11 Sep, 2015
1 commit
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Hwpoison allows to filter pages by memory cgroup ino. Currently, it
calls try_get_mem_cgroup_from_page to obtain the cgroup from a page and
then its ino using cgroup_ino, but now we have a helper method for
that, page_cgroup_ino, so use it instead.This patch also loosens the hwpoison memcg filter dependency rules - it
makes it depend on CONFIG_MEMCG instead of CONFIG_MEMCG_SWAP, because
hwpoison memcg filter does not require anything (nor it used to) from
CONFIG_MEMCG_SWAP side.Signed-off-by: Vladimir Davydov
Reviewed-by: Andres Lagar-Cavilla
Cc: Minchan Kim
Cc: Raghavendra K T
Cc: Johannes Weiner
Cc: Michal Hocko
Cc: Greg Thelen
Cc: Michel Lespinasse
Cc: David Rientjes
Cc: Pavel Emelyanov
Cc: Cyrill Gorcunov
Cc: Jonathan Corbet
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
09 Sep, 2015
1 commit
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Hwpoison injection takes a refcount of target page and another refcount
of head page of THP if the target page is the tail page of a THP.
However, current code doesn't release the refcount of head page if the
THP is not supported to be injected wrt hwpoison filter.Fix it by reducing the refcount of head page if the target page is the
tail page of a THP and it is not supported to be injected.Signed-off-by: Wanpeng Li
Acked-by: Naoya Horiguchi
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
25 Jun, 2015
1 commit
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memory_failure() can run in 2 different mode (specified by
MF_COUNT_INCREASED) in page refcount perspective. When
MF_COUNT_INCREASED is set, memory_failure() assumes that the caller
takes a refcount of the target page. And if cleared, memory_failure()
takes it in it's own.In current code, however, refcounting is done differently in each caller.
For example, madvise_hwpoison() uses get_user_pages_fast() and
hwpoison_inject() uses get_page_unless_zero(). So this inconsistent
refcounting causes refcount failure especially for thp tail pages.
Typical user visible effects are like memory leak or
VM_BUG_ON_PAGE(!page_count(page)) in isolate_lru_page().To fix this refcounting issue, this patch introduces get_hwpoison_page()
to handle thp tail pages in the same manner for each caller of hwpoison
code.memory_failure() might fail to split thp and in such case it returns
without completing page isolation. This is not good because PageHWPoison
on the thp is still set and there's no easy way to unpoison such thps. So
this patch try to roll back any action to the thp in "non anonymous thp"
case and "thp split failed" case, expecting an MCE(SRAR) generated by
later access afterward will properly free such thps.[akpm@linux-foundation.org: fix CONFIG_HWPOISON_INJECT=m]
Signed-off-by: Naoya Horiguchi
Cc: Andi Kleen
Cc: Tony Luck
Cc: "Kirill A. Shutemov"
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
06 May, 2015
2 commits
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Hwpoison injector checks PageLRU of the raw target page to find out
whether the page is an appropriate target, but current code now filters
out thp tail pages, which prevents us from testing for such cases via this
interface. So let's check hpage instead of p.Signed-off-by: Naoya Horiguchi
Acked-by: Dean Nelson
Cc: Andi Kleen
Cc: Andrea Arcangeli
Cc: Hidetoshi Seto
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Hwpoison injection via debugfs:hwpoison/corrupt-pfn takes a refcount of
the target page. But current code doesn't release it if the target page
is not supposed to be injected, which results in memory leak. This patch
simply adds the refcount releasing code.Signed-off-by: Naoya Horiguchi
Acked-by: Dean Nelson
Cc: Andi Kleen
Cc: Andrea Arcangeli
Cc: Hidetoshi Seto
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
07 Aug, 2014
1 commit
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Fix checkpatch warning:
"WARNING: debugfs_remove_recursive(NULL) is safe this check is probably not required"Signed-off-by: Fabian Frederick
Acked-by: Naoya Horiguchi
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
22 Jan, 2014
1 commit
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Add '#' to hwpoison_inject just as done in madvise_hwpoison.
Signed-off-by: Wanpeng Li
Reviewed-by: Naoya Horiguchi
Reviewed-by: Vladimir Murzin
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
01 Oct, 2013
1 commit
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The lack of one reference count against poisoned page for hwpoison_inject
w/o hwpoison_filter enabled result in hwpoison detect -1 users still
referenced the page, however, the number should be 0 except the poison
handler held one after successfully unmap. This patch fix it by hold one
referenced count against poisoned page for hwpoison_inject w/ and w/o
hwpoison_filter enabled.Before patch:
[ 71.902112] Injecting memory failure at pfn 224706
[ 71.902137] MCE 0x224706: dirty LRU page recovery: Failed
[ 71.902138] MCE 0x224706: dirty LRU page still referenced by -1 usersAfter patch:
[ 94.710860] Injecting memory failure at pfn 215b68
[ 94.710885] MCE 0x215b68: dirty LRU page recovery: RecoveredReviewed-by: Naoya Horiguchi
Acked-by: Andi Kleen
Signed-off-by: Wanpeng Li
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
12 Sep, 2013
1 commit
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Hwpoison injection doesn't implement read method for
corrupt-pfn/unpoison-pfn attributes:# cat /sys/kernel/debug/hwpoison/corrupt-pfn
cat: /sys/kernel/debug/hwpoison/corrupt-pfn: Permission denied
# cat /sys/kernel/debug/hwpoison/unpoison-pfn
cat: /sys/kernel/debug/hwpoison/unpoison-pfn: Permission deniedThis patch changes the permission of corrupt-pfn/unpoison-pfn to 0200.
