li [Wed, 26 Feb 2020 22:30:29 +0000 (17:30 -0500)]
drm/amd/display: fix counter in wait_for_no_pipes_pending

[Why]
Wait counter is not being reset for each pipe.

[How]
Move counter reset into pipe loop scope.

Signed-off-by: Roman Li <roman.li@amd.com>
Reviewed-by: Zhan Liu <Zhan.Liu@amd.com>
Acked-by: Aurabindo Pillai <aurabindo.pillai@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
4 years agodrm/amd/display: Update DCN2.1 DV Code Revision
Sung Lee [Mon, 20 Apr 2020 15:38:30 +0000 (11:38 -0400)]
drm/amd/display: Update DCN2.1 DV Code Revision

[WHY & HOW]
There is a problem in hscale_pixel_rate, the bug
causes DCN to be more optimistic (more likely to underflow)
in upscale cases during prefetch.
This commit ports the fix from DV code to address these issues.

Signed-off-by: Sung Lee <sung.lee@amd.com>
Reviewed-by: Dmytro Laktyushkin <Dmytro.Laktyushkin@amd.com>
Acked-by: Aurabindo Pillai <aurabindo.pillai@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
4 years agoio_uring: handle -EFAULT properly in io_uring_setup()
Xiaoguang Wang [Tue, 5 May 2020 08:28:53 +0000 (16:28 +0800)]
io_uring: handle -EFAULT properly in io_uring_setup()

If copy_to_user() in io_uring_setup() failed, we'll leak many kernel
resources, which will be recycled until process terminates. This bug
can be reproduced by using mprotect to set params to PROT_READ. To fix
this issue, refactor io_uring_create() a bit to add a new 'struct
io_uring_params __user *params' parameter and move the copy_to_user()
in io_uring_setup() to io_uring_setup(), if copy_to_user() failed,
we can free kernel resource properly.

Suggested-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Xiaoguang Wang <xiaoguang.wang@linux.alibaba.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
4 years agonet: broadcom: fix a mistake about ioremap resource
Dejin Zheng [Tue, 5 May 2020 02:03:29 +0000 (10:03 +0800)]
net: broadcom: fix a mistake about ioremap resource

Commit d7a5502b0bb8b ("net: broadcom: convert to
devm_platform_ioremap_resource_byname()") will broke this driver.
idm_base and nicpm_base were optional, after this change, they are
mandatory. it will probe fails with -22 when the dtb doesn't have them
defined. so revert part of this commit and make idm_base and nicpm_base
as optional.

Fixes: d7a5502b0bb8bde ("net: broadcom: convert to devm_platform_ioremap_resource_byname()")
Reported-by: Jonathan Richardson <jonathan.richardson@broadcom.com>
Cc: Scott Branden <scott.branden@broadcom.com>
Cc: Ray Jui <ray.jui@broadcom.com>
Cc: Florian Fainelli <f.fainelli@gmail.com>
Cc: David S. Miller <davem@davemloft.net>
Signed-off-by: Dejin Zheng <zhengdejin5@gmail.com>
Acked-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
4 years agodrm: Fix HDCP failures when SRM fw is missing
Sean Paul [Tue, 14 Apr 2020 19:02:55 +0000 (15:02 -0400)]
drm: Fix HDCP failures when SRM fw is missing

The SRM cleanup in 79643fddd6eb2 ("drm/hdcp: optimizing the srm
handling") inadvertently altered the behavior of HDCP auth when
the SRM firmware is missing. Before that patch, missing SRM was
interpreted as the device having no revoked keys. With that patch,
if the SRM fw file is missing we reject _all_ keys.

This patch fixes that regression by returning success if the file
cannot be found. It also checks the return value from request_srm such
that we won't end up trying to parse the ksv list if there is an error
fetching it.

Fixes: 79643fddd6eb ("drm/hdcp: optimizing the srm handling")
Cc: stable@vger.kernel.org
Cc: Ramalingam C <ramalingam.c@intel.com>
Cc: Sean Paul <sean@poorly.run>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Maxime Ripard <mripard@kernel.org>
Cc: Thomas Zimmermann <tzimmermann@suse.de>
Cc: David Airlie <airlied@linux.ie>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: dri-devel@lists.freedesktop.org
Reviewed-by: Ramalingam C <ramalingam.c@intel.com>
Signed-off-by: Sean Paul <seanpaul@chromium.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20200414190258.38873-1-sean@poorly.run
Changes in v2:
-Noticed a couple other things to clean up
Reviewed-by: Ramalingam C <ramalingam.c@intel.com>
4 years agobus: mhi: core: Fix channel device name conflict
Jeffrey Hugo [Thu, 30 Apr 2020 19:05:55 +0000 (00:35 +0530)]
bus: mhi: core: Fix channel device name conflict

When multiple instances of the same MHI product are present in a system,
we can see a splat from mhi_create_devices() - "sysfs: cannot create
duplicate filename".

