Skip to content

cloud-kernel
cloud-kernel

openanolis / cloud-kernel
1 年多 前同步成功

通知 160
Star 36
Fork 7
cloud-kernel
cloud-kernel
切换分支/标签
  1. 05 6月, 2009 29 次提交
  3. 02 6月, 2009 1 次提交
  5. 30 5月, 2009 2 次提交
  7. 29 5月, 2009 5 次提交
    • M
      x86: ignore VM_LOCKED when determining if hugetlb-backed page tables can be shared or not · 32b154c0
      由 Mel Gorman 提交于 
      Addresses http://bugzilla.kernel.org/show_bug.cgi?id=13302

On x86 and x86-64, it is possible that page tables are shared beween
shared mappings backed by hugetlbfs.  As part of this,
page_table_shareable() checks a pair of vma->vm_flags and they must match
if they are to be shared.  All VMA flags are taken into account, including
VM_LOCKED.

The problem is that VM_LOCKED is cleared on fork().  When a process with a
shared memory segment forks() to exec() a helper, there will be shared
VMAs with different flags.  The impact is that the shared segment is
sometimes considered shareable and other times not, depending on what
process is checking.

What happens is that the segment page tables are being shared but the
count is inaccurate depending on the ordering of events.  As the page
tables are freed with put_page(), bad pmd's are found when some of the
children exit.  The hugepage counters also get corrupted and the Total and
Free count will no longer match even when all the hugepage-backed regions
are freed.  This requires a reboot of the machine to "fix".

This patch addresses the problem by comparing all flags except VM_LOCKED
when deciding if pagetables should be shared or not for hugetlbfs-backed
mapping.
Signed-off-by: NMel Gorman <mel@csn.ul.ie>
Acked-by: NHugh Dickins <hugh.dickins@tiscali.co.uk>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: <stable@kernel.org>
Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: <starlight@binnacle.cx>
Cc: Eric B Munson <ebmunson@us.ibm.com>
Cc: Adam Litke <agl@us.ibm.com>
Cc: Andy Whitcroft <apw@canonical.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      32b154c0
    • O
      flat: fix data sections alignment · c3dc5bec
      由 Oskar Schirmer 提交于 
      The flat loader uses an architecture's flat_stack_align() to align the
stack but assumes word-alignment is enough for the data sections.

However, on the Xtensa S6000 we have registers up to 128bit width
which can be used from userspace and therefor need userspace stack and
data-section alignment of at least this size.

This patch drops flat_stack_align() and uses the same alignment that
is required for slab caches, ARCH_SLAB_MINALIGN, or wordsize if it's
not defined by the architecture.

It also fixes m32r which was obviously kaput, aligning an
uninitialized stack entry instead of the stack pointer.

[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: NOskar Schirmer <os@emlix.com>
Cc: David Howells <dhowells@redhat.com>
Cc: Russell King <rmk@arm.linux.org.uk>
Cc: Bryan Wu <cooloney@kernel.org>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: NPaul Mundt <lethal@linux-sh.org>
Cc: Greg Ungerer <gerg@uclinux.org>
Signed-off-by: NJohannes Weiner <jw@emlix.com>
Acked-by: NMike Frysinger <vapier.adi@gmail.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      c3dc5bec
    • R
      [ARM] update mach-types · 6daad5c6
      由 Russell King 提交于 
      Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>
      6daad5c6
    • M
      [ARM] Add cmpxchg support for ARMv6+ systems (v5) · ecd322c9
      由 Mathieu Desnoyers 提交于 
      Add cmpxchg/cmpxchg64 support for ARMv6K and ARMv7 systems
(original patch from Catalin Marinas <catalin.marinas@arm.com>)

The cmpxchg and cmpxchg64 functions can be implemented using the
LDREX*/STREX* instructions. Since operand lengths other than 32bit are
required, the full implementations are only available if the ARMv6K
extensions are present (for the LDREXB, LDREXH and LDREXD instructions).

For ARMv6, only 32-bits cmpxchg is available.

Mathieu :

Make cmpxchg_local always available with best implementation for all type sizes (1, 2, 4 bytes).
Make cmpxchg64_local always available.

Use "Ir" constraint for "old" operand, like atomic.h atomic_cmpxchg does.

Change since v3 :
- Add "memory" clobbers (thanks to Nicolas Pitre)
- removed __asmeq(), only needed for old compilers, very unlikely on ARMv6+.

Note : ARMv7-M should eventually be ifdefed-out of cmpxchg64. But it's not
supported by the Linux kernel currently.

Put back arm < v6 cmpxchg support.
Signed-off-by: NMathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
CC: Catalin Marinas <catalin.marinas@arm.com>
CC: Nicolas Pitre <nico@cam.org>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>
      ecd322c9
    • R
      [ARM] barriers: improve xchg, bitops and atomic SMP barriers · bac4e960
      由 Russell King 提交于 
      Mathieu Desnoyers pointed out that the ARM barriers were lacking:

- cmpxchg, xchg and atomic add return need memory barriers on
  architectures which can reorder the relative order in which memory
  read/writes can be seen between CPUs, which seems to include recent
  ARM architectures. Those barriers are currently missing on ARM.

- test_and_xxx_bit were missing SMP barriers.

So put these barriers in.  Provide separate atomic_add/atomic_sub
operations which do not require barriers.
Reported-Reviewed-and-Acked-by: NMathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>
      bac4e960
  9. 28 5月, 2009 1 次提交
  11. 27 5月, 2009 2 次提交
    • B
      powerpc: Fix up dma_alloc_coherent() on platforms without cache coherency. · 8b31e49d
      由 Benjamin Herrenschmidt 提交于 
      The implementation we just revived has issues, such as using a
Kconfig-defined virtual address area in kernel space that nothing
actually carves out (and thus will overlap whatever is there),
or having some dependencies on being self contained in a single
PTE page which adds unnecessary constraints on the kernel virtual
address space.

This fixes it by using more classic PTE accessors and automatically
locating the area for consistent memory, carving an appropriate hole
in the kernel virtual address space, leaving only the size of that
area as a Kconfig option. It also brings some dma-mask related fixes
from the ARM implementation which was almost identical initially but
grew its own fixes.
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>
      8b31e49d
    • B
      powerpc: Minor cleanups of kernel virt address space definitions · f637a49e
      由 Benjamin Herrenschmidt 提交于 
      Make FIXADDR_TOP a compile time constant and cleanup a
couple of definitions relative to the layout of the kernel
address space on ppc32. We also print out that layout at
boot time for debugging purposes.

This is a pre-requisite for properly fixing non-coherent
DMA allocactions.
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>
      f637a49e