Andy Lutomirski [Fri, 15 Dec 2017 21:08:18 +0000 (22:08 +0100)]
x86/mm/pti: Map ESPFIX into user space
Map the ESPFIX pages into user space when PTI is enabled.
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: David Laight <David.Laight@aculab.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Thomas Gleixner [Mon, 4 Dec 2017 14:07:47 +0000 (15:07 +0100)]
x86/mm/pti: Share entry text PMD
Share the entry text PMD of the kernel mapping with the user space
mapping. If large pages are enabled this is a single PMD entry and at the
point where it is copied into the user page table the RW bit has not been
cleared yet. Clear it right away so the user space visible map becomes RX.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: David Laight <David.Laight@aculab.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Eduardo Valentin <eduval@amazon.com>
Cc: Greg KH <gregkh@linuxfoundation.org>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Will Deacon <will.deacon@arm.com>
Cc: aliguori@amazon.com
Cc: daniel.gruss@iaik.tugraz.at
Cc: hughd@google.com
Cc: keescook@google.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Thomas Gleixner [Mon, 4 Dec 2017 14:07:46 +0000 (15:07 +0100)]
x86/entry: Align entry text section to PMD boundary
The (irq)entry text must be visible in the user space page tables. To allow
simple PMD based sharing, make the entry text PMD aligned.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: David Laight <David.Laight@aculab.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Eduardo Valentin <eduval@amazon.com>
Cc: Greg KH <gregkh@linuxfoundation.org>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Will Deacon <will.deacon@arm.com>
Cc: aliguori@amazon.com
Cc: daniel.gruss@iaik.tugraz.at
Cc: hughd@google.com
Cc: keescook@google.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Andy Lutomirski [Mon, 4 Dec 2017 14:07:45 +0000 (15:07 +0100)]
x86/mm/pti: Share cpu_entry_area with user space page tables
Share the cpu entry area so the user space and kernel space page tables
have the same P4D page.
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: David Laight <David.Laight@aculab.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Eduardo Valentin <eduval@amazon.com>
Cc: Greg KH <gregkh@linuxfoundation.org>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Will Deacon <will.deacon@arm.com>
Cc: aliguori@amazon.com
Cc: daniel.gruss@iaik.tugraz.at
Cc: hughd@google.com
Cc: keescook@google.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Thomas Gleixner [Mon, 4 Dec 2017 14:07:43 +0000 (15:07 +0100)]
x86/mm/pti: Force entry through trampoline when PTI active
Force the entry through the trampoline only when PTI is active. Otherwise
go through the normal entry code.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Borislav Petkov <bp@suse.de>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: David Laight <David.Laight@aculab.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Eduardo Valentin <eduval@amazon.com>
Cc: Greg KH <gregkh@linuxfoundation.org>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Will Deacon <will.deacon@arm.com>
Cc: aliguori@amazon.com
Cc: daniel.gruss@iaik.tugraz.at
Cc: hughd@google.com
Cc: keescook@google.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Andy Lutomirski [Mon, 4 Dec 2017 14:07:42 +0000 (15:07 +0100)]
x86/mm/pti: Add functions to clone kernel PMDs
Provide infrastructure to:
- find a kernel PMD for a mapping which must be visible to user space for
the entry/exit code to work.
- walk an address range and share the kernel PMD with it.
This reuses a small part of the original KAISER patches to populate the
user space page table.
[ tglx: Made it universally usable so it can be used for any kind of shared
mapping. Add a mechanism to clear specific bits in the user space
visible PMD entry. Folded Andys simplifactions ]
Originally-by: Dave Hansen <dave.hansen@linux.intel.com>
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Borislav Petkov <bpetkov@suse.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: David Laight <David.Laight@aculab.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Eduardo Valentin <eduval@amazon.com>
Cc: Greg KH <gregkh@linuxfoundation.org>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Will Deacon <will.deacon@arm.com>
Cc: aliguori@amazon.com
Cc: daniel.gruss@iaik.tugraz.at
Cc: hughd@google.com
Cc: keescook@google.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Dave Hansen [Mon, 4 Dec 2017 14:07:40 +0000 (15:07 +0100)]
x86/mm/pti: Populate user PGD
In clone_pgd_range() copy the init user PGDs which cover the kernel half of
the address space, so a process has all the required kernel mappings
visible.
[ tglx: Split out from the big kaiser dump and folded Andys simplification ]
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Borislav Petkov <bp@suse.de>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: David Laight <David.Laight@aculab.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Eduardo Valentin <eduval@amazon.com>
Cc: Greg KH <gregkh@linuxfoundation.org>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Will Deacon <will.deacon@arm.com>
Cc: aliguori@amazon.com
Cc: daniel.gruss@iaik.tugraz.at
Cc: hughd@google.com
Cc: keescook@google.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Dave Hansen [Mon, 4 Dec 2017 14:07:39 +0000 (15:07 +0100)]
x86/mm/pti: Allocate a separate user PGD
Kernel page table isolation requires to have two PGDs. One for the kernel,
which contains the full kernel mapping plus the user space mapping and one
for user space which contains the user space mappings and the minimal set
of kernel mappings which are required by the architecture to be able to
transition from and to user space.
Add the necessary preliminaries.
[ tglx: Split out from the big kaiser dump. EFI fixup from Kirill ]
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Borislav Petkov <bp@suse.de>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: David Laight <David.Laight@aculab.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Eduardo Valentin <eduval@amazon.com>
Cc: Greg KH <gregkh@linuxfoundation.org>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Will Deacon <will.deacon@arm.com>
Cc: aliguori@amazon.com
Cc: daniel.gruss@iaik.tugraz.at
Cc: hughd@google.com
Cc: keescook@google.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Dave Hansen [Mon, 4 Dec 2017 14:07:38 +0000 (15:07 +0100)]
x86/mm/pti: Allow NX poison to be set in p4d/pgd
With PAGE_TABLE_ISOLATION the user portion of the kernel page tables is
poisoned with the NX bit so if the entry code exits with the kernel page
tables selected in CR3, userspace crashes.
But doing so trips the p4d/pgd_bad() checks. Make sure it does not do
that.
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Borislav Petkov <bp@suse.de>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: David Laight <David.Laight@aculab.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Eduardo Valentin <eduval@amazon.com>
Cc: Greg KH <gregkh@linuxfoundation.org>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Will Deacon <will.deacon@arm.com>
Cc: aliguori@amazon.com
Cc: daniel.gruss@iaik.tugraz.at
Cc: hughd@google.com
Cc: keescook@google.com
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Dave Hansen [Mon, 4 Dec 2017 14:07:37 +0000 (15:07 +0100)]
x86/mm/pti: Add mapping helper functions
Add the pagetable helper functions do manage the separate user space page
tables.
[ tglx: Split out from the big combo kaiser patch. Folded Andys
simplification and made it out of line as Boris suggested ]
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: David Laight <David.Laight@aculab.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Eduardo Valentin <eduval@amazon.com>
Cc: Greg KH <gregkh@linuxfoundation.org>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Will Deacon <will.deacon@arm.com>
Cc: aliguori@amazon.com
Cc: daniel.gruss@iaik.tugraz.at
Cc: hughd@google.com
Cc: keescook@google.com
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Borislav Petkov [Tue, 12 Dec 2017 13:39:52 +0000 (14:39 +0100)]
x86/pti: Add the pti= cmdline option and documentation
Keep the "nopti" optional for traditional reasons.
[ tglx: Don't allow force on when running on XEN PV and made 'on'
printout conditional ]
Requested-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Andy Lutomirsky <luto@kernel.org>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: David Laight <David.Laight@aculab.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Eduardo Valentin <eduval@amazon.com>
Cc: Greg KH <gregkh@linuxfoundation.org>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Will Deacon <will.deacon@arm.com>
Cc: aliguori@amazon.com
Cc: daniel.gruss@iaik.tugraz.at
Cc: hughd@google.com
Cc: keescook@google.com
Link: https://lkml.kernel.org/r/20171212133952.10177-1-bp@alien8.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Thomas Gleixner [Mon, 4 Dec 2017 14:07:36 +0000 (15:07 +0100)]
x86/mm/pti: Add infrastructure for page table isolation
Add the initial files for kernel page table isolation, with a minimal init
function and the boot time detection for this misfeature.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Borislav Petkov <bp@suse.de>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: David Laight <David.Laight@aculab.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Eduardo Valentin <eduval@amazon.com>
Cc: Greg KH <gregkh@linuxfoundation.org>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Will Deacon <will.deacon@arm.com>
Cc: aliguori@amazon.com
Cc: daniel.gruss@iaik.tugraz.at
Cc: hughd@google.com
Cc: keescook@google.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Dave Hansen [Mon, 4 Dec 2017 14:07:35 +0000 (15:07 +0100)]
x86/mm/pti: Prepare the x86/entry assembly code for entry/exit CR3 switching
PAGE_TABLE_ISOLATION needs to switch to a different CR3 value when it
enters the kernel and switch back when it exits. This essentially needs to
be done before leaving assembly code.
This is extra challenging because the switching context is tricky: the
registers that can be clobbered can vary. It is also hard to store things
on the stack because there is an established ABI (ptregs) or the stack is
entirely unsafe to use.
Establish a set of macros that allow changing to the user and kernel CR3
values.
Interactions with SWAPGS:
Previous versions of the PAGE_TABLE_ISOLATION code relied on having
per-CPU scratch space to save/restore a register that can be used for the
CR3 MOV. The %GS register is used to index into our per-CPU space, so
SWAPGS *had* to be done before the CR3 switch. That scratch space is gone
now, but the semantic that SWAPGS must be done before the CR3 MOV is
retained. This is good to keep because it is not that hard to do and it
allows to do things like add per-CPU debugging information.
What this does in the NMI code is worth pointing out. NMIs can interrupt
*any* context and they can also be nested with NMIs interrupting other
NMIs. The comments below ".Lnmi_from_kernel" explain the format of the
stack during this situation. Changing the format of this stack is hard.
Instead of storing the old CR3 value on the stack, this depends on the
*regular* register save/restore mechanism and then uses %r14 to keep CR3
during the NMI. It is callee-saved and will not be clobbered by the C NMI
handlers that get called.
[ PeterZ: ESPFIX optimization ]
Based-on-code-from: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: David Laight <David.Laight@aculab.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Eduardo Valentin <eduval@amazon.com>
Cc: Greg KH <gregkh@linuxfoundation.org>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Will Deacon <will.deacon@arm.com>
Cc: aliguori@amazon.com
Cc: daniel.gruss@iaik.tugraz.at
Cc: hughd@google.com
Cc: keescook@google.com
Cc: linux-mm@kvack.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Dave Hansen [Mon, 4 Dec 2017 14:07:34 +0000 (15:07 +0100)]
x86/mm/pti: Disable global pages if PAGE_TABLE_ISOLATION=y
Global pages stay in the TLB across context switches. Since all contexts
share the same kernel mapping, these mappings are marked as global pages
so kernel entries in the TLB are not flushed out on a context switch.
But, even having these entries in the TLB opens up something that an
attacker can use, such as the double-page-fault attack:
http://www.ieee-security.org/TC/SP2013/papers/
4977a191.pdf
That means that even when PAGE_TABLE_ISOLATION switches page tables
on return to user space the global pages would stay in the TLB cache.
Disable global pages so that kernel TLB entries can be flushed before
returning to user space. This way, all accesses to kernel addresses from
userspace result in a TLB miss independent of the existence of a kernel
mapping.
Suppress global pages via the __supported_pte_mask. The user space
mappings set PAGE_GLOBAL for the minimal kernel mappings which are
required for entry/exit. These mappings are set up manually so the
filtering does not take place.
[ The __supported_pte_mask simplification was written by Thomas Gleixner. ]
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Borislav Petkov <bp@suse.de>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: David Laight <David.Laight@aculab.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Eduardo Valentin <eduval@amazon.com>
Cc: Greg KH <gregkh@linuxfoundation.org>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Will Deacon <will.deacon@arm.com>
Cc: aliguori@amazon.com
Cc: daniel.gruss@iaik.tugraz.at
Cc: hughd@google.com
Cc: keescook@google.com
Cc: linux-mm@kvack.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Thomas Gleixner [Mon, 4 Dec 2017 14:07:33 +0000 (15:07 +0100)]
x86/cpufeatures: Add X86_BUG_CPU_INSECURE
Many x86 CPUs leak information to user space due to missing isolation of
user space and kernel space page tables. There are many well documented
ways to exploit that.
The upcoming software migitation of isolating the user and kernel space
page tables needs a misfeature flag so code can be made runtime
conditional.
Add the BUG bits which indicates that the CPU is affected and add a feature
bit which indicates that the software migitation is enabled.
Assume for now that _ALL_ x86 CPUs are affected by this. Exceptions can be
made later.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: David Laight <David.Laight@aculab.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Eduardo Valentin <eduval@amazon.com>
Cc: Greg KH <gregkh@linuxfoundation.org>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Will Deacon <will.deacon@arm.com>
Cc: aliguori@amazon.com
Cc: daniel.gruss@iaik.tugraz.at
Cc: hughd@google.com
Cc: keescook@google.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Thomas Gleixner [Sat, 23 Dec 2017 18:45:11 +0000 (19:45 +0100)]
x86/cpu_entry_area: Prevent wraparound in setup_cpu_entry_area_ptes() on 32bit
The loop which populates the CPU entry area PMDs can wrap around on 32bit
machines when the number of CPUs is small.
It worked wonderful for NR_CPUS=64 for whatever reason and the moron who
wrote that code did not bother to test it with !SMP.
Check for the wraparound to fix it.
Fixes: 92a0f81d8957 ("x86/cpu_entry_area: Move it out of the fixmap")
Reported-by: kernel test robot <fengguang.wu@intel.com>
Signed-off-by: Thomas "Feels stupid" Gleixner <tglx@linutronix.de>
Tested-by: Borislav Petkov <bp@alien8.de>
Thomas Gleixner [Sun, 17 Dec 2017 09:56:29 +0000 (10:56 +0100)]
init: Invoke init_espfix_bsp() from mm_init()
init_espfix_bsp() needs to be invoked before the page table isolation
initialization. Move it into mm_init() which is the place where pti_init()
will be added.
While at it get rid of the #ifdeffery and provide proper stub functions.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Thomas Gleixner [Wed, 20 Dec 2017 17:51:31 +0000 (18:51 +0100)]
x86/cpu_entry_area: Move it out of the fixmap
Put the cpu_entry_area into a separate P4D entry. The fixmap gets too big
and 0-day already hit a case where the fixmap PTEs were cleared by
cleanup_highmap().
Aside of that the fixmap API is a pain as it's all backwards.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Thomas Gleixner [Wed, 20 Dec 2017 17:28:54 +0000 (18:28 +0100)]
x86/cpu_entry_area: Move it to a separate unit
Separate the cpu_entry_area code out of cpu/common.c and the fixmap.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Peter Zijlstra [Tue, 5 Dec 2017 12:34:47 +0000 (13:34 +0100)]
x86/mm: Create asm/invpcid.h
Unclutter tlbflush.h a little.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: David Laight <David.Laight@aculab.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Eduardo Valentin <eduval@amazon.com>
Cc: Greg KH <gregkh@linuxfoundation.org>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will.deacon@arm.com>
Cc: aliguori@amazon.com
Cc: daniel.gruss@iaik.tugraz.at
Cc: hughd@google.com
Cc: keescook@google.com
Cc: linux-mm@kvack.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Dave Hansen [Mon, 4 Dec 2017 14:07:56 +0000 (15:07 +0100)]
x86/mm: Put MMU to hardware ASID translation in one place
There are effectively two ASID types:
1. The one stored in the mmu_context that goes from 0..5
2. The one programmed into the hardware that goes from 1..6
This consolidates the locations where converting between the two (by doing
a +1) to a single place which gives us a nice place to comment.
PAGE_TABLE_ISOLATION will also need to, given an ASID, know which hardware
ASID to flush for the userspace mapping.
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: David Laight <David.Laight@aculab.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Eduardo Valentin <eduval@amazon.com>
Cc: Greg KH <gregkh@linuxfoundation.org>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Will Deacon <will.deacon@arm.com>
Cc: aliguori@amazon.com
Cc: daniel.gruss@iaik.tugraz.at
Cc: hughd@google.com
Cc: keescook@google.com
Cc: linux-mm@kvack.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Dave Hansen [Mon, 4 Dec 2017 14:07:55 +0000 (15:07 +0100)]
x86/mm: Remove hard-coded ASID limit checks
First, it's nice to remove the magic numbers.
Second, PAGE_TABLE_ISOLATION is going to consume half of the available ASID
space. The space is currently unused, but add a comment to spell out this
new restriction.
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: David Laight <David.Laight@aculab.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Eduardo Valentin <eduval@amazon.com>
Cc: Greg KH <gregkh@linuxfoundation.org>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Will Deacon <will.deacon@arm.com>
Cc: aliguori@amazon.com
Cc: daniel.gruss@iaik.tugraz.at
Cc: hughd@google.com
Cc: keescook@google.com
Cc: linux-mm@kvack.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Dave Hansen [Mon, 4 Dec 2017 14:07:54 +0000 (15:07 +0100)]
x86/mm: Move the CR3 construction functions to tlbflush.h
For flushing the TLB, the ASID which has been programmed into the hardware
must be known. That differs from what is in 'cpu_tlbstate'.
Add functions to transform the 'cpu_tlbstate' values into to the one
programmed into the hardware (CR3).
It's not easy to include mmu_context.h into tlbflush.h, so just move the
CR3 building over to tlbflush.h.
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: David Laight <David.Laight@aculab.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Eduardo Valentin <eduval@amazon.com>
Cc: Greg KH <gregkh@linuxfoundation.org>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Will Deacon <will.deacon@arm.com>
Cc: aliguori@amazon.com
Cc: daniel.gruss@iaik.tugraz.at
Cc: hughd@google.com
Cc: keescook@google.com
Cc: linux-mm@kvack.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Peter Zijlstra [Tue, 5 Dec 2017 12:34:52 +0000 (13:34 +0100)]
x86/mm: Add comments to clarify which TLB-flush functions are supposed to flush what
Per popular request..
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: David Laight <David.Laight@aculab.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Eduardo Valentin <eduval@amazon.com>
Cc: Greg KH <gregkh@linuxfoundation.org>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Will Deacon <will.deacon@arm.com>
Cc: aliguori@amazon.com
Cc: daniel.gruss@iaik.tugraz.at
Cc: hughd@google.com
Cc: keescook@google.com
Cc: linux-mm@kvack.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Peter Zijlstra [Tue, 5 Dec 2017 12:34:46 +0000 (13:34 +0100)]
x86/mm: Remove superfluous barriers
atomic64_inc_return() already implies smp_mb() before and after.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: David Laight <David.Laight@aculab.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Eduardo Valentin <eduval@amazon.com>
Cc: Greg KH <gregkh@linuxfoundation.org>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Will Deacon <will.deacon@arm.com>
Cc: aliguori@amazon.com
Cc: daniel.gruss@iaik.tugraz.at
Cc: hughd@google.com
Cc: keescook@google.com
Cc: linux-mm@kvack.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Peter Zijlstra [Tue, 5 Dec 2017 12:34:49 +0000 (13:34 +0100)]
x86/mm: Use __flush_tlb_one() for kernel memory
__flush_tlb_single() is for user mappings, __flush_tlb_one() for
kernel mappings.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: David Laight <David.Laight@aculab.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Eduardo Valentin <eduval@amazon.com>
Cc: Greg KH <gregkh@linuxfoundation.org>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Will Deacon <will.deacon@arm.com>
Cc: aliguori@amazon.com
Cc: daniel.gruss@iaik.tugraz.at
Cc: hughd@google.com
Cc: keescook@google.com
Cc: linux-mm@kvack.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Peter Zijlstra [Tue, 5 Dec 2017 12:34:51 +0000 (13:34 +0100)]
x86/microcode: Dont abuse the TLB-flush interface
Commit:
ec400ddeff20 ("x86/microcode_intel_early.c: Early update ucode on Intel's CPU")
... grubbed into tlbflush internals without coherent explanation.
Since it says its a precaution and the SDM doesn't mention anything like
this, take it out back.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: David Laight <David.Laight@aculab.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Eduardo Valentin <eduval@amazon.com>
Cc: Greg KH <gregkh@linuxfoundation.org>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Will Deacon <will.deacon@arm.com>
Cc: aliguori@amazon.com
Cc: daniel.gruss@iaik.tugraz.at
Cc: fenghua.yu@intel.com
Cc: hughd@google.com
Cc: keescook@google.com
Cc: linux-mm@kvack.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Peter Zijlstra [Tue, 5 Dec 2017 12:34:50 +0000 (13:34 +0100)]
x86/uv: Use the right TLB-flush API
Since uv_flush_tlb_others() implements flush_tlb_others() which is
about flushing user mappings, we should use __flush_tlb_single(),
which too is about flushing user mappings.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Andrew Banman <abanman@hpe.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: David Laight <David.Laight@aculab.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Eduardo Valentin <eduval@amazon.com>
Cc: Greg KH <gregkh@linuxfoundation.org>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Travis <mike.travis@hpe.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Will Deacon <will.deacon@arm.com>
Cc: aliguori@amazon.com
Cc: daniel.gruss@iaik.tugraz.at
Cc: hughd@google.com
Cc: keescook@google.com
Cc: linux-mm@kvack.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Dave Hansen [Tue, 5 Dec 2017 01:25:07 +0000 (17:25 -0800)]
x86/entry: Rename SYSENTER_stack to CPU_ENTRY_AREA_entry_stack
If the kernel oopses while on the trampoline stack, it will print
"<SYSENTER>" even if SYSENTER is not involved. That is rather confusing.