This is because the device names assigned to the MHI channel devices are
non-unique.  They consist of the channel's name, and the channel's pipe
id.  For identical products, each instance is going to have the same
set of channel (both in name and pipe id).

To fix this, we prepend the device name of the parent device that the
MHI channels belong to.  Since different instances of the same product
should have unique device names, this makes the MHI channel devices for
each product also unique.

Additionally, remove the pipe id from the MHI channel device name.  This
is an internal detail to the MHI product that provides little value, and
imposes too much device specific internal details to userspace.  It is
expected that channel with a specific name (ie "SAHARA") has a specific
client, and it does not matter what pipe id that channel is enumerated on.
The pipe id is an internal detail between the MHI bus, and the hardware.
The client is not expected to make decisions based on the pipe id, and to
do so would require the client to have intimate knowledge of the hardware,
which is inappropiate as it may violate the layering provided by the MHI
bus.  The limitation of doing this is that each product may only have one
instance of a channel by a unique name.  This limitation is appropriate
given the usecases of MHI channels.

Signed-off-by: Jeffrey Hugo <jhugo@codeaurora.org>
Reviewed-by: Hemant Kumar <hemantk@codeaurora.org>
Reviewed-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Link: https://lore.kernel.org/r/20200430190555.32741-7-manivannan.sadhasivam@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
4 years agobus: mhi: core: Fix typo in comment
Jeffrey Hugo [Thu, 30 Apr 2020 19:05:54 +0000 (00:35 +0530)]
bus: mhi: core: Fix typo in comment

There is a typo - "runtimet" should be "runtime".  Fix it.

Signed-off-by: Jeffrey Hugo <jhugo@codeaurora.org>
Reviewed-by: Hemant Kumar <hemantk@codeaurora.org>
Reviewed-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Link: https://lore.kernel.org/r/20200430190555.32741-6-manivannan.sadhasivam@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
4 years agobus: mhi: core: Offload register accesses to the controller
Jeffrey Hugo [Thu, 30 Apr 2020 19:05:53 +0000 (00:35 +0530)]
bus: mhi: core: Offload register accesses to the controller

When reading or writing MHI registers, the core assumes that the physical
link is a memory mapped PCI link.  This assumption may not hold for all
MHI devices.  The controller knows what is the physical link (ie PCI, I2C,
SPI, etc), and therefore knows the proper methods to access that link.
The controller can also handle link specific error scenarios, such as
reading -1 when the PCI link went down.

Therefore, it is appropriate that the MHI core requests the controller to
make register accesses on behalf of the core, which abstracts the core
from link specifics, and end up removing an unnecessary assumption.

Signed-off-by: Jeffrey Hugo <jhugo@codeaurora.org>
Reviewed-by: Hemant Kumar <hemantk@codeaurora.org>
Reviewed-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Link: https://lore.kernel.org/r/20200430190555.32741-5-manivannan.sadhasivam@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
4 years agobus: mhi: core: Remove link_status() callback
Jeffrey Hugo [Thu, 30 Apr 2020 19:05:52 +0000 (00:35 +0530)]
bus: mhi: core: Remove link_status() callback

If the MHI core detects invalid data due to a PCI read, it calls into
the controller via link_status() to double check that the link is infact
down.  All in all, this is pretty pointless, and racy.  There are no good
reasons for this, and only drawbacks.

Its pointless because chances are, the controller is going to do the same
thing to determine if the link is down - attempt a PCI access and compare
the result.  This does not make the link status decision any smarter.

Its racy because its possible that the link was down at the time of the
MHI core access, but then recovered before the controller access.  In this
case, the controller will indicate the link is not down, and the MHI core
will precede to use a bad value as the MHI core does not attempt to retry
the access.

Retrying the access in the MHI core is a bad idea because again, it is
racy - what if the link is down again?  Furthermore, there may be some
higher level state associated with the link status, that is now invalid
because the link went down.

The only reason why the MHI core could see "invalid" data when doing a PCI
access, that is actually valid, is if the register actually contained the
PCI spec defined sentinel for an invalid access.  In this case, it is
arguable that the MHI implementation broken, and should be fixed, not
worked around.

Therefore, remove the link_status() callback before anyone attempts to
implement it.

Signed-off-by: Jeffrey Hugo <jhugo@codeaurora.org>
Reviewed-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Reviewed-by: Hemant Kumar <hemantk@codeaurora.org>
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Link: https://lore.kernel.org/r/20200430190555.32741-4-manivannan.sadhasivam@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>