linux-toradex.git/arch, branch v4.14-rc3

Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

2017-10-01T20:55:32+00:00

Pull x86 fixes from Thomas Gleixner:
 "This contains the following fixes and improvements:

   - Avoid dereferencing an unprotected VMA pointer in the fault signal
     generation code

   - Fix inline asm call constraints for GCC 4.4

   - Use existing register variable to retrieve the stack pointer
     instead of forcing the compiler to create another indirect access
     which results in excessive extra 'mov %rsp, %' instructions

   - Disable branch profiling for the memory encryption code to prevent
     an early boot crash

   - Fix a sparse warning caused by casting the __user annotation in
     __get_user_asm_u64() away

   - Fix an off by one error in the loop termination of the error patch
     in the x86 sysfs init code

   - Add missing CPU IDs to various Intel specific drivers to enable the
     functionality on recent hardware

   - More (init) constification in the numachip code"

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/asm: Use register variable to get stack pointer value
  x86/mm: Disable branch profiling in mem_encrypt.c
  x86/asm: Fix inline asm call constraints for GCC 4.4
  perf/x86/intel/uncore: Correct num_boxes for IIO and IRP
  perf/x86/intel/rapl: Add missing CPU IDs
  perf/x86/msr: Add missing CPU IDs
  perf/x86/intel/cstate: Add missing CPU IDs
  x86: Don't cast away the __user in __get_user_asm_u64()
  x86/sysfs: Fix off-by-one error in loop termination
  x86/mm: Fix fault error path using unsafe vma pointer
  x86/numachip: Add const and __initconst to numachip2_clockevent

Merge branch 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

2017-10-01T20:03:16+00:00

Pull timer fixes from Thomas Gleixner:
 "This adds a new timer wheel function which is required for the
  conversion of the timer callback function from the 'unsigned long
  data' argument to 'struct timer_list *timer'. This conversion has two
  benefits:

   1) It makes struct timer_list smaller

   2) Many callers hand in a pointer to the timer or to the structure
      containing the timer, which happens via type casting both at setup
      and in the callback. This change gets rid of the typecasts.

  Once the conversion is complete, which is planned for 4.15, the old
  setup function and the intermediate typecast in the new setup function
  go away along with the data field in struct timer_list.

  Merging this now into mainline allows a smooth queueing of the actual
  conversion in the affected maintainer trees without creating
  dependencies"

* 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  um/time: Fixup namespace collision
  timer: Prepare to change timer callback argument type

Merge tag 'led_fixes-4.14-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/j.anaszewski/linux-leds

2017-09-30T02:33:32+00:00

Pull LED fixes from Jacek Anaszewski:
 "Four fixes for the as3645a LED flash controller and one update to
  MAINTAINERS"

* tag 'led_fixes-4.14-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/j.anaszewski/linux-leds:
  MAINTAINERS: Add entry for MediaTek PMIC LED driver
  as3645a: Unregister indicator LED on device unbind
  as3645a: Use integer numbers for parsing LEDs
  dt: bindings: as3645a: Use LED number to refer to LEDs
  as3645a: Use ams,input-max-microamp as documented in DT bindings

Merge tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux

2017-09-29T19:31:35+00:00

Pull arm64 fixes from Catalin Marinas:

 - SPsel register initialisation on reset as the architecture defines
   its state as unknown

 - Use READ_ONCE when dereferencing pmd_t pointers to avoid race
   conditions in page_vma_mapped_walk() (or fast GUP) with concurrent
   modifications of the page table

 - Avoid invoking the mm fault handling code for kernel addresses (check
   against TASK_SIZE) which would otherwise result in calling
   might_sleep() in atomic context

* tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux:
  arm64: fault: Route pte translation faults via do_translation_fault
  arm64: mm: Use READ_ONCE when dereferencing pointer to pte table
  arm64: Make sure SPsel is always set

Merge tag 'for-linus-4.14c-rc3-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip

2017-09-29T19:24:28+00:00

Pull xen fixes from Juergen Gross:

 - avoid a warning when compiling with clang

 - consider read-only bits in xen-pciback when writing to a BAR

 - fix a boot crash of pv-domains

* tag 'for-linus-4.14c-rc3-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
  xen/mmu: Call xen_cleanhighmap() with 4MB aligned for page tables mapping
  xen-pciback: relax BAR sizing write value check
  x86/xen: clean up clang build warning

Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm

2017-09-29T19:18:55+00:00

Pull kvm fixes from Paolo Bonzini:
 "Mixed bugfixes. Perhaps the most interesting one is a latent bug that
  was finally triggered by PCID support"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
  kvm/x86: Handle async PF in RCU read-side critical sections
  KVM: nVMX: Fix nested #PF intends to break L1's vmlauch/vmresume
  KVM: VMX: use cmpxchg64
  KVM: VMX: simplify and fix vmx_vcpu_pi_load
  KVM: VMX: avoid double list add with VT-d posted interrupts
  KVM: VMX: extract __pi_post_block
  KVM: PPC: Book3S HV: Check for updated HDSISR on P9 HDSI exception
  KVM: nVMX: fix HOST_CR3/HOST_CR4 cache

x86/asm: Use register variable to get stack pointer value

2017-09-29T17:39:44+00:00

Currently we use current_stack_pointer() function to get the value
of the stack pointer register. Since commit:

  f5caf621ee35 ("x86/asm: Fix inline asm call constraints for Clang")

... we have a stack register variable declared. It can be used instead of
current_stack_pointer() function which allows to optimize away some
excessive "mov %rsp, %" instructions:

 -mov    %rsp,%rdx
 -sub    %rdx,%rax
 -cmp    $0x3fff,%rax
 -ja     ffffffff810722fd 

 +sub    %rsp,%rax
 +cmp    $0x3fff,%rax
 +ja     ffffffff810722fa 

Remove current_stack_pointer(), rename __asm_call_sp to current_stack_pointer
and use it instead of the removed function.

Signed-off-by: Andrey Ryabinin 
Reviewed-by: Josh Poimboeuf 
Cc: Andy Lutomirski 
Cc: Linus Torvalds 
Cc: Peter Zijlstra 
Cc: Thomas Gleixner 
Link: http://lkml.kernel.org/r/20170929141537.29167-1-aryabinin@virtuozzo.com
Signed-off-by: Ingo Molnar

x86/mm: Disable branch profiling in mem_encrypt.c

2017-09-29T17:37:51+00:00

Some routines in mem_encrypt.c are called very early in the boot process,
e.g. sme_encrypt_kernel(). When CONFIG_TRACE_BRANCH_PROFILING=y is defined
the resulting branch profiling associated with the check to see if SME is
active results in a kernel crash. Disable branch profiling for
mem_encrypt.c by defining DISABLE_BRANCH_PROFILING before including any
header files.

Reported-by: kernel test robot 
Signed-off-by: Tom Lendacky 
Acked-by: Borislav Petkov 
Cc: Borislav Petkov 
Cc: Linus Torvalds 
Cc: Peter Zijlstra 
Cc: Thomas Gleixner 
Link: http://lkml.kernel.org/r/20170929162419.6016.53390.stgit@tlendack-t1.amdoffice.net
Signed-off-by: Ingo Molnar

arm64: fault: Route pte translation faults via do_translation_fault

2017-09-29T15:47:40+00:00

We currently route pte translation faults via do_page_fault, which elides
the address check against TASK_SIZE before invoking the mm fault handling
code. However, this can cause issues with the path walking code in
conjunction with our word-at-a-time implementation because
load_unaligned_zeropad can end up faulting in kernel space if it reads
across a page boundary and runs into a page fault (e.g. by attempting to
read from a guard region).

In the case of such a fault, load_unaligned_zeropad has registered a
fixup to shift the valid data and pad with zeroes, however the abort is
reported as a level 3 translation fault and we dispatch it straight to
do_page_fault, despite it being a kernel address. This results in calling
a sleeping function from atomic context:

  BUG: sleeping function called from invalid context at arch/arm64/mm/fault.c:313
  in_atomic(): 0, irqs_disabled(): 0, pid: 10290
  Internal error: Oops - BUG: 0 [#1] PREEMPT SMP
  [...]
  [] ___might_sleep+0x134/0x144
  [] __might_sleep+0x7c/0x8c
  [] do_page_fault+0x140/0x330
  [] do_mem_abort+0x54/0xb0
  Exception stack(0xfffffffb20247a70 to 0xfffffffb20247ba0)
  [...]
  [] el1_da+0x18/0x78
  [] path_parentat+0x44/0x88
  [] filename_parentat+0x5c/0xd8
  [] filename_create+0x4c/0x128
  [] SyS_mkdirat+0x50/0xc8
  [] el0_svc_naked+0x24/0x28
  Code: 36380080 d5384100 f9400800 9402566d (d4210000)
  ---[ end trace 2d01889f2bca9b9f ]---

Fix this by dispatching all translation faults to do_translation_faults,
which avoids invoking the page fault logic for faults on kernel addresses.

Cc: 
Reported-by: Ankit Jain 
Signed-off-by: Will Deacon 
Signed-off-by: Catalin Marinas

arm64: mm: Use READ_ONCE when dereferencing pointer to pte table

2017-09-29T15:46:43+00:00

On kernels built with support for transparent huge pages, different CPUs
can access the PMD concurrently due to e.g. fast GUP or page_vma_mapped_walk
and they must take care to use READ_ONCE to avoid value tearing or caching
of stale values by the compiler. Unfortunately, these functions call into
our pgtable macros, which don't use READ_ONCE, and compiler caching has
been observed to cause the following crash during ext4 writeback:

PC is at check_pte+0x20/0x170
LR is at page_vma_mapped_walk+0x2e0/0x540
[...]
Process doio (pid: 2463, stack limit = 0xffff00000f2e8000)
Call trace:
[] check_pte+0x20/0x170
[] page_vma_mapped_walk+0x2e0/0x540
[] page_mkclean_one+0xac/0x278
[] rmap_walk_file+0xf0/0x238
[] rmap_walk+0x64/0xa0
[] page_mkclean+0x90/0xa8
[] clear_page_dirty_for_io+0x84/0x2a8
[] mpage_submit_page+0x34/0x98
[] mpage_process_page_bufs+0x164/0x170
[] mpage_prepare_extent_to_map+0x134/0x2b8
[] ext4_writepages+0x484/0xe30
[] do_writepages+0x44/0xe8
[] __filemap_fdatawrite_range+0xbc/0x110
[] file_write_and_wait_range+0x48/0xd8
[] ext4_sync_file+0x80/0x4b8
[] vfs_fsync_range+0x64/0xc0
[] SyS_msync+0x194/0x1e8

This is because page_vma_mapped_walk loads the PMD twice before calling
pte_offset_map: the first time without READ_ONCE (where it gets all zeroes
due to a concurrent pmdp_invalidate) and the second time with READ_ONCE
(where it sees a valid table pointer due to a concurrent pmd_populate).
However, the compiler inlines everything and caches the first value in
a register, which is subsequently used in pte_offset_phys which returns
a junk pointer that is later dereferenced when attempting to access the
relevant pte.

This patch fixes the issue by using READ_ONCE in pte_offset_phys to ensure
that a stale value is not used. Whilst this is a point fix for a known
failure (and simple to backport), a full fix moving all of our page table
accessors over to {READ,WRITE}_ONCE and consistently using READ_ONCE in
page_vma_mapped_walk is in the works for a future kernel release.

Cc: Jon Masters 
Cc: Timur Tabi 
Cc: 
Fixes: f27176cfc363 ("mm: convert page_mkclean_one() to use page_vma_mapped_walk()")
Tested-by: Richard Ruigrok 
Signed-off-by: Will Deacon 
Signed-off-by: Catalin Marinas