Skip to content

L
linux
Switch branch/tag
  1. 16 May, 2014 15 commits
  3. 30 Apr, 2014 18 commits
  5. 28 Apr, 2014 1 commit
  7. 27 Apr, 2014 6 commits
    • Will Deacon's avatar
      word-at-a-time: avoid undefined behaviour in zero_bytemask macro · ec6931b2
      Will Deacon authored 
      The asm-generic, big-endian version of zero_bytemask creates a mask of
bytes preceding the first zero-byte by left shifting ~0ul based on the
position of the first zero byte.

Unfortunately, if the first (top) byte is zero, the output of
prep_zero_mask has only the top bit set, resulting in undefined C
behaviour as we shift left by an amount equal to the width of the type.
As it happens, GCC doesn't manage to spot this through the call to fls(),
but the issue remains if architectures choose to implement their shift
instructions differently.

An example would be arch/arm/ (AArch32), where LSL Rd, Rn, #32 results
in Rd == 0x0, whilst on arch/arm64 (AArch64) LSL Xd, Xn, #64 results in
Xd == Xn.

Rather than check explicitly for the problematic shift, this patch adds
an extra shift by 1, replacing fls with __fls. Since zero_bytemask is
never called with a zero argument (has_zero() is used to check the data
first), we don't need to worry about calling __fls(0), which is
undefined.

Cc: <stable@vger.kernel.org>
Cc: Victor Kamensky <victor.kamensky@linaro.org>
Signed-off-by: default avatarWill Deacon <will.deacon@arm.com>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      ec6931b2
    • Linus Torvalds's avatar
      Merge branch 'safe-dirty-tlb-flush' · ac6c9e2b
      Linus Torvalds authored 
      This merges the patch to fix possible loss of dirty bit on munmap() or
madvice(DONTNEED).  If there are concurrent writers on other CPU's that
have the unmapped/unneeded page in their TLBs, their writes to the page
could possibly get lost if a third CPU raced with the TLB flush and did
a page_mkclean() before the page was fully written.

Admittedly, if you unmap() or madvice(DONTNEED) an area _while_ another
thread is still busy writing to it, you deserve all the lost writes you
could get.  But we kernel people hold ourselves to higher quality
standards than "crazy people deserve to lose", because, well, we've seen
people do all kinds of crazy things.

So let's get it right, just because we can, and we don't have to worry
about it.

* safe-dirty-tlb-flush:
  mm: split 'tlb_flush_mmu()' into tlb flushing and memory freeing parts
      ac6c9e2b
    • Linus Torvalds's avatar
      Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs · 33c0022f
      Linus Torvalds authored 
      Pull btrfs fixes from Chris Mason.

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs:
  Btrfs: limit the path size in send to PATH_MAX
  Btrfs: correctly set profile flags on seqlock retry
  Btrfs: use correct key when repeating search for extent item
  Btrfs: fix inode caching vs tree log
  Btrfs: fix possible memory leaks in open_ctree()
  Btrfs: avoid triggering bug_on() when we fail to start inode caching task
  Btrfs: move btrfs_{set,clear}_and_info() to ctree.h
  btrfs: replace error code from btrfs_drop_extents
  btrfs: Change the hole range to a more accurate value.
  btrfs: fix use-after-free in mount_subvol()
      33c0022f
    • Linus Torvalds's avatar
      Merge branch 'fixes' of git://ftp.arm.linux.org.uk/~rmk/linux-arm · 2b9d1c05
      Linus Torvalds authored 
      Pull arm fixes from Russell King:
 "A number of fixes for the PJ4/iwmmxt changes which arm-soc forced me
  to take during the merge window.  This stuff should have been better
  tested and sorted out *before* the merge window"

* 'fixes' of git://ftp.arm.linux.org.uk/~rmk/linux-arm:
  ARM: 8042/1: iwmmxt: allow to build iWMMXt on Marvell PJ4B
  ARM: 8041/1: pj4: fix cpu_is_pj4 check
  ARM: 8040/1: pj4: properly detect existence of iWMMXt coprocessor
  ARM: 8039/1: pj4: enable iWMMXt only if CONFIG_IWMMXT is set
  ARM: 8038/1: iwmmxt: explicitly check for supported architectures
      2b9d1c05
    • Linus Torvalds's avatar
      Merge tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux · afa3cad7
      Linus Torvalds authored 
      Pull arm64 fixes from Catalin Marinas:
 - compat renameat2 syscall wiring and __NR_compat_syscalls fix
 - TLB fix for transparent huge pages following switch to generic
   mmu_gather
 - spinlock initialisation for init_mm's context
 - move of_clk_init() earlier
 - Kconfig duplicate entry fix

* tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux:
  arm64: init: Move of_clk_init to time_init
  arm64: initialize spinlock for init_mm's context
  arm64: debug: remove noisy, pointless warning
  arm64: mm: Add THP TLB entries to general mmu_gather
  arm64: add renameat2 compat syscall
  ARM64: Remove duplicated Kconfig entry for "kernel/power/Kconfig"
  arm64: __NR_compat_syscalls fix
      afa3cad7
    • Linus Torvalds's avatar
      Merge branch 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip · d9e9e8e2
      Linus Torvalds authored 
      Pull irq fixes from Thomas Gleixner:
 "A slighlty large fix for a subtle issue in the CPU hotplug code of
  certain ARM SoCs, where the not yet online cpu needs to setup the cpu
  local timer and needs to set the interrupt affinity to itself.
  Setting interrupt affinity to a not online cpu is prohibited and
  therefor the timer interrupt ends up on the wrong cpu, which leads to
  nasty complications.

  The SoC folks tried to hack around that in the SoC code in some more
  than nasty ways.  The proper solution is to have a way to enforce the
  affinity setting to a not online cpu.  The core patch to the genirq
  code provides that facility and the follow up patches make use of it
  in the GIC interrupt controller and the exynos timer driver.

  The change to the core code has no implications to existing users,
  except for the rename of the locked function and therefor the
  necessary fixup in mips/cavium.  Aside of that, no runtime impact is
  possible, as none of the existing interrupt chips implements anything
  which depends on the force argument of the irq_set_affinity()
  callback"

* 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  clocksource: Exynos_mct: Register clock event after request_irq()
  clocksource: Exynos_mct: Use irq_force_affinity() in cpu bringup
  irqchip: Gic: Support forced affinity setting
  genirq: Allow forcing cpu affinity of interrupts
      d9e9e8e2
GitLab Nexedi Edition | About GitLab | About Nexedi | 沪ICP备2021021310号-2 | 沪ICP备2021021310号-7