Signed-off-by: Wanpeng Li
Reviewed-by: Naoya Horiguchi
Cc: Andi Kleen
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
01 Aug, 2012
1 commit
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Sanity:
CONFIG_CGROUP_MEM_RES_CTLR -> CONFIG_MEMCG
CONFIG_CGROUP_MEM_RES_CTLR_SWAP -> CONFIG_MEMCG_SWAP
CONFIG_CGROUP_MEM_RES_CTLR_SWAP_ENABLED -> CONFIG_MEMCG_SWAP_ENABLED
CONFIG_CGROUP_MEM_RES_CTLR_KMEM -> CONFIG_MEMCG_KMEM[mhocko@suse.cz: fix missed bits]
Cc: Glauber Costa
Acked-by: Michal Hocko
Cc: Johannes Weiner
Cc: KAMEZAWA Hiroyuki
Cc: Hugh Dickins
Cc: Tejun Heo
Cc: Aneesh Kumar K.V
Cc: David Rientjes
Cc: KOSAKI Motohiro
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
04 Jan, 2012
1 commit
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There is only one caller of memory_failure(), all other users call
__memory_failure() and pass in the flags argument explicitly. The
lone user of memory_failure() will soon need to pass flags too.Add flags argument to the callsite in mce.c. Delete the old memory_failure()
function, and then rename __memory_failure() without the leading "__".Provide clearer message when action optional memory errors are ignored.
Acked-by: Borislav Petkov
Signed-off-by: Tony Luck
31 Mar, 2011
1 commit
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Fixes generated by 'codespell' and manually reviewed.
Signed-off-by: Lucas De Marchi
11 Aug, 2010
1 commit
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This patch enables hwpoison injection through debug/hwpoison interfaces,
with which we can test memory error handling for free or reserved
hugepages (which cannot be tested by madvise() injector).[AK: Export PageHuge too for the injection module]
Signed-off-by: Naoya Horiguchi
Cc: Andrew Morton
Acked-by: Fengguang Wu
Signed-off-by: Andi Kleen
16 Dec, 2009
8 commits
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Signed-off-by: Andi Kleen
-
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: Andi Kleen -
In some use cases, user doesn't need extra filtering. E.g. user program
can inject errors through madvise syscall to its own pages, however it
might not know what the page state exactly is or which inode the page
belongs to.So introduce an one-off interface "corrupt-filter-enable".
Echo 0 to switch off page filters, and echo 1 to switch on the filters.
[AK: changed default to 0]Signed-off-by: Haicheng Li
Signed-off-by: Wu Fengguang
Signed-off-by: Andi Kleen -
The hwpoison test suite need to inject hwpoison to a collection of
selected task pages, and must not touch pages not owned by them and
thus kill important system processes such as init. (But it's OK to
mis-hwpoison free/unowned pages as well as shared clean pages.
Mis-hwpoison of shared dirty pages will kill all tasks, so the test
suite will target all or non of such tasks in the first place.)The memory cgroup serves this purpose well. We can put the target
processes under the control of a memory cgroup, and tell the hwpoison
injection code to only kill pages associated with some active memory
cgroup.The prerequisite for doing hwpoison stress tests with mem_cgroup is,
the mem_cgroup code tracks task pages _accurately_ (unless page is
locked). Which we believe is/should be true.The benefits are simplification of hwpoison injector code. Also the
mem_cgroup code will automatically be tested by hwpoison test cases.The alternative interfaces pin-pfn/unpin-pfn can also delegate the
(process and page flags) filtering functions reliably to user space.
However prototype implementation shows that this scheme adds more
complexity than we wanted.Example test case:
mkdir /cgroup/hwpoison
usemem -m 100 -s 1000 &
echo `jobs -p` > /cgroup/hwpoison/tasksmemcg_ino=$(ls -id /cgroup/hwpoison | cut -f1 -d' ')
echo $memcg_ino > /debug/hwpoison/corrupt-filter-memcgpage-types -p `pidof init` --hwpoison # shall do nothing
page-types -p `pidof usemem` --hwpoison # poison its pages[AK: Fix documentation]
[Add fix for problem noticed by Li Zefan ;
dentry in the css could be NULL]CC: KOSAKI Motohiro
CC: Hugh Dickins
CC: Daisuke Nishimura
CC: Balbir Singh
CC: KAMEZAWA Hiroyuki
CC: Li Zefan
CC: Paul Menage
CC: Nick Piggin
CC: Andi Kleen
Signed-off-by: Wu Fengguang
Signed-off-by: Andi Kleen -
When specified, only poison pages if ((page_flags & mask) == value).
- corrupt-filter-flags-mask
- corrupt-filter-flags-valueThis allows stress testing of many kinds of pages.
Strictly speaking, the buddy pages requires taking zone lock, to avoid
setting PG_hwpoison on a "was buddy but now allