1. 02 2月, 2010 1 次提交
  2. 17 1月, 2010 1 次提交
    • D
      nommu: fix shared mmap after truncate shrinkage problems · 7e660872
      David Howells 提交于
      Fix a problem in NOMMU mmap with ramfs whereby a shared mmap can happen
      over the end of a truncation.  The problem is that
      ramfs_nommu_check_mappings() checks that the reduced file size against the
      VMA tree, but not the vm_region tree.
      
      The following sequence of events can cause the problem:
      
      	fd = open("/tmp/x", O_RDWR|O_TRUNC|O_CREAT, 0600);
      	ftruncate(fd, 32 * 1024);
      	a = mmap(NULL, 32 * 1024, PROT_READ|PROT_WRITE, MAP_SHARED, fd, 0);
      	b = mmap(NULL, 16 * 1024, PROT_READ|PROT_WRITE, MAP_SHARED, fd, 0);
      	munmap(a, 32 * 1024);
      	ftruncate(fd, 16 * 1024);
      	c = mmap(NULL, 32 * 1024, PROT_READ|PROT_WRITE, MAP_SHARED, fd, 0);
      
      Mapping 'a' creates a vm_region covering 32KB of the file.  Mapping 'b'
      sees that the vm_region from 'a' is covering the region it wants and so
      shares it, pinning it in memory.
      
      Mapping 'a' then goes away and the file is truncated to the end of VMA
      'b'.  However, the region allocated by 'a' is still in effect, and has
      _not_ been reduced.
      
      Mapping 'c' is then created, and because there's a vm_region covering the
      desired region, get_unmapped_area() is _not_ called to repeat the check,
      and the mapping is granted, even though the pages from the latter half of
      the mapping have been discarded.
      
      However:
      
      	d = mmap(NULL, 16 * 1024, PROT_READ|PROT_WRITE, MAP_SHARED, fd, 0);
      
      Mapping 'd' should work, and should end up sharing the region allocated by
      'a'.
      
      To deal with this, we shrink the vm_region struct during the truncation,
      lest do_mmap_pgoff() take it as licence to share the full region
      automatically without calling the get_unmapped_area() file op again.
      Signed-off-by: NDavid Howells <dhowells@redhat.com>
      Acked-by: NAl Viro <viro@zeniv.linux.org.uk>
      Cc: Greg Ungerer <gerg@snapgear.com>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      7e660872
  3. 17 12月, 2009 1 次提交
    • Y
      x86: Fix checking of SRAT when node 0 ram is not from 0 · 32996250
      Yinghai Lu 提交于
      Found one system that boot from socket1 instead of socket0, SRAT get rejected...
      
      [    0.000000] SRAT: Node 1 PXM 0 0-a0000
      [    0.000000] SRAT: Node 1 PXM 0 100000-80000000
      [    0.000000] SRAT: Node 1 PXM 0 100000000-2080000000
      [    0.000000] SRAT: Node 0 PXM 1 2080000000-4080000000
      [    0.000000] SRAT: Node 2 PXM 2 4080000000-6080000000
      [    0.000000] SRAT: Node 3 PXM 3 6080000000-8080000000
      [    0.000000] SRAT: Node 4 PXM 4 8080000000-a080000000
      [    0.000000] SRAT: Node 5 PXM 5 a080000000-c080000000
      [    0.000000] SRAT: Node 6 PXM 6 c080000000-e080000000
      [    0.000000] SRAT: Node 7 PXM 7 e080000000-10080000000
      ...
      [    0.000000] NUMA: Allocated memnodemap from 500000 - 701040
      [    0.000000] NUMA: Using 20 for the hash shift.
      [    0.000000] Adding active range (0, 0x2080000, 0x4080000) 0 entries of 3200 used
      [    0.000000] Adding active range (1, 0x0, 0x96) 1 entries of 3200 used
      [    0.000000] Adding active range (1, 0x100, 0x7f750) 2 entries of 3200 used
      [    0.000000] Adding active range (1, 0x100000, 0x2080000) 3 entries of 3200 used
      [    0.000000] Adding active range (2, 0x4080000, 0x6080000) 4 entries of 3200 used
      [    0.000000] Adding active range (3, 0x6080000, 0x8080000) 5 entries of 3200 used
      [    0.000000] Adding active range (4, 0x8080000, 0xa080000) 6 entries of 3200 used
      [    0.000000] Adding active range (5, 0xa080000, 0xc080000) 7 entries of 3200 used
      [    0.000000] Adding active range (6, 0xc080000, 0xe080000) 8 entries of 3200 used
      [    0.000000] Adding active range (7, 0xe080000, 0x10080000) 9 entries of 3200 used
      [    0.000000] SRAT: PXMs only cover 917504MB of your 1048566MB e820 RAM. Not used.
      [    0.000000] SRAT: SRAT not used.
      
      the early_node_map is not sorted because node0 with non zero start come first.
      
      so try to sort it right away after all regions are registered.
      
      also fixs refression by 8716273c (x86: Export srat physical topology)
      
      -v2: make it more solid to handle cross node case like node0 [0,4g), [8,12g) and node1 [4g, 8g), [12g, 16g)
      -v3: update comments.
      Reported-and-tested-by: NJens Axboe <jens.axboe@oracle.com>
      Signed-off-by: NYinghai Lu <yinghai@kernel.org>
      LKML-Reference: <4B2579D2.3010201@kernel.org>
      Signed-off-by: NH. Peter Anvin <hpa@zytor.com>
      32996250
  4. 16 12月, 2009 7 次提交
    • A
      HWPOISON: Add soft page offline support · facb6011
      Andi Kleen 提交于
      This is a simpler, gentler variant of memory_failure() for soft page
      offlining controlled from user space.  It doesn't kill anything, just
      tries to invalidate and if that doesn't work migrate the
      page away.
      
      This is useful for predictive failure analysis, where a page has
      a high rate of corrected errors, but hasn't gone bad yet. Instead
      it can be offlined early and avoided.
      
      The offlining is controlled from sysfs, including a new generic
      entry point for hard page offlining for symmetry too.
      
      We use the page isolate facility to prevent re-allocation
      race. Normally this is only used by memory hotplug. To avoid
      races with memory allocation I am using lock_system_sleep().
      This avoids the situation where memory hotplug is about
      to isolate a page range and then hwpoison undoes that work.
      This is a big hammer currently, but the simplest solution
      currently.
      
      When the page is not free or LRU we try to free pages
      from slab and other caches. The slab freeing is currently
      quite dumb and does not try to focus on the specific slab
      cache which might own the page. This could be potentially
      improved later.
      
      Thanks to Fengguang Wu and Haicheng Li for some fixes.
      
      [Added fix from Andrew Morton to adapt to new migrate_pages prototype]
      Signed-off-by: NAndi Kleen <ak@linux.intel.com>
      facb6011
    • W
      HWPOISON: Add unpoisoning support · 847ce401
      Wu Fengguang 提交于
      The unpoisoning interface is useful for stress testing tools to
      reclaim poisoned pages (to prevent OOM)
      
      There is no hardware level unpoisioning, so this
      cannot be used for real memory errors, only for software injected errors.
      
      Note that it may leak pages silently - those who have been removed from
      LRU cache, but not isolated from page cache/swap cache at hwpoison time.
      Especially the stress test of dirty swap cache pages shall reboot system
      before exhausting memory.
      
      AK: Fix comments, add documentation, add printks, rename symbol
      Signed-off-by: NWu Fengguang <fengguang.wu@intel.com>
      Signed-off-by: NAndi Kleen <ak@linux.intel.com>
      847ce401
    • A
      HWPOISON: Turn ref argument into flags argument · 82ba011b
      Andi Kleen 提交于
      Now that "ref" is just a boolean turn it into
      a flags argument. First step is only a single flag
      that makes the code's intention more clear, but more
      may follow.
      Signed-off-by: NAndi Kleen <ak@linux.intel.com>
      82ba011b
    • A
      HWPOISON: Be more aggressive at freeing non LRU caches · 588f9ce6
      Andi Kleen 提交于
      shake_page handles more types of page caches than lru_drain_all()
      
      - per cpu page allocator pages
      - per CPU LRU
      
      Stops early when the page became free.
      
      Used in followon patches.
      Signed-off-by: NAndi Kleen <ak@linux.intel.com>
      588f9ce6
    • N
      mm hugetlb: add hugepage support to pagemap · 5dc37642
      Naoya Horiguchi 提交于
      This patch enables extraction of the pfn of a hugepage from
      /proc/pid/pagemap in an architecture independent manner.
      
      Details
      -------
      My test program (leak_pagemap) works as follows:
       - creat() and mmap() a file on hugetlbfs (file size is 200MB == 100 hugepages,)
       - read()/write() something on it,
       - call page-types with option -p,
       - munmap() and unlink() the file on hugetlbfs
      
      Without my patches
      ------------------
      $ ./leak_pagemap
                   flags page-count       MB  symbolic-flags                     long-symbolic-flags
      0x0000000000000000          1        0  __________________________________
      0x0000000000000804          1        0  __R________M______________________ referenced,mmap
      0x000000000000086c         81        0  __RU_lA____M______________________ referenced,uptodate,lru,active,mmap
      0x0000000000005808          5        0  ___U_______Ma_b___________________ uptodate,mmap,anonymous,swapbacked
      0x0000000000005868         12        0  ___U_lA____Ma_b___________________ uptodate,lru,active,mmap,anonymous,swapbacked
      0x000000000000586c          1        0  __RU_lA____Ma_b___________________ referenced,uptodate,lru,active,mmap,anonymous,swapbacked
                   total        101        0
      
      The output of page-types don't show any hugepage.
      
      With my patches
      ---------------
      $ ./leak_pagemap
                   flags page-count       MB  symbolic-flags                     long-symbolic-flags
      0x0000000000000000          1        0  __________________________________
      0x0000000000030000      51100      199  ________________TG________________ compound_tail,huge
      0x0000000000028018        100        0  ___UD__________H_G________________ uptodate,dirty,compound_head,huge
      0x0000000000000804          1        0  __R________M______________________ referenced,mmap
      0x000000000000080c          1        0  __RU_______M______________________ referenced,uptodate,mmap
      0x000000000000086c         80        0  __RU_lA____M______________________ referenced,uptodate,lru,active,mmap
      0x0000000000005808          4        0  ___U_______Ma_b___________________ uptodate,mmap,anonymous,swapbacked
      0x0000000000005868         12        0  ___U_lA____Ma_b___________________ uptodate,lru,active,mmap,anonymous,swapbacked
      0x000000000000586c          1        0  __RU_lA____Ma_b___________________ referenced,uptodate,lru,active,mmap,anonymous,swapbacked
                   total      51300      200
      
      The output of page-types shows 51200 pages contributing to hugepages,
      containing 100 head pages and 51100 tail pages as expected.
      
      [akpm@linux-foundation.org: build fix]
      Signed-off-by: NNaoya Horiguchi <n-horiguchi@ah.jp.nec.com>
      Cc: Andi Kleen <ak@linux.intel.com>
      Cc: Wu Fengguang <fengguang.wu@intel.com>
      Cc: Hugh Dickins <hugh.dickins@tiscali.co.uk>
      Cc: Mel Gorman <mel@csn.ul.ie>
      Cc: Lee Schermerhorn <lee.schermerhorn@hp.com>
      Cc: Andy Whitcroft <apw@canonical.com>
      Cc: David Rientjes <rientjes@google.com>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      5dc37642
    • H
      include/linux/mm.h: remove unneeded ifdef · f096e59e
      Huang Shijie 提交于
      The check code for CONFIG_SWAP is redundant, because there is a
      non-CONFIG_SWAP version for PageSwapCache() which just returns 0.
      Signed-off-by: NHuang Shijie <shijie8@gmail.com>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      f096e59e
    • H
      mm: define PAGE_MAPPING_FLAGS · 3ca7b3c5
      Hugh Dickins 提交于
      At present we define PageAnon(page) by the low PAGE_MAPPING_ANON bit set
      in page->mapping, with the higher bits a pointer to the anon_vma; and have
      defined PageKsm(page) as that with NULL anon_vma.
      
      But KSM swapping will need to store a pointer there: so in preparation for
      that, now define PAGE_MAPPING_FLAGS as the low two bits, including
      PAGE_MAPPING_KSM (always set along with PAGE_MAPPING_ANON, until some
      other use for the bit emerges).
      
      Declare page_rmapping(page) to return the pointer part of page->mapping,
      and page_anon_vma(page) to return the anon_vma pointer when that's what it
      is.  Use these in a few appropriate places: notably, unuse_vma() has been
      testing page->mapping, but is better to be testing page_anon_vma() (cases
      may be added in which flag bits are set without any pointer).
      Signed-off-by: NHugh Dickins <hugh.dickins@tiscali.co.uk>
      Cc: Izik Eidus <ieidus@redhat.com>
      Cc: Andrea Arcangeli <aarcange@redhat.com>
      Cc: Nick Piggin <npiggin@suse.de>
      Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
      Reviewed-by: NRik van Riel <riel@redhat.com>
      Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
      Cc: Andi Kleen <andi@firstfloor.org>
      Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
      Cc: Wu Fengguang <fengguang.wu@intel.com>
      Cc: Minchan Kim <minchan.kim@gmail.com>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      3ca7b3c5
  5. 25 9月, 2009 1 次提交
  6. 24 9月, 2009 2 次提交
  7. 23 9月, 2009 1 次提交
  8. 22 9月, 2009 7 次提交
    • H
      tmpfs: depend on shmem · 3f96b79a
      Hugh Dickins 提交于
      CONFIG_SHMEM off gives you (ramfs masquerading as) tmpfs, even when
      CONFIG_TMPFS is off: that's a little anomalous, and I'd intended to make
      more sense of it by removing CONFIG_TMPFS altogether, always enabling its
      code when CONFIG_SHMEM; but so many defconfigs have CONFIG_SHMEM on
      CONFIG_TMPFS off that we'd better leave that as is.
      
      But there is no point in asking for CONFIG_TMPFS if CONFIG_SHMEM is off:
      make TMPFS depend on SHMEM, which also prevents TMPFS_POSIX_ACL
      shmem_acl.o being pointlessly built into the kernel when SHMEM is off.
      
      And a selfish change, to prevent the world from being rebuilt when I
      switch between CONFIG_SHMEM on and off: the only CONFIG_SHMEM in the
      header files is mm.h shmem_lock() - give that a shmem.c stub instead.
      Signed-off-by: NHugh Dickins <hugh.dickins@tiscali.co.uk>
      Acked-by: NMatt Mackall <mpm@selenic.com>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      3f96b79a
    • H
      mm: FOLL flags for GUP flags · 58fa879e
      Hugh Dickins 提交于
      __get_user_pages() has been taking its own GUP flags, then processing
      them into FOLL flags for follow_page().  Though oddly named, the FOLL
      flags are more widely used, so pass them to __get_user_pages() now.
      Sorry, VM flags, VM_FAULT flags and FAULT_FLAGs are still distinct.
      
      (The patch to __get_user_pages() looks peculiar, with both gup_flags
      and foll_flags: the gup_flags remain constant; but as before there's
      an exceptional case, out of scope of the patch, in which foll_flags
      per page have FOLL_WRITE masked off.)
      Signed-off-by: NHugh Dickins <hugh.dickins@tiscali.co.uk>
      Cc: Rik van Riel <riel@redhat.com>
      Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
      Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
      Cc: Nick Piggin <npiggin@suse.de>
      Cc: Mel Gorman <mel@csn.ul.ie>
      Cc: Minchan Kim <minchan.kim@gmail.com>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      58fa879e
    • H
      mm: FOLL_DUMP replace FOLL_ANON · 8e4b9a60
      Hugh Dickins 提交于
      The "FOLL_ANON optimization" and its use_zero_page() test have caused
      confusion and bugs: why does it test VM_SHARED? for the very good but
      unsatisfying reason that VMware crashed without.  As we look to maybe
      reinstating anonymous use of the ZERO_PAGE, we need to sort this out.
      
      Easily done: it's silly for __get_user_pages() and follow_page() to
      be guessing whether it's safe to assume that they're being used for
      a coredump (which can take a shortcut snapshot where other uses must
      handle a fault) - just tell them with GUP_FLAGS_DUMP and FOLL_DUMP.
      
      get_dump_page() doesn't even want a ZERO_PAGE: an error suits fine.
      Signed-off-by: NHugh Dickins <hugh.dickins@tiscali.co.uk>
      Acked-by: NRik van Riel <riel@redhat.com>
      Acked-by: NMel Gorman <mel@csn.ul.ie>
      Reviewed-by: NMinchan Kim <minchan.kim@gmail.com>
      Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
      Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
      Cc: Nick Piggin <npiggin@suse.de>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      8e4b9a60
    • H
      mm: add get_dump_page · f3e8fccd
      Hugh Dickins 提交于
      In preparation for the next patch, add a simple get_dump_page(addr)
      interface for the CONFIG_ELF_CORE dumpers to use, instead of calling
      get_user_pages() directly.  They're not interested in errors: they
      just want to use holes as much as possible, to save space and make
      sure that the data is aligned where the headers said it would be.
      
      Oh, and don't use that horrid DUMP_SEEK(off) macro!
      Signed-off-by: NHugh Dickins <hugh.dickins@tiscali.co.uk>
      Acked-by: NRik van Riel <riel@redhat.com>
      Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
      Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
      Cc: Nick Piggin <npiggin@suse.de>
      Cc: Mel Gorman <mel@csn.ul.ie>
      Cc: Minchan Kim <minchan.kim@gmail.com>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      f3e8fccd
    • J
      mm: replace various uses of num_physpages by totalram_pages · 4481374c
      Jan Beulich 提交于
      Sizing of memory allocations shouldn't depend on the number of physical
      pages found in a system, as that generally includes (perhaps a huge amount
      of) non-RAM pages.  The amount of what actually is usable as storage
      should instead be used as a basis here.
      
      Some of the calculations (i.e.  those not intending to use high memory)
      should likely even use (totalram_pages - totalhigh_pages).
      Signed-off-by: NJan Beulich <jbeulich@novell.com>
      Acked-by: NRusty Russell <rusty@rustcorp.com.au>
      Acked-by: NIngo Molnar <mingo@elte.hu>
      Cc: Dave Airlie <airlied@linux.ie>
      Cc: Kyle McMartin <kyle@mcmartin.ca>
      Cc: Jeremy Fitzhardinge <jeremy@goop.org>
      Cc: Pekka Enberg <penberg@cs.helsinki.fi>
      Cc: Hugh Dickins <hugh.dickins@tiscali.co.uk>
      Cc: "David S. Miller" <davem@davemloft.net>
      Cc: Patrick McHardy <kaber@trash.net>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      4481374c
    • H
      ksm: the mm interface to ksm · f8af4da3
      Hugh Dickins 提交于
      This patch presents the mm interface to a dummy version of ksm.c, for
      better scrutiny of that interface: the real ksm.c follows later.
      
      When CONFIG_KSM is not set, madvise(2) reject MADV_MERGEABLE and
      MADV_UNMERGEABLE with EINVAL, since that seems more helpful than
      pretending that they can be serviced.  But when CONFIG_KSM=y, accept them
      even if KSM is not currently running, and even on areas which KSM will not
      touch (e.g.  hugetlb or shared file or special driver mappings).
      
      Like other madvices, report ENOMEM despite success if any area in the
      range is unmapped, and use EAGAIN to report out of memory.
      
      Define vma flag VM_MERGEABLE to identify an area on which KSM may try
      merging pages: leave it to ksm_madvise() to decide whether to set it.
      Define mm flag MMF_VM_MERGEABLE to identify an mm which might contain
      VM_MERGEABLE areas, to minimize callouts when forking or exiting.
      
      Based upon earlier patches by Chris Wright and Izik Eidus.
      Signed-off-by: NHugh Dickins <hugh.dickins@tiscali.co.uk>
      Signed-off-by: NChris Wright <chrisw@redhat.com>
      Signed-off-by: NIzik Eidus <ieidus@redhat.com>
      Cc: Michael Kerrisk <mtk.manpages@gmail.com>
      Cc: Andrea Arcangeli <aarcange@redhat.com>
      Cc: Rik van Riel <riel@redhat.com>
      Cc: Wu Fengguang <fengguang.wu@intel.com>
      Cc: Balbir Singh <balbir@in.ibm.com>
      Cc: Hugh Dickins <hugh.dickins@tiscali.co.uk>
      Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
      Cc: Lee Schermerhorn <lee.schermerhorn@hp.com>
      Cc: Avi Kivity <avi@redhat.com>
      Cc: Nick Piggin <nickpiggin@yahoo.com.au>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      f8af4da3
    • S
      memory hotplug: update zone pcp at memory online · 112067f0
      Shaohua Li 提交于
      In my test, 128M memory is hot added, but zone's pcp batch is 0, which is
      an obvious error.  When pages are onlined, zone pcp should be updated
      accordingly.
      
      [akpm@linux-foundation.org: fix warnings]
      Signed-off-by: NShaohua Li <shaohua.li@intel.com>
      Cc: Mel Gorman <mel@csn.ul.ie>
      Cc: Christoph Lameter <cl@linux-foundation.org>
      Cc: Yakui Zhao <yakui.zhao@intel.com>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      112067f0
  9. 16 9月, 2009 5 次提交
    • A
      HWPOISON: The high level memory error handler in the VM v7 · 6a46079c
      Andi Kleen 提交于
      Add the high level memory handler that poisons pages
      that got corrupted by hardware (typically by a two bit flip in a DIMM
      or a cache) on the Linux level. The goal is to prevent everyone
      from accessing these pages in the future.
      
      This done at the VM level by marking a page hwpoisoned
      and doing the appropriate action based on the type of page
      it is.
      
      The code that does this is portable and lives in mm/memory-failure.c
      
      To quote the overview comment:
      
      High level machine check handler. Handles pages reported by the
      hardware as being corrupted usually due to a 2bit ECC memory or cache
      failure.
      
      This focuses on pages detected as corrupted in the background.
      When the current CPU tries to consume corruption the currently
      running process can just be killed directly instead. This implies
      that if the error cannot be handled for some reason it's safe to
      just ignore it because no corruption has been consumed yet. Instead
      when that happens another machine check will happen.
      
      Handles page cache pages in various states. The tricky part
      here is that we can access any page asynchronous to other VM
      users, because memory failures could happen anytime and anywhere,
      possibly violating some of their assumptions. This is why this code
      has to be extremely careful. Generally it tries to use normal locking
      rules, as in get the standard locks, even if that means the
      error handling takes potentially a long time.
      
      Some of the operations here are somewhat inefficient and have non
      linear algorithmic complexity, because the data structures have not
      been optimized for this case. This is in particular the case
      for the mapping from a vma to a process. Since this case is expected
      to be rare we hope we can get away with this.
      
      There are in principle two strategies to kill processes on poison:
      - just unmap the data and wait for an actual reference before
      killing
      - kill as soon as corruption is detected.
      Both have advantages and disadvantages and should be used
      in different situations. Right now both are implemented and can
      be switched with a new sysctl vm.memory_failure_early_kill
      The default is early kill.
      
      The patch does some rmap data structure walking on its own to collect
      processes to kill. This is unusual because normally all rmap data structure
      knowledge is in rmap.c only. I put it here for now to keep
      everything together and rmap knowledge has been seeping out anyways
      
      Includes contributions from Johannes Weiner, Chris Mason, Fengguang Wu,
      Nick Piggin (who did a lot of great work) and others.
      
      Cc: npiggin@suse.de
      Cc: riel@redhat.com
      Signed-off-by: NAndi Kleen <ak@linux.intel.com>
      Acked-by: NRik van Riel <riel@redhat.com>
      Reviewed-by: NHidehiro Kawai <hidehiro.kawai.ez@hitachi.com>
      6a46079c
    • A
      HWPOISON: Define a new error_remove_page address space op for async truncation · 25718736
      Andi Kleen 提交于
      Truncating metadata pages is not safe right now before
      we haven't audited all file systems.
      
      To enable truncation only for data address space define
      a new address_space callback error_remove_page.
      
      This is used for memory_failure.c memory error handling.
      
      This can be then set to truncate_inode_page()
      
      This patch just defines the new operation and adds documentation.
      
      Callers and users come in followon patches.
      Signed-off-by: NAndi Kleen <ak@linux.intel.com>
      25718736
    • W
      HWPOISON: Add invalidate_inode_page · 83f78668
      Wu Fengguang 提交于
      Add a simple way to invalidate a single page
      This is just a refactoring of the truncate.c code.
      Originally from Fengguang, modified by Andi Kleen.
      Signed-off-by: NAndi Kleen <ak@linux.intel.com>
      83f78668
    • N
      HWPOISON: Refactor truncate to allow direct truncating of page v2 · 750b4987
      Nick Piggin 提交于
      Extract out truncate_inode_page() out of the truncate path so that
      it can be used by memory-failure.c
      