The "SYSENTER" stack is used for a lot more than SYSENTER now. Give it a
better string to display in stack dumps, and rename the kernel code to
match.
Also move the 32-bit code over to the new naming even though it still uses
the entry stack only for SYSENTER.
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Borislav Petkov <bp@suse.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Peter Zijlstra [Tue, 5 Dec 2017 12:34:54 +0000 (13:34 +0100)]
x86/doc: Remove obvious weirdnesses from the x86 MM layout documentation
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: David Laight <David.Laight@aculab.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Eduardo Valentin <eduval@amazon.com>
Cc: Greg KH <gregkh@linuxfoundation.org>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Will Deacon <will.deacon@arm.com>
Cc: aliguori@amazon.com
Cc: daniel.gruss@iaik.tugraz.at
Cc: hughd@google.com
Cc: keescook@google.com
Cc: linux-mm@kvack.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Andy Lutomirski [Tue, 12 Dec 2017 15:56:43 +0000 (07:56 -0800)]
x86/mm/64: Improve the memory map documentation
The old docs had the vsyscall range wrong and were missing the fixmap.
Fix both.
There used to be 8 MB reserved for future vsyscalls, but that's long gone.
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: David Laight <David.Laight@aculab.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Kirill A. Shutemov <kirill@shutemov.name>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Thomas Gleixner [Thu, 14 Dec 2017 11:27:31 +0000 (12:27 +0100)]
x86/ldt: Prevent LDT inheritance on exec
The LDT is inherited across fork() or exec(), but that makes no sense
at all because exec() is supposed to start the process clean.
The reason why this happens is that init_new_context_ldt() is called from
init_new_context() which obviously needs to be called for both fork() and
exec().
It would be surprising if anything relies on that behaviour, so it seems to
be safe to remove that misfeature.
Split the context initialization into two parts. Clear the LDT pointer and
initialize the mutex from the general context init and move the LDT
duplication to arch_dup_mmap() which is only called on fork().
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Andy Lutomirsky <luto@kernel.org>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Borislav Petkov <bpetkov@suse.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: David Laight <David.Laight@aculab.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Eduardo Valentin <eduval@amazon.com>
Cc: Greg KH <gregkh@linuxfoundation.org>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Will Deacon <will.deacon@arm.com>
Cc: aliguori@amazon.com
Cc: dan.j.williams@intel.com
Cc: hughd@google.com
Cc: keescook@google.com
Cc: kirill.shutemov@linux.intel.com
Cc: linux-mm@kvack.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Peter Zijlstra [Thu, 14 Dec 2017 11:27:30 +0000 (12:27 +0100)]
x86/ldt: Rework locking
The LDT is duplicated on fork() and on exec(), which is wrong as exec()
should start from a clean state, i.e. without LDT. To fix this the LDT
duplication code will be moved into arch_dup_mmap() which is only called
for fork().
This introduces a locking problem. arch_dup_mmap() holds mmap_sem of the
parent process, but the LDT duplication code needs to acquire
mm->context.lock to access the LDT data safely, which is the reverse lock
order of write_ldt() where mmap_sem nests into context.lock.
Solve this by introducing a new rw semaphore which serializes the
read/write_ldt() syscall operations and use context.lock to protect the
actual installment of the LDT descriptor.
So context.lock stabilizes mm->context.ldt and can nest inside of the new
semaphore or mmap_sem.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Andy Lutomirsky <luto@kernel.org>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Borislav Petkov <bpetkov@suse.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: David Laight <David.Laight@aculab.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Eduardo Valentin <eduval@amazon.com>
Cc: Greg KH <gregkh@linuxfoundation.org>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Will Deacon <will.deacon@arm.com>
Cc: aliguori@amazon.com
Cc: dan.j.williams@intel.com
Cc: hughd@google.com
Cc: keescook@google.com
Cc: kirill.shutemov@linux.intel.com
Cc: linux-mm@kvack.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Thomas Gleixner [Thu, 14 Dec 2017 11:27:29 +0000 (12:27 +0100)]
arch, mm: Allow arch_dup_mmap() to fail
In order to sanitize the LDT initialization on x86 arch_dup_mmap() must be
allowed to fail. Fix up all instances.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Andy Lutomirsky <luto@kernel.org>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Borislav Petkov <bpetkov@suse.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: David Laight <David.Laight@aculab.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Eduardo Valentin <eduval@amazon.com>
Cc: Greg KH <gregkh@linuxfoundation.org>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Will Deacon <will.deacon@arm.com>
Cc: aliguori@amazon.com
Cc: dan.j.williams@intel.com
Cc: hughd@google.com
Cc: keescook@google.com
Cc: kirill.shutemov@linux.intel.com
Cc: linux-mm@kvack.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Andy Lutomirski [Mon, 11 Dec 2017 06:47:20 +0000 (22:47 -0800)]
x86/vsyscall/64: Warn and fail vsyscall emulation in NATIVE mode
If something goes wrong with pagetable setup, vsyscall=native will
accidentally fall back to emulation. Make it warn and fail so that we
notice.
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: David Laight <David.Laight@aculab.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Andy Lutomirski [Mon, 11 Dec 2017 06:47:19 +0000 (22:47 -0800)]
x86/vsyscall/64: Explicitly set _PAGE_USER in the pagetable hierarchy
The kernel is very erratic as to which pagetables have _PAGE_USER set. The
vsyscall page gets lucky: it seems that all of the relevant pagetables are
among the apparently arbitrary ones that set _PAGE_USER. Rather than
relying on chance, just explicitly set _PAGE_USER.
This will let us clean up pagetable setup to stop setting _PAGE_USER. The
added code can also be reused by pagetable isolation to manage the
_PAGE_USER bit in the usermode tables.
[ tglx: Folded paravirt fix from Juergen Gross ]
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: David Laight <David.Laight@aculab.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Thomas Gleixner [Wed, 20 Dec 2017 17:07:42 +0000 (18:07 +0100)]
x86/mm/dump_pagetables: Make the address hints correct and readable
The address hints are a trainwreck. The array entry numbers have to kept
magically in sync with the actual hints, which is doomed as some of the
array members are initialized at runtime via the entry numbers.
Designated initializers have been around before this code was
implemented....
Use the entry numbers to populate the address hints array and add the
missing bits and pieces. Split 32 and 64 bit for readability sake.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Thomas Gleixner [Sat, 16 Dec 2017 00:14:39 +0000 (01:14 +0100)]
x86/mm/dump_pagetables: Check PAGE_PRESENT for real
The check for a present page in printk_prot():
if (!pgprot_val(prot)) {
/* Not present */
is bogus. If a PTE is set to PAGE_NONE then the pgprot_val is not zero and
the entry is decoded in bogus ways, e.g. as RX GLB. That is confusing when
analyzing mapping correctness. Check for the present bit to make an
informed decision.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Thomas Gleixner [Wed, 20 Dec 2017 17:02:34 +0000 (18:02 +0100)]
x86/Kconfig: Limit NR_CPUS on 32-bit to a sane amount
The recent cpu_entry_area changes fail to compile on 32-bit when BIGSMP=y
and NR_CPUS=512, because the fixmap area becomes too big.
Limit the number of CPUs with BIGSMP to 64, which is already way to big for
32-bit, but it's at least a working limitation.
We performed a quick survey of 32-bit-only machines that might be affected
by this change negatively, but found none.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Thomas Gleixner [Mon, 4 Dec 2017 14:07:32 +0000 (15:07 +0100)]
x86/cpufeatures: Make CPU bugs sticky
There is currently no way to force CPU bug bits like CPU feature bits. That
makes it impossible to set a bug bit once at boot and have it stick for all
upcoming CPUs.
Extend the force set/clear arrays to handle bug bits as well.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Borislav Petkov <bp@suse.de>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Borislav Petkov <bpetkov@suse.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: David Laight <David.Laight@aculab.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Eduardo Valentin <eduval@amazon.com>
Cc: Greg KH <gregkh@linuxfoundation.org>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: aliguori@amazon.com
Cc: daniel.gruss@iaik.tugraz.at
Cc: hughd@google.com
Cc: keescook@google.com
Link: https://lkml.kernel.org/r/20171204150606.992156574@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Thomas Gleixner [Mon, 4 Dec 2017 14:07:31 +0000 (15:07 +0100)]
x86/paravirt: Provide a way to check for hypervisors
There is no generic way to test whether a kernel is running on a specific
hypervisor. But that's required to prevent the upcoming user address space
separation feature in certain guest modes.
Make the hypervisor type enum unconditionally available and provide a
helper function which allows to test for a specific type.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Juergen Gross <jgross@suse.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Borislav Petkov <bpetkov@suse.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: David Laight <David.Laight@aculab.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Eduardo Valentin <eduval@amazon.com>
Cc: Greg KH <gregkh@linuxfoundation.org>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: aliguori@amazon.com
Cc: daniel.gruss@iaik.tugraz.at
Cc: hughd@google.com
Cc: keescook@google.com
Link: https://lkml.kernel.org/r/20171204150606.912938129@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Thomas Gleixner [Mon, 4 Dec 2017 14:07:30 +0000 (15:07 +0100)]
x86/paravirt: Dont patch flush_tlb_single
native_flush_tlb_single() will be changed with the upcoming
PAGE_TABLE_ISOLATION feature. This requires to have more code in
there than INVLPG.
Remove the paravirt patching for it.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Josh Poimboeuf <jpoimboe@redhat.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Borislav Petkov <bpetkov@suse.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: David Laight <David.Laight@aculab.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Eduardo Valentin <eduval@amazon.com>
Cc: Greg KH <gregkh@linuxfoundation.org>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: aliguori@amazon.com
Cc: daniel.gruss@iaik.tugraz.at
Cc: hughd@google.com
Cc: keescook@google.com
Cc: linux-mm@kvack.org
Cc: michael.schwarz@iaik.tugraz.at
Cc: moritz.lipp@iaik.tugraz.at
Cc: richard.fellner@student.tugraz.at
Link: https://lkml.kernel.org/r/20171204150606.828111617@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Andy Lutomirski [Mon, 4 Dec 2017 14:07:29 +0000 (15:07 +0100)]
x86/entry/64: Make cpu_entry_area.tss read-only
The TSS is a fairly juicy target for exploits, and, now that the TSS
is in the cpu_entry_area, it's no longer protected by kASLR. Make it
read-only on x86_64.
On x86_32, it can't be RO because it's written by the CPU during task
switches, and we use a task gate for double faults. I'd also be
nervous about errata if we tried to make it RO even on configurations
without double fault handling.
[ tglx: AMD confirmed that there is no problem on 64-bit with TSS RO. So
it's probably safe to assume that it's a non issue, though Intel
might have been creative in that area. Still waiting for
confirmation. ]
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Borislav Petkov <bpetkov@suse.de>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: David Laight <David.Laight@aculab.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Eduardo Valentin <eduval@amazon.com>
Cc: Greg KH <gregkh@linuxfoundation.org>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: aliguori@amazon.com
Cc: daniel.gruss@iaik.tugraz.at
Cc: hughd@google.com
Cc: keescook@google.com
Link: https://lkml.kernel.org/r/20171204150606.733700132@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Andy Lutomirski [Mon, 4 Dec 2017 14:07:28 +0000 (15:07 +0100)]
x86/entry: Clean up the SYSENTER_stack code
The existing code was a mess, mainly because C arrays are nasty. Turn
SYSENTER_stack into a struct, add a helper to find it, and do all the
obvious cleanups this enables.
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Borislav Petkov <bpetkov@suse.de>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: David Laight <David.Laight@aculab.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Eduardo Valentin <eduval@amazon.com>
Cc: Greg KH <gregkh@linuxfoundation.org>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: aliguori@amazon.com
Cc: daniel.gruss@iaik.tugraz.at
Cc: hughd@google.com
Cc: keescook@google.com
Link: https://lkml.kernel.org/r/20171204150606.653244723@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Andy Lutomirski [Mon, 4 Dec 2017 14:07:27 +0000 (15:07 +0100)]
x86/entry/64: Remove the SYSENTER stack canary
Now that the SYSENTER stack has a guard page, there's no need for a canary
to detect overflow after the fact.
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Borislav Petkov <bp@suse.de>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Borislav Petkov <bpetkov@suse.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: David Laight <David.Laight@aculab.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Eduardo Valentin <eduval@amazon.com>
Cc: Greg KH <gregkh@linuxfoundation.org>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: aliguori@amazon.com
Cc: daniel.gruss@iaik.tugraz.at
Cc: hughd@google.com
Cc: keescook@google.com
Link: https://lkml.kernel.org/r/20171204150606.572577316@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Andy Lutomirski [Mon, 4 Dec 2017 14:07:26 +0000 (15:07 +0100)]
x86/entry/64: Move the IST stacks into struct cpu_entry_area
The IST stacks are needed when an IST exception occurs and are accessed
before any kernel code at all runs. Move them into struct cpu_entry_area.
The IST stacks are unlike the rest of cpu_entry_area: they're used even for
entries from kernel mode. This means that they should be set up before we
load the final IDT. Move cpu_entry_area setup to trap_init() for the boot
CPU and set it up for all possible CPUs at once in native_smp_prepare_cpus().
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Borislav Petkov <bp@suse.de>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Borislav Petkov <bpetkov@suse.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: David Laight <David.Laight@aculab.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Eduardo Valentin <eduval@amazon.com>
Cc: Greg KH <gregkh@linuxfoundation.org>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: aliguori@amazon.com
Cc: daniel.gruss@iaik.tugraz.at
Cc: hughd@google.com
Cc: keescook@google.com
Link: https://lkml.kernel.org/r/20171204150606.480598743@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Andy Lutomirski [Mon, 4 Dec 2017 14:07:25 +0000 (15:07 +0100)]
x86/entry/64: Create a per-CPU SYSCALL entry trampoline
Handling SYSCALL is tricky: the SYSCALL handler is entered with every
single register (except FLAGS), including RSP, live. It somehow needs
to set RSP to point to a valid stack, which means it needs to save the
user RSP somewhere and find its own stack pointer. The canonical way
to do this is with SWAPGS, which lets us access percpu data using the
%gs prefix.
With PAGE_TABLE_ISOLATION-like pagetable switching, this is
problematic. Without a scratch register, switching CR3 is impossible, so
%gs-based percpu memory would need to be mapped in the user pagetables.
Doing that without information leaks is difficult or impossible.
Instead, use a different sneaky trick. Map a copy of the first part
of the SYSCALL asm at a different address for each CPU. Now RIP
varies depending on the CPU, so we can use RIP-relative memory access
to access percpu memory. By putting the relevant information (one
scratch slot and the stack address) at a constant offset relative to
RIP, we can make SYSCALL work without relying on %gs.
A nice thing about this approach is that we can easily switch it on
and off if we want pagetable switching to be configurable.
The compat variant of SYSCALL doesn't have this problem in the first
place -- there are plenty of scratch registers, since we don't care
about preserving r8-r15. This patch therefore doesn't touch SYSCALL32
at all.
This patch actually seems to be a small speedup. With this patch,
SYSCALL touches an extra cache line and an extra virtual page, but
the pipeline no longer stalls waiting for SWAPGS. It seems that, at
least in a tight loop, the latter outweights the former.
Thanks to David Laight for an optimization tip.
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Borislav Petkov <bpetkov@suse.de>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: David Laight <David.Laight@aculab.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Eduardo Valentin <eduval@amazon.com>
Cc: Greg KH <gregkh@linuxfoundation.org>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: aliguori@amazon.com
Cc: daniel.gruss@iaik.tugraz.at
Cc: hughd@google.com
Cc: keescook@google.com
Link: https://lkml.kernel.org/r/20171204150606.403607157@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Andy Lutomirski [Mon, 4 Dec 2017 14:07:24 +0000 (15:07 +0100)]
x86/entry/64: Return to userspace from the trampoline stack
By itself, this is useless. It gives us the ability to run some final code
before exit that cannnot run on the kernel stack. This could include a CR3
switch a la PAGE_TABLE_ISOLATION or some kernel stack erasing, for
example. (Or even weird things like *changing* which kernel stack gets
used as an ASLR-strengthening mechanism.)
The SYSRET32 path is not covered yet. It could be in the future or
we could just ignore it and force the slow path if needed.
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Borislav Petkov <bp@suse.de>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Borislav Petkov <bpetkov@suse.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: David Laight <David.Laight@aculab.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Eduardo Valentin <eduval@amazon.com>
Cc: Greg KH <gregkh@linuxfoundation.org>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: aliguori@amazon.com
Cc: daniel.gruss@iaik.tugraz.at
Cc: hughd@google.com
Cc: keescook@google.com
Link: https://lkml.kernel.org/r/20171204150606.306546484@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Andy Lutomirski [Mon, 4 Dec 2017 14:07:23 +0000 (15:07 +0100)]
x86/entry/64: Use a per-CPU trampoline stack for IDT entries
Historically, IDT entries from usermode have always gone directly
to the running task's kernel stack. Rearrange it so that we enter on
a per-CPU trampoline stack and then manually switch to the task's stack.
This touches a couple of extra cachelines, but it gives us a chance
to run some code before we touch the kernel stack.
The asm isn't exactly beautiful, but I think that fully refactoring
it can wait.
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Borislav Petkov <bpetkov@suse.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: David Laight <David.Laight@aculab.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Eduardo Valentin <eduval@amazon.com>
Cc: Greg KH <gregkh@linuxfoundation.org>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: aliguori@amazon.com
Cc: daniel.gruss@iaik.tugraz.at
Cc: hughd@google.com
Cc: keescook@google.com
Link: https://lkml.kernel.org/r/20171204150606.225330557@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Andy Lutomirski [Mon, 4 Dec 2017 14:07:22 +0000 (15:07 +0100)]
x86/espfix/64: Stop assuming that pt_regs is on the entry stack
When we start using an entry trampoline, a #GP from userspace will
be delivered on the entry stack, not on the task stack. Fix the
espfix64 #DF fixup to set up #GP according to TSS.SP0, rather than
assuming that pt_regs + 1 == SP0. This won't change anything
without an entry stack, but it will make the code continue to work
when an entry stack is added.
While we're at it, improve the comments to explain what's actually
going on.
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Borislav Petkov <bp@suse.de>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Borislav Petkov <bpetkov@suse.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: David Laight <David.Laight@aculab.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Eduardo Valentin <eduval@amazon.com>
Cc: Greg KH <gregkh@linuxfoundation.org>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: aliguori@amazon.com
Cc: daniel.gruss@iaik.tugraz.at
Cc: hughd@google.com
Cc: keescook@google.com
Link: https://lkml.kernel.org/r/20171204150606.130778051@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Andy Lutomirski [Mon, 4 Dec 2017 14:07:21 +0000 (15:07 +0100)]
x86/entry/64: Separate cpu_current_top_of_stack from TSS.sp0
On 64-bit kernels, we used to assume that TSS.sp0 was the current
top of stack. With the addition of an entry trampoline, this will
no longer be the case. Store the current top of stack in TSS.sp1,
which is otherwise unused but shares the same cacheline.
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Borislav Petkov <bp@suse.de>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Borislav Petkov <bpetkov@suse.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: David Laight <David.Laight@aculab.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Eduardo Valentin <eduval@amazon.com>
Cc: Greg KH <gregkh@linuxfoundation.org>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: aliguori@amazon.com
Cc: daniel.gruss@iaik.tugraz.at
Cc: hughd@google.com
Cc: keescook@google.com
Link: https://lkml.kernel.org/r/20171204150606.050864668@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Andy Lutomirski [Mon, 4 Dec 2017 14:07:20 +0000 (15:07 +0100)]
x86/entry: Remap the TSS into the CPU entry area
This has a secondary purpose: it puts the entry stack into a region
with a well-controlled layout. A subsequent patch will take
advantage of this to streamline the SYSCALL entry code to be able to
find it more easily.
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Borislav Petkov <bpetkov@suse.de>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: David Laight <David.Laight@aculab.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Eduardo Valentin <eduval@amazon.com>
Cc: Greg KH <gregkh@linuxfoundation.org>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: aliguori@amazon.com
Cc: daniel.gruss@iaik.tugraz.at
Cc: hughd@google.com
Cc: keescook@google.com
Link: https://lkml.kernel.org/r/20171204150605.962042855@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Andy Lutomirski [Mon, 4 Dec 2017 14:07:19 +0000 (15:07 +0100)]
x86/entry: Move SYSENTER_stack to the beginning of struct tss_struct
SYSENTER_stack should have reliable overflow detection, which
means that it needs to be at the bottom of a page, not the top.
Move it to the beginning of struct tss_struct and page-align it.
Also add an assertion to make sure that the fixed hardware TSS
doesn't cross a page boundary.
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Borislav Petkov <bp@suse.de>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Borislav Petkov <bpetkov@suse.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: David Laight <David.Laight@aculab.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Eduardo Valentin <eduval@amazon.com>
Cc: Greg KH <gregkh@linuxfoundation.org>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: aliguori@amazon.com
Cc: daniel.gruss@iaik.tugraz.at
Cc: hughd@google.com
Cc: keescook@google.com
Link: https://lkml.kernel.org/r/20171204150605.881827433@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Andy Lutomirski [Mon, 4 Dec 2017 14:07:18 +0000 (15:07 +0100)]
x86/dumpstack: Handle stack overflow on all stacks
We currently special-case stack overflow on the task stack. We're
going to start putting special stacks in the fixmap with a custom
layout, so they'll have guard pages, too. Teach the unwinder to be
able to unwind an overflow of any of the stacks.
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Borislav Petkov <bp@suse.de>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Borislav Petkov <bpetkov@suse.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: David Laight <David.Laight@aculab.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Eduardo Valentin <eduval@amazon.com>
Cc: Greg KH <gregkh@linuxfoundation.org>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: aliguori@amazon.com
Cc: daniel.gruss@iaik.tugraz.at
Cc: hughd@google.com
Cc: keescook@google.com
Link: https://lkml.kernel.org/r/20171204150605.802057305@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Andy Lutomirski [Mon, 4 Dec 2017 14:07:17 +0000 (15:07 +0100)]
x86/entry: Fix assumptions that the HW TSS is at the beginning of cpu_tss
A future patch will move SYSENTER_stack to the beginning of cpu_tss
to help detect overflow. Before this can happen, fix several code
paths that hardcode assumptions about the old layout.
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Dave Hansen <dave.hansen@intel.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Borislav Petkov <bpetkov@suse.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: David Laight <David.Laight@aculab.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Eduardo Valentin <eduval@amazon.com>
Cc: Greg KH <gregkh@linuxfoundation.org>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: aliguori@amazon.com
Cc: daniel.gruss@iaik.tugraz.at
Cc: hughd@google.com
Cc: keescook@google.com
Link: https://lkml.kernel.org/r/20171204150605.722425540@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Andy Lutomirski [Mon, 4 Dec 2017 14:07:16 +0000 (15:07 +0100)]
x86/kasan/64: Teach KASAN about the cpu_entry_area
The cpu_entry_area will contain stacks. Make sure that KASAN has
appropriate shadow mappings for them.
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Andrey Ryabinin <aryabinin@virtuozzo.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Alexander Potapenko <glider@google.com>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Borislav Petkov <bpetkov@suse.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: David Laight <David.Laight@aculab.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Eduardo Valentin <eduval@amazon.com>
Cc: Greg KH <gregkh@linuxfoundation.org>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: aliguori@amazon.com
Cc: daniel.gruss@iaik.tugraz.at
Cc: hughd@google.com
Cc: kasan-dev@googlegroups.com
Cc: keescook@google.com
Link: https://lkml.kernel.org/r/20171204150605.642806442@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Andy Lutomirski [Mon, 4 Dec 2017 14:07:15 +0000 (15:07 +0100)]
x86/mm/fixmap: Generalize the GDT fixmap mechanism, introduce struct cpu_entry_area
Currently, the GDT is an ad-hoc array of pages, one per CPU, in the
fixmap. Generalize it to be an array of a new 'struct cpu_entry_area'
so that we can cleanly add new things to it.
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Borislav Petkov <bp@suse.de>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Borislav Petkov <bpetkov@suse.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: David Laight <David.Laight@aculab.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Eduardo Valentin <eduval@amazon.com>
Cc: Greg KH <gregkh@linuxfoundation.org>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: aliguori@amazon.com
Cc: daniel.gruss@iaik.tugraz.at
Cc: hughd@google.com
Cc: keescook@google.com
Link: https://lkml.kernel.org/r/20171204150605.563271721@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Andy Lutomirski [Mon, 4 Dec 2017 14:07:14 +0000 (15:07 +0100)]
x86/entry/gdt: Put per-CPU GDT remaps in ascending order
We currently have CPU 0's GDT at the top of the GDT range and
higher-numbered CPUs at lower addresses. This happens because the
fixmap is upside down (index 0 is the top of the fixmap).
Flip it so that GDTs are in ascending order by virtual address.
This will simplify a future patch that will generalize the GDT
remap to contain multiple pages.
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Borislav Petkov <bpetkov@suse.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: David Laight <David.Laight@aculab.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Eduardo Valentin <eduval@amazon.com>
Cc: Greg KH <gregkh@linuxfoundation.org>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: aliguori@amazon.com
Cc: daniel.gruss@iaik.tugraz.at
Cc: hughd@google.com
Cc: keescook@google.com
Link: https://lkml.kernel.org/r/20171204150605.471561421@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Andy Lutomirski [Mon, 4 Dec 2017 14:07:13 +0000 (15:07 +0100)]
x86/dumpstack: Add get_stack_info() support for the SYSENTER stack
get_stack_info() doesn't currently know about the SYSENTER stack, so
unwinding will fail if we entered the kernel on the SYSENTER stack
and haven't fully switched off. Teach get_stack_info() about the
SYSENTER stack.
With future patches applied that run part of the entry code on the
SYSENTER stack and introduce an intentional BUG(), I would get:
PANIC: double fault, error_code: 0x0
...
RIP: 0010:do_error_trap+0x33/0x1c0
...
Call Trace:
Code: ...
With this patch, I get:
PANIC: double fault, error_code: 0x0
...
Call Trace:
<SYSENTER>
? async_page_fault+0x36/0x60
? invalid_op+0x22/0x40
? async_page_fault+0x36/0x60
? sync_regs+0x3c/0x40
? sync_regs+0x2e/0x40
? error_entry+0x6c/0xd0
? async_page_fault+0x36/0x60
</SYSENTER>
Code: ...
which is a lot more informative.
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Borislav Petkov <bp@suse.de>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Borislav Petkov <bpetkov@suse.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: David Laight <David.Laight@aculab.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Eduardo Valentin <eduval@amazon.com>
Cc: Greg KH <gregkh@linuxfoundation.org>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: aliguori@amazon.com
Cc: daniel.gruss@iaik.tugraz.at
Cc: hughd@google.com
Cc: keescook@google.com
Link: https://lkml.kernel.org/r/20171204150605.392711508@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Andy Lutomirski [Mon, 4 Dec 2017 14:07:12 +0000 (15:07 +0100)]
x86/entry/64: Allocate and enable the SYSENTER stack
This will simplify future changes that want scratch variables early in
the SYSENTER handler -- they'll be able to spill registers to the
stack. It also lets us get rid of a SWAPGS_UNSAFE_STACK user.
This does not depend on CONFIG_IA32_EMULATION=y because we'll want the
stack space even without IA32 emulation.
As far as I can tell, the reason that this wasn't done from day 1 is
that we use IST for #DB and #BP, which is IMO rather nasty and causes
a lot more problems than it solves. But, since #DB uses IST, we don't
actually need a real stack for SYSENTER (because SYSENTER with TF set
will invoke #DB on the IST stack rather than the SYSENTER stack).
I want to remove IST usage from these vectors some day, and this patch
is a prerequisite for that as well.
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Borislav Petkov <bp@suse.de>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Borislav Petkov <bpetkov@suse.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: David Laight <David.Laight@aculab.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Eduardo Valentin <eduval@amazon.com>
Cc: Greg KH <gregkh@linuxfoundation.org>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: aliguori@amazon.com
Cc: daniel.gruss@iaik.tugraz.at
Cc: hughd@google.com
Cc: keescook@google.com
Link: https://lkml.kernel.org/r/20171204150605.312726423@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Andy Lutomirski [Mon, 4 Dec 2017 14:07:11 +0000 (15:07 +0100)]
x86/irq/64: Print the offending IP in the stack overflow warning
In case something goes wrong with unwind (not unlikely in case of
overflow), print the offending IP where we detected the overflow.
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Borislav Petkov <bpetkov@suse.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: David Laight <David.Laight@aculab.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Eduardo Valentin <eduval@amazon.com>
Cc: Greg KH <gregkh@linuxfoundation.org>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: aliguori@amazon.com
Cc: daniel.gruss@iaik.tugraz.at
Cc: hughd@google.com
Cc: keescook@google.com
Link: https://lkml.kernel.org/r/20171204150605.231677119@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Andy Lutomirski [Mon, 4 Dec 2017 14:07:10 +0000 (15:07 +0100)]
x86/irq: Remove an old outdated comment about context tracking races
That race has been fixed and code cleaned up for a while now.
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Borislav Petkov <bpetkov@suse.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: David Laight <David.Laight@aculab.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Eduardo Valentin <eduval@amazon.com>
Cc: Greg KH <gregkh@linuxfoundation.org>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: aliguori@amazon.com
Cc: daniel.gruss@iaik.tugraz.at
Cc: hughd@google.com
Cc: keescook@google.com
Link: https://lkml.kernel.org/r/20171204150605.150551639@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Josh Poimboeuf [Mon, 4 Dec 2017 14:07:09 +0000 (15:07 +0100)]
x86/unwinder: Handle stack overflows more gracefully
There are at least two unwinder bugs hindering the debugging of
stack-overflow crashes:
- It doesn't deal gracefully with the case where the stack overflows and
the stack pointer itself isn't on a valid stack but the
to-be-dereferenced data *is*.
- The ORC oops dump code doesn't know how to print partial pt_regs, for the
case where if we get an interrupt/exception in *early* entry code
before the full pt_regs have been saved.
Fix both issues.
http://lkml.kernel.org/r/
20171126024031.uxi4numpbjm5rlbr@treble
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Borislav Petkov <bpetkov@suse.de>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: David Laight <David.Laight@aculab.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Eduardo Valentin <eduval@amazon.com>
Cc: Greg KH <gregkh@linuxfoundation.org>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: aliguori@amazon.com
Cc: daniel.gruss@iaik.tugraz.at
Cc: hughd@google.com
Cc: keescook@google.com
Link: https://lkml.kernel.org/r/20171204150605.071425003@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Andy Lutomirski [Mon, 4 Dec 2017 14:07:08 +0000 (15:07 +0100)]
x86/unwinder/orc: Dont bail on stack overflow
If the stack overflows into a guard page and the ORC unwinder should work
well: by construction, there can't be any meaningful data in the guard page
because no writes to the guard page will have succeeded.
But there is a bug that prevents unwinding from working correctly: if the
starting register state has RSP pointing into a stack guard page, the ORC
unwinder bails out immediately.
Instead of bailing out immediately check whether the next page up is a
valid check page and if so analyze that. As a result the ORC unwinder will
start the unwind.
Tested by intentionally overflowing the task stack. The result is an
accurate call trace instead of a trace consisting purely of '?' entries.
There are a few other bugs that are triggered if the unwinder encounters a
stack overflow after the first step, but they are outside the scope of this
fix.
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Borislav Petkov <bpetkov@suse.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: David Laight <David.Laight@aculab.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Eduardo Valentin <eduval@amazon.com>
Cc: Greg KH <gregkh@linuxfoundation.org>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: aliguori@amazon.com
Cc: daniel.gruss@iaik.tugraz.at
Cc: hughd@google.com
Cc: keescook@google.com
Link: https://lkml.kernel.org/r/20171204150604.991389777@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Boris Ostrovsky [Mon, 4 Dec 2017 14:07:07 +0000 (15:07 +0100)]
x86/entry/64/paravirt: Use paravirt-safe macro to access eflags
Commit
1d3e53e8624a ("x86/entry/64: Refactor IRQ stacks and make them
NMI-safe") added DEBUG_ENTRY_ASSERT_IRQS_OFF macro that acceses eflags
using 'pushfq' instruction when testing for IF bit. On PV Xen guests
looking at IF flag directly will always see it set, resulting in 'ud2'.