      [AK: description, headers, fix typos]
      v2: Some white space changes from Fengguang Wu
      Signed-off-by: NAndi Kleen <ak@linux.intel.com>
      750b4987
    • A
      HWPOISON: Add basic support for poisoned pages in fault handler v3 · d1737fdb
      Andi Kleen 提交于
      - Add a new VM_FAULT_HWPOISON error code to handle_mm_fault. Right now
      architectures have to explicitely enable poison page support, so
      this is forward compatible to all architectures. They only need
      to add it when they enable poison page support.
      - Add poison page handling in swap in fault code
      
      v2: Add missing delayacct_clear_flag (Hidehiro Kawai)
      v3: Really use delayacct_clear_flag (Hidehiro Kawai)
      Signed-off-by: NAndi Kleen <ak@linux.intel.com>
      d1737fdb
  10. 17 8月, 2009 1 次提交
    • E
      Security/SELinux: seperate lsm specific mmap_min_addr · 788084ab
      Eric Paris 提交于
      Currently SELinux enforcement of controls on the ability to map low memory
      is determined by the mmap_min_addr tunable.  This patch causes SELinux to
      ignore the tunable and instead use a seperate Kconfig option specific to how
      much space the LSM should protect.
      
      The tunable will now only control the need for CAP_SYS_RAWIO and SELinux
      permissions will always protect the amount of low memory designated by
      CONFIG_LSM_MMAP_MIN_ADDR.
      
      This allows users who need to disable the mmap_min_addr controls (usual reason
      being they run WINE as a non-root user) to do so and still have SELinux
      controls preventing confined domains (like a web server) from being able to
      map some area of low memory.
      Signed-off-by: NEric Paris <eparis@redhat.com>
      Signed-off-by: NJames Morris <jmorris@namei.org>
      788084ab
  11. 06 8月, 2009 1 次提交
    • E
      Security/SELinux: seperate lsm specific mmap_min_addr · a2551df7
      Eric Paris 提交于
      Currently SELinux enforcement of controls on the ability to map low memory
      is determined by the mmap_min_addr tunable.  This patch causes SELinux to
      ignore the tunable and instead use a seperate Kconfig option specific to how
      much space the LSM should protect.
      
      The tunable will now only control the need for CAP_SYS_RAWIO and SELinux
      permissions will always protect the amount of low memory designated by
      CONFIG_LSM_MMAP_MIN_ADDR.
      
      This allows users who need to disable the mmap_min_addr controls (usual reason
      being they run WINE as a non-root user) to do so and still have SELinux
      controls preventing confined domains (like a web server) from being able to
      map some area of low memory.
      Signed-off-by: NEric Paris <eparis@redhat.com>
      Signed-off-by: NJames Morris <jmorris@namei.org>
      a2551df7
  12. 26 6月, 2009 1 次提交
  13. 22 6月, 2009 1 次提交
  14. 17 6月, 2009 7 次提交
  15. 15 6月, 2009 1 次提交
  16. 04 6月, 2009 1 次提交
  17. 18 5月, 2009 1 次提交
    • Y
      mm, x86: remove MEMORY_HOTPLUG_RESERVE related code · 888a589f
      Yinghai Lu 提交于
      after:
      
       | commit b263295d
       | Author: Christoph Lameter <clameter@sgi.com>
       | Date:   Wed Jan 30 13:30:47 2008 +0100
       |
       |    x86: 64-bit, make sparsemem vmemmap the only memory model
      
      we don't have MEMORY_HOTPLUG_RESERVE anymore.
      
      Historically, x86-64 had an architecture-specific method for memory hotplug
      whereby it scanned the SRAT for physical memory ranges that could be
      potentially used for memory hot-add later. By reserving those ranges
      without physical memory, the memmap would be allocated and left dormant
      until needed. This depended on the DISCONTIG memory model which has been
      removed so the code implementing HOTPLUG_RESERVE is now dead.
      
      This patch removes the dead code used by MEMORY_HOTPLUG_RESERVE.
      
      (Changelog authored by Mel.)
      
      v2: updated changelog, and remove hotadd= in doc
      
      [ Impact: remove dead code ]
      Signed-off-by: NYinghai Lu <yinghai@kernel.org>
      Reviewed-by: NChristoph Lameter <cl@linux-foundation.org>
      Reviewed-by: NMel Gorman <mel@csn.ul.ie>
      Workflow-found-OK-by: NAndrew Morton <akpm@linux-foundation.org>
      LKML-Reference: <4A0C4910.7090508@kernel.org>
      Signed-off-by: NIngo Molnar <mingo@elte.hu>
      888a589f