Introduce SAVE_FLAGS() macro that will use appropriate save_fl pv op when
running paravirt.
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Juergen Gross <jgross@suse.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Borislav Petkov <bpetkov@suse.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: David Laight <David.Laight@aculab.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Eduardo Valentin <eduval@amazon.com>
Cc: Greg KH <gregkh@linuxfoundation.org>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: aliguori@amazon.com
Cc: daniel.gruss@iaik.tugraz.at
Cc: hughd@google.com
Cc: keescook@google.com
Cc: xen-devel@lists.xenproject.org
Link: https://lkml.kernel.org/r/20171204150604.899457242@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Andrey Ryabinin [Thu, 16 Nov 2017 01:36:35 +0000 (17:36 -0800)]
x86/mm/kasan: Don't use vmemmap_populate() to initialize shadow
[ Note, this is a Git cherry-pick of the following commit:
d17a1d97dc20: ("x86/mm/kasan: don't use vmemmap_populate() to initialize shadow")
... for easier x86 PTI code testing and back-porting. ]
The KASAN shadow is currently mapped using vmemmap_populate() since that
provides a semi-convenient way to map pages into init_top_pgt. However,
since that no longer zeroes the mapped pages, it is not suitable for
KASAN, which requires zeroed shadow memory.
Add kasan_populate_shadow() interface and use it instead of
vmemmap_populate(). Besides, this allows us to take advantage of
gigantic pages and use them to populate the shadow, which should save us
some memory wasted on page tables and reduce TLB pressure.
Link: http://lkml.kernel.org/r/20171103185147.2688-2-pasha.tatashin@oracle.com
Signed-off-by: Andrey Ryabinin <aryabinin@virtuozzo.com>
Signed-off-by: Pavel Tatashin <pasha.tatashin@oracle.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Steven Sistare <steven.sistare@oracle.com>
Cc: Daniel Jordan <daniel.m.jordan@oracle.com>
Cc: Bob Picco <bob.picco@oracle.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Sam Ravnborg <sam@ravnborg.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Will Deacon [Tue, 24 Oct 2017 10:22:48 +0000 (11:22 +0100)]
locking/barriers: Convert users of lockless_dereference() to READ_ONCE()
[ Note, this is a Git cherry-pick of the following commit:
506458efaf15 ("locking/barriers: Convert users of lockless_dereference() to READ_ONCE()")
... for easier x86 PTI code testing and back-porting. ]
READ_ONCE() now has an implicit smp_read_barrier_depends() call, so it
can be used instead of lockless_dereference() without any change in
semantics.
Signed-off-by: Will Deacon <will.deacon@arm.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1508840570-22169-4-git-send-email-will.deacon@arm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Will Deacon [Tue, 24 Oct 2017 10:22:47 +0000 (11:22 +0100)]
locking/barriers: Add implicit smp_read_barrier_depends() to READ_ONCE()
[ Note, this is a Git cherry-pick of the following commit:
76ebbe78f739 ("locking/barriers: Add implicit smp_read_barrier_depends() to READ_ONCE()")
... for easier x86 PTI code testing and back-porting. ]
In preparation for the removal of lockless_dereference(), which is the
same as READ_ONCE() on all architectures other than Alpha, add an
implicit smp_read_barrier_depends() to READ_ONCE() so that it can be
used to head dependency chains on all architectures.
Signed-off-by: Will Deacon <will.deacon@arm.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1508840570-22169-3-git-send-email-will.deacon@arm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Daniel Borkmann [Tue, 12 Dec 2017 01:25:31 +0000 (02:25 +0100)]
bpf: fix build issues on um due to mising bpf_perf_event.h
[ Note, this is a Git cherry-pick of the following commit:
a23f06f06dbe ("bpf: fix build issues on um due to mising bpf_perf_event.h")
... for easier x86 PTI code testing and back-porting. ]
Since
c895f6f703ad ("bpf: correct broken uapi for
BPF_PROG_TYPE_PERF_EVENT program type") um (uml) won't build
on i386 or x86_64:
[...]
CC init/main.o
In file included from ../include/linux/perf_event.h:18:0,
from ../include/linux/trace_events.h:10,
from ../include/trace/syscall.h:7,
from ../include/linux/syscalls.h:82,
from ../init/main.c:20:
../include/uapi/linux/bpf_perf_event.h:11:32: fatal error:
asm/bpf_perf_event.h: No such file or directory #include
<asm/bpf_perf_event.h>
[...]
Lets add missing bpf_perf_event.h also to um arch. This seems
to be the only one still missing.
Fixes: c895f6f703ad ("bpf: correct broken uapi for BPF_PROG_TYPE_PERF_EVENT program type")
Reported-by: Randy Dunlap <rdunlap@infradead.org>
Suggested-by: Richard Weinberger <richard@sigma-star.at>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Tested-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Cc: Richard Weinberger <richard@sigma-star.at>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Richard Weinberger <richard@nod.at>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Andi Kleen [Thu, 31 Aug 2017 21:46:30 +0000 (14:46 -0700)]
perf/x86: Enable free running PEBS for REGS_USER/INTR
[ Note, this is a Git cherry-pick of the following commit:
a47ba4d77e12 ("perf/x86: Enable free running PEBS for REGS_USER/INTR")
... for easier x86 PTI code testing and back-porting. ]
Currently free running PEBS is disabled when user or interrupt
registers are requested. Most of the registers are actually
available in the PEBS record and can be supported.
So we just need to check for the supported registers and then
allow it: it is all except for the segment register.
For user registers this only works when the counter is limited
to ring 3 only, so this also needs to be checked.
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20170831214630.21892-1-andi@firstfloor.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Rudolf Marek [Tue, 28 Nov 2017 21:01:06 +0000 (22:01 +0100)]
x86: Make X86_BUG_FXSAVE_LEAK detectable in CPUID on AMD
[ Note, this is a Git cherry-pick of the following commit:
2b67799bdf25 ("x86: Make X86_BUG_FXSAVE_LEAK detectable in CPUID on AMD")
... for easier x86 PTI code testing and back-porting. ]
The latest AMD AMD64 Architecture Programmer's Manual
adds a CPUID feature XSaveErPtr (CPUID_Fn80000008_EBX[2]).
If this feature is set, the FXSAVE, XSAVE, FXSAVEOPT, XSAVEC, XSAVES
/ FXRSTOR, XRSTOR, XRSTORS always save/restore error pointers,
thus making the X86_BUG_FXSAVE_LEAK workaround obsolete on such CPUs.
Signed-Off-By: Rudolf Marek <r.marek@assembler.cz>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Borislav Petkov <bp@suse.de>
Tested-by: Borislav Petkov <bp@suse.de>
Cc: Andy Lutomirski <luto@amacapital.net>
Link: https://lkml.kernel.org/r/bdcebe90-62c5-1f05-083c-eba7f08b2540@assembler.cz
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Ricardo Neri [Mon, 6 Nov 2017 02:27:51 +0000 (18:27 -0800)]
x86/cpufeature: Add User-Mode Instruction Prevention definitions
[ Note, this is a Git cherry-pick of the following commit: (limited to the cpufeatures.h file)
3522c2a6a4f3 ("x86/cpufeature: Add User-Mode Instruction Prevention definitions")
... for easier x86 PTI code testing and back-porting. ]
User-Mode Instruction Prevention is a security feature present in new
Intel processors that, when set, prevents the execution of a subset of
instructions if such instructions are executed in user mode (CPL > 0).
Attempting to execute such instructions causes a general protection
exception.
The subset of instructions comprises:
* SGDT - Store Global Descriptor Table
* SIDT - Store Interrupt Descriptor Table
* SLDT - Store Local Descriptor Table
* SMSW - Store Machine Status Word
* STR - Store Task Register
This feature is also added to the list of disabled-features to allow
a cleaner handling of build-time configuration.
Signed-off-by: Ricardo Neri <ricardo.neri-calderon@linux.intel.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Borislav Petkov <bp@suse.de>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Chen Yucong <slaoub@gmail.com>
Cc: Chris Metcalf <cmetcalf@mellanox.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Huang Rui <ray.huang@amd.com>
Cc: Jiri Slaby <jslaby@suse.cz>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Michael S. Tsirkin <mst@redhat.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Paul Gortmaker <paul.gortmaker@windriver.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ravi V. Shankar <ravi.v.shankar@intel.com>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: ricardo.neri@intel.com
Link: http://lkml.kernel.org/r/1509935277-22138-7-git-send-email-ricardo.neri-calderon@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Ingo Molnar [Fri, 1 Dec 2017 09:34:04 +0000 (10:34 +0100)]
Merge commit 'upstream-x86-virt' into WIP.x86/mm
Merge a minimal set of virt cleanups, for a base for the MM isolation patches.
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Ingo Molnar [Sun, 17 Dec 2017 12:09:31 +0000 (13:09 +0100)]
Merge branch 'upstream-acpi-fixes' into WIP.x86/pti.base
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Ingo Molnar [Sun, 17 Dec 2017 12:04:28 +0000 (13:04 +0100)]
Merge branch 'upstream-x86-selftests' into WIP.x86/pti.base
Conflicts:
arch/x86/kernel/cpu/Makefile
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Ingo Molnar [Fri, 1 Dec 2017 09:32:48 +0000 (10:32 +0100)]
Merge commit 'upstream-x86-entry' into WIP.x86/mm
Pull in a minimal set of v4.15 entry code changes, for a base for the MM isolation patches.
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Ingo Molnar [Tue, 5 Dec 2017 13:14:47 +0000 (14:14 +0100)]
drivers/misc/intel/pti: Rename the header file to free up the namespace
We'd like to use the 'PTI' acronym for 'Page Table Isolation' - free up the
namespace by renaming the <linux/pti.h> driver header to <linux/intel-pti.h>.
(Also standardize the header guard name while at it.)
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: J Freyensee <james_p_freyensee@linux.intel.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Linus Torvalds [Sun, 12 Nov 2017 18:46:13 +0000 (10:46 -0800)]
Linux 4.14
Linus Torvalds [Sun, 12 Nov 2017 18:12:41 +0000 (10:12 -0800)]
Merge branch 'x86-urgent-for-linus' of git://git./linux/kernel/git/tip/tip
Pull x86 fixes from Thomas Gleixner:
"A set of small fixes:
- make KGDB work again which got broken by the conversion of WARN()
to #UD. The WARN fixup needs to run before the notifier callchain,
otherwise KGDB tries to handle it and crashes.
- disable KASAN in the ORC unwinder to prevent false positive KASAN
warnings
- prevent default mapping above 47bit when 5 level page tables are
enabled
- make the delay calibration optimization work correctly, which had
the conditionals the wrong way around and was operating on data
which was not yet updated.
- remove the bogus X86_TRAP_BP trap init from the default IDT init
table, which broke 32bit int3 handling by overwriting the correct
int3 setup.
- replace this_cpu* with boot_cpu_data access in the preemptible
oprofile init code"
* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/debug: Handle warnings before the notifier chain, to fix KGDB crash
x86/mm: Fix ELF_ET_DYN_BASE for 5-level paging
x86/idt: Remove X86_TRAP_BP initialization in idt_setup_traps()
x86/oprofile/ppro: Do not use __this_cpu*() in preemptible context
x86/unwind: Disable KASAN checking in the ORC unwinder
x86/smpboot: Make optimization of delay calibration work correctly
Linus Torvalds [Sun, 12 Nov 2017 17:43:53 +0000 (09:43 -0800)]
Merge branch 'perf-urgent-for-linus' of git://git./linux/kernel/git/tip/tip
Pull perf tool fixes from Thomas Gleixner:
"A small set of fixes for perf tool:
- synchronize the i915 drm header to avoid the 'out of date' warning
- make sure that perf trace cleans up its temporary files on exit
- unbreak the build with newer flex versions
- add missing braces in the eBPF parsing rules"
* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
tooling/headers: Sync the tools/include/uapi/drm/i915_drm.h UAPI header
perf trace: Call machine__exit() at exit
perf tools: Fix eBPF event specification parsing
perf tools: Add "reject" option for parse-events.l
Linus Torvalds [Sat, 11 Nov 2017 17:10:39 +0000 (09:10 -0800)]
Merge git://git./linux/kernel/git/davem/net
Pull networking fixes from David Miller:
1) Use after free in vlan, from Cong Wang.
2) Handle NAPI poll with a zero budget properly in mlx5 driver, from
Saeed Mahameed.
3) If DMA mapping fails in mlx5 driver, NULL out page, from Inbar
Karmy.
4) Handle overrun in RX FIFO of sun4i CAN driver, from Gerhard
Bertelsmann.
5) Missing return in mdb and vlan prepare phase of DSA layer, from
Vivien Didelot.
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net:
vlan: fix a use-after-free in vlan_device_event()
net: dsa: return after vlan prepare phase
net: dsa: return after mdb prepare phase
can: ifi: Fix transmitter delay calculation
tcp: fix tcp_fastretrans_alert warning
tcp: gso: avoid refcount_t warning from tcp_gso_segment()
can: peak: Add support for new PCIe/M2 CAN FD interfaces
can: sun4i: handle overrun in RX FIFO
can: c_can: don't indicate triple sampling support for D_CAN
net/mlx5e: Increase Striding RQ minimum size limit to 4 multi-packet WQEs
net/mlx5e: Set page to null in case dma mapping fails
net/mlx5e: Fix napi poll with zero budget
net/mlx5: Cancel health poll before sending panic teardown command
net/mlx5: Loop over temp list to release delay events
rds: ib: Fix NULL pointer dereference in debug code
David S. Miller [Sat, 11 Nov 2017 12:52:01 +0000 (21:52 +0900)]
Merge tag 'linux-can-fixes-for-4.14-
20171110' of git://git./linux/kernel/git/mkl/linux-can
Marc Kleine-Budde says:
====================
pull-request: can 2017-11-10
this is a pull request for net/master.
The first patch by Richard Schütz for the c_can driver removes the false
indication to support triple sampling for d_can. Gerhard Bertelsmann's
patch for the sun4i driver improves the RX overrun handling. The patch
by Stephane Grosjean for the peak_canfd driver adds the PCI ids for
various new PCIe/M2 interfaces. Marek Vasut's patch for the ifi driver
fix transmitter delay calculation.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
David S. Miller [Sat, 11 Nov 2017 10:40:05 +0000 (19:40 +0900)]
Merge tag 'mlx5-fixes-2017-11-08' of git://git./linux/kernel/git/saeed/linux
Saeed Mahameed says:
====================
Mellanox, mlx5 fixes 2017-11-08
The following series includes some fixes for mlx5 core and etherent
driver.
Sorry for the late submission but as you can see i have some very
critical fixes below that i would like them merged into this RC.
Please pull and let me know if there is any problem.
For -stable:
('net/mlx5e: Set page to null in case dma mapping fails') kernels >= 4.13
('net/mlx5: FPGA, return -EINVAL if size is zero') kernels >= 4.13
('net/mlx5: Cancel health poll before sending panic teardown command') kernels >= 4.13
V1->V2:
- Fix Reviewed-by tag of the 2nd patch.
- Drop the FPGA 0 size fix, it needs some more change log info.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Cong Wang [Fri, 10 Nov 2017 00:43:13 +0000 (16:43 -0800)]
vlan: fix a use-after-free in vlan_device_event()
After refcnt reaches zero, vlan_vid_del() could free
dev->vlan_info via RCU:
RCU_INIT_POINTER(dev->vlan_info, NULL);
call_rcu(&vlan_info->rcu, vlan_info_rcu_free);
However, the pointer 'grp' still points to that memory
since it is set before vlan_vid_del():
vlan_info = rtnl_dereference(dev->vlan_info);
if (!vlan_info)
goto out;
grp = &vlan_info->grp;
Depends on when that RCU callback is scheduled, we could
trigger a use-after-free in vlan_group_for_each_dev()
right following this vlan_vid_del().
Fix it by moving vlan_vid_del() before setting grp. This
is also symmetric to the vlan_vid_add() we call in
vlan_device_event().
Reported-by: Fengguang Wu <fengguang.wu@intel.com>
Fixes: efc73f4bbc23 ("net: Fix memory leak - vlan_info struct")
Cc: Alexander Duyck <alexander.duyck@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Girish Moodalbail <girish.moodalbail@oracle.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Reviewed-by: Girish Moodalbail <girish.moodalbail@oracle.com>
Tested-by: Fengguang Wu <fengguang.wu@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Ingo Molnar [Sat, 11 Nov 2017 08:06:57 +0000 (09:06 +0100)]
tooling/headers: Sync the tools/include/uapi/drm/i915_drm.h UAPI header
Last minute upstream update to one of the UAPI headers - sync it with tooling,
to address this warning:
Warning: Kernel ABI header at 'tools/include/uapi/drm/i915_drm.h' differs from latest version at 'include/uapi/drm/i915_drm.h'
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Ingo Molnar [Sat, 11 Nov 2017 08:03:59 +0000 (09:03 +0100)]
Merge branch 'perf/urgent' of git://git./linux/kernel/git/acme/linux into perf/urgent
Pull perf tooling fixes from Arnaldo Carvalho de Melo.
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Vivien Didelot [Wed, 8 Nov 2017 15:50:10 +0000 (10:50 -0500)]
net: dsa: return after vlan prepare phase
The current code does not return after successfully preparing the VLAN
addition on every ports member of a it. Fix this.
Fixes: 1ca4aa9cd4cc ("net: dsa: check VLAN capability of every switch")
Signed-off-by: Vivien Didelot <vivien.didelot@savoirfairelinux.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
Vivien Didelot [Wed, 8 Nov 2017 15:49:56 +0000 (10:49 -0500)]
net: dsa: return after mdb prepare phase
The current code does not return after successfully preparing the MDB
addition on every ports member of a multicast group. Fix this.
Fixes: a1a6b7ea7f2d ("net: dsa: add cross-chip multicast support")
Reported-by: Egil Hjelmeland <privat@egil-hjelmeland.no>
Signed-off-by: Vivien Didelot <vivien.didelot@savoirfairelinux.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
Linus Torvalds [Fri, 10 Nov 2017 22:18:24 +0000 (14:18 -0800)]
Merge tag 'ceph-for-4.14-rc9' of git://github.com/ceph/ceph-client
Pull ceph gix from Ilya Dryomov:
"Memory allocation flags fix, marked for stable"
* tag 'ceph-for-4.14-rc9' of git://github.com/ceph/ceph-client:
rbd: use GFP_NOIO for parent stat and data requests
Linus Torvalds [Fri, 10 Nov 2017 22:14:23 +0000 (14:14 -0800)]
Merge branch 'for-linus' of git://git./linux/kernel/git/dtor/input
Pull input layer updates from Dmitry Torokhov:
- a new ACPI ID for Elan touchpad found in yet another Ideapad model
- Synaptics RMI4 will allow binding to controllers reporting SMB
version 3 (note that we are not adding any new ACPI IDs to the
Synaptics PS/2 drover so unless user explicitly enables intertouch
support there is no user-visible change)
- a fixup to TSC 2004/5 touchscreen driver to mark input devices as
"direct" to help userspace identify the type of device they are
dealing with
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input:
Input: synaptics-rmi4 - RMI4 can also use SMBUS version 3
Input: tsc200x-core - set INPUT_PROP_DIRECT
Input: elan_i2c - add ELAN060C to the ACPI table
Linus Torvalds [Fri, 10 Nov 2017 20:24:42 +0000 (12:24 -0800)]
Merge tag 'for-linus' of git://git./virt/kvm/kvm
Pull KVM fix from Radim Krčmář:
"Fix PPC HV host crash that can occur as a result of resizing the guest
hashed page table"
* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
KVM: PPC: Book3S HV: Fix exclusion between HPT resizing and other HPT updates
Linus Torvalds [Fri, 10 Nov 2017 20:21:15 +0000 (12:21 -0800)]
Merge tag 'mips_fixes_4.14_2' of git://git./linux/kernel/git/jhogan/mips
Pull MIPS fixes from James Hogan:
"A final few MIPS fixes for 4.14:
- fix BMIPS NULL pointer dereference (4.7)
- fix AR7 early GPIO init allocation failure (3.19)
- fix dead serial output on certain AR7 platforms (2.6.35)"
* tag 'mips_fixes_4.14_2' of git://git.kernel.org/pub/scm/linux/kernel/git/jhogan/mips:
MIPS: AR7: Ensure that serial ports are properly set up
MIPS: AR7: Defer registration of GPIO
MIPS: BMIPS: Fix missing cbr address
Maciej W. Rozycki [Fri, 10 Nov 2017 20:05:24 +0000 (20:05 +0000)]
.mailmap: Add Maciej W. Rozycki's Imagination e-mail address
Following my recent transition from Imagination Technologies to the=20
reincarnated MIPS company add a .mailmap mapping for my work address,
so that `scripts/get_maintainer.pl' gets it right for past commits.
Signed-off-by: Maciej W. Rozycki <macro@mips.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Linus Torvalds [Fri, 10 Nov 2017 19:19:11 +0000 (11:19 -0800)]
Revert "x86: CPU: Fix up "cpu MHz" in /proc/cpuinfo"
This reverts commit
941f5f0f6ef5338814145cf2b813cf1f98873e2f.
Sadly, it turns out that we really can't just do the cross-CPU IPI to
all CPU's to get their proper frequencies, because it's much too
expensive on systems with lots of cores.
So we'll have to revert this for now, and revisit it using a smarter
model (probably doing one system-wide IPI at open time, and doing all
the frequency calculations in parallel).
Reported-by: WANG Chao <chao.wang@ucloud.cn>
Reported-by: Ingo Molnar <mingo@kernel.org>
Cc: Rafael J Wysocki <rafael.j.wysocki@intel.com>
Cc: stable@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Linus Torvalds [Fri, 10 Nov 2017 17:59:41 +0000 (09:59 -0800)]
Merge tag 'drm-fixes-for-v4.14-rc9' of git://people.freedesktop.org/~airlied/linux
Pull drm fixes from Dave Airlie:
"Last few patches to wrap up.
Two i915 fixes that are on their way to stable, one vmware black
screen bug, and one const patch that I was going to drop, but it was
clearly a pretty safe one liner"
* tag 'drm-fixes-for-v4.14-rc9' of git://people.freedesktop.org/~airlied/linux:
drm/i915: Deconstruct struct sgt_dma initialiser
drm/i915: Reject unknown syncobj flags
drm/vmwgfx: Fix Ubuntu 17.10 Wayland black screen issue
drm/vmwgfx: constify vmw_fence_ops
Marek Vasut [Fri, 10 Nov 2017 10:22:39 +0000 (11:22 +0100)]
can: ifi: Fix transmitter delay calculation
The CANFD transmitter delay calculation formula was updated in the
latest software drop from IFI and improves the behavior of the IFI
CANFD core during bitrate switching. Use the new formula to improve
stability of the CANFD operation.
Signed-off-by: Marek Vasut <marex@denx.de>
Cc: Markus Marb <markus@marb.org>
Cc: linux-stable <stable@vger.kernel.org>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Yuchung Cheng [Tue, 7 Nov 2017 23:33:43 +0000 (15:33 -0800)]
tcp: fix tcp_fastretrans_alert warning
This patch fixes the cause of an WARNING indicatng TCP has pending
retransmission in Open state in tcp_fastretrans_alert().
The root cause is a bad interaction between path mtu probing,
if enabled, and the RACK loss detection. Upong receiving a SACK
above the sequence of the MTU probing packet, RACK could mark the
probe packet lost in tcp_fastretrans_alert(), prior to calling
tcp_simple_retransmit().
tcp_simple_retransmit() only enters Loss state if it newly marks
the probe packet lost. If the probe packet is already identified as
lost by RACK, the sender remains in Open state with some packets
marked lost and retransmitted. Then the next SACK would trigger
the warning. The likely scenario is that the probe packet was
lost due to its size or network congestion. The actual impact of
this warning is small by potentially entering fast recovery an
ACK later.
The simple fix is always entering recovery (Loss) state if some
packet is marked lost during path MTU probing.
Fixes: a0370b3f3f2c ("tcp: enable RACK loss detection to trigger recovery")
Reported-by: Oleksandr Natalenko <oleksandr@natalenko.name>
Reported-by: Alexei Starovoitov <alexei.starovoitov@gmail.com>
Reported-by: Roman Gushchin <guro@fb.com>
Signed-off-by: Yuchung Cheng <ycheng@google.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Acked-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Eric Dumazet [Tue, 7 Nov 2017 23:15:04 +0000 (15:15 -0800)]
tcp: gso: avoid refcount_t warning from tcp_gso_segment()
When a GSO skb of truesize O is segmented into 2 new skbs of truesize N1
and N2, we want to transfer socket ownership to the new fresh skbs.
In order to avoid expensive atomic operations on a cache line subject to
cache bouncing, we replace the sequence :
refcount_add(N1, &sk->sk_wmem_alloc);
refcount_add(N2, &sk->sk_wmem_alloc); // repeated by number of segments
refcount_sub(O, &sk->sk_wmem_alloc);
by a single
refcount_add(sum_of(N) - O, &sk->sk_wmem_alloc);
Problem is :
In some pathological cases, sum(N) - O might be a negative number, and
syzkaller bot was apparently able to trigger this trace [1]
atomic_t was ok with this construct, but we need to take care of the
negative delta with refcount_t
[1]
refcount_t: saturated; leaking memory.
------------[ cut here ]------------
WARNING: CPU: 0 PID: 8404 at lib/refcount.c:77 refcount_add_not_zero+0x198/0x200 lib/refcount.c:77
Kernel panic - not syncing: panic_on_warn set ...
CPU: 0 PID: 8404 Comm: syz-executor2 Not tainted 4.14.0-rc5-mm1+ #20
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
__dump_stack lib/dump_stack.c:16 [inline]
dump_stack+0x194/0x257 lib/dump_stack.c:52
panic+0x1e4/0x41c kernel/panic.c:183
__warn+0x1c4/0x1e0 kernel/panic.c:546
report_bug+0x211/0x2d0 lib/bug.c:183
fixup_bug+0x40/0x90 arch/x86/kernel/traps.c:177
do_trap_no_signal arch/x86/kernel/traps.c:211 [inline]
do_trap+0x260/0x390 arch/x86/kernel/traps.c:260
do_error_trap+0x120/0x390 arch/x86/kernel/traps.c:297
do_invalid_op+0x1b/0x20 arch/x86/kernel/traps.c:310
invalid_op+0x18/0x20 arch/x86/entry/entry_64.S:905
RIP: 0010:refcount_add_not_zero+0x198/0x200 lib/refcount.c:77
RSP: 0018:
ffff8801c606e3a0 EFLAGS:
00010282
RAX:
0000000000000026 RBX:
0000000000001401 RCX:
0000000000000000
RDX:
0000000000000026 RSI:
ffffc900036fc000 RDI:
ffffed0038c0dc68
RBP:
ffff8801c606e430 R08:
0000000000000001 R09:
0000000000000000
R10:
ffff8801d97f5eba R11:
0000000000000000 R12:
ffff8801d5acf73c
R13:
1ffff10038c0dc75 R14:
00000000ffffffff R15:
00000000fffff72f
refcount_add+0x1b/0x60 lib/refcount.c:101
tcp_gso_segment+0x10d0/0x16b0 net/ipv4/tcp_offload.c:155
tcp4_gso_segment+0xd4/0x310 net/ipv4/tcp_offload.c:51
inet_gso_segment+0x60c/0x11c0 net/ipv4/af_inet.c:1271
skb_mac_gso_segment+0x33f/0x660 net/core/dev.c:2749
__skb_gso_segment+0x35f/0x7f0 net/core/dev.c:2821
skb_gso_segment include/linux/netdevice.h:3971 [inline]
validate_xmit_skb+0x4ba/0xb20 net/core/dev.c:3074
__dev_queue_xmit+0xe49/0x2070 net/core/dev.c:3497
dev_queue_xmit+0x17/0x20 net/core/dev.c:3538
neigh_hh_output include/net/neighbour.h:471 [inline]
neigh_output include/net/neighbour.h:479 [inline]
ip_finish_output2+0xece/0x1460 net/ipv4/ip_output.c:229
ip_finish_output+0x85e/0xd10 net/ipv4/ip_output.c:317
NF_HOOK_COND include/linux/netfilter.h:238 [inline]
ip_output+0x1cc/0x860 net/ipv4/ip_output.c:405
dst_output include/net/dst.h:459 [inline]
ip_local_out+0x95/0x160 net/ipv4/ip_output.c:124
ip_queue_xmit+0x8c6/0x18e0 net/ipv4/ip_output.c:504
tcp_transmit_skb+0x1ab7/0x3840 net/ipv4/tcp_output.c:1137
tcp_write_xmit+0x663/0x4de0 net/ipv4/tcp_output.c:2341
__tcp_push_pending_frames+0xa0/0x250 net/ipv4/tcp_output.c:2513
tcp_push_pending_frames include/net/tcp.h:1722 [inline]
tcp_data_snd_check net/ipv4/tcp_input.c:5050 [inline]
tcp_rcv_established+0x8c7/0x18a0 net/ipv4/tcp_input.c:5497
tcp_v4_do_rcv+0x2ab/0x7d0 net/ipv4/tcp_ipv4.c:1460
sk_backlog_rcv include/net/sock.h:909 [inline]
__release_sock+0x124/0x360 net/core/sock.c:2264
release_sock+0xa4/0x2a0 net/core/sock.c:2776
tcp_sendmsg+0x3a/0x50 net/ipv4/tcp.c:1462
inet_sendmsg+0x11f/0x5e0 net/ipv4/af_inet.c:763
sock_sendmsg_nosec net/socket.c:632 [inline]
sock_sendmsg+0xca/0x110 net/socket.c:642
___sys_sendmsg+0x31c/0x890 net/socket.c:2048
__sys_sendmmsg+0x1e6/0x5f0 net/socket.c:2138
Fixes: 14afee4b6092 ("net: convert sock.sk_wmem_alloc from atomic_t to refcount_t")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Juergen Gross [Thu, 9 Nov 2017 13:27:36 +0000 (14:27 +0100)]
x86/virt: Add enum for hypervisors to replace x86_hyper
The x86_hyper pointer is only used for checking whether a virtual
device is supporting the hypervisor the system is running on.
Use an enum for that purpose instead and drop the x86_hyper pointer.
Signed-off-by: Juergen Gross <jgross@suse.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Xavier Deguillard <xdeguillard@vmware.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: akataria@vmware.com
Cc: arnd@arndb.de
Cc: boris.ostrovsky@oracle.com
Cc: devel@linuxdriverproject.org
Cc: dmitry.torokhov@gmail.com
Cc: gregkh@linuxfoundation.org
Cc: haiyangz@microsoft.com
Cc: kvm@vger.kernel.org
Cc: kys@microsoft.com
Cc: linux-graphics-maintainer@vmware.com
Cc: linux-input@vger.kernel.org
Cc: moltmann@vmware.com
Cc: pbonzini@redhat.com
Cc: pv-drivers@vmware.com
Cc: rkrcmar@redhat.com
Cc: sthemmin@microsoft.com
Cc: virtualization@lists.linux-foundation.org
Cc: xen-devel@lists.xenproject.org
Link: http://lkml.kernel.org/r/20171109132739.23465-3-jgross@suse.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Juergen Gross [Thu, 9 Nov 2017 13:27:35 +0000 (14:27 +0100)]
x86/virt, x86/platform: Merge 'struct x86_hyper' into 'struct x86_platform' and 'struct x86_init'
Instead of x86_hyper being either NULL on bare metal or a pointer to a
struct hypervisor_x86 in case of the kernel running as a guest merge
the struct into x86_platform and x86_init.
This will remove the need for wrappers making it hard to find out what
is being called. With dummy functions added for all callbacks testing
for a NULL function pointer can be removed, too.
Suggested-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Juergen Gross <jgross@suse.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: akataria@vmware.com
Cc: boris.ostrovsky@oracle.com
Cc: devel@linuxdriverproject.org
Cc: haiyangz@microsoft.com
Cc: kvm@vger.kernel.org
Cc: kys@microsoft.com
Cc: pbonzini@redhat.com
Cc: rkrcmar@redhat.com
Cc: rusty@rustcorp.com.au
Cc: sthemmin@microsoft.com
Cc: virtualization@lists.linux-foundation.org
Cc: xen-devel@lists.xenproject.org
Link: http://lkml.kernel.org/r/20171109132739.23465-2-jgross@suse.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
projects / openwrt / staging / blogic.git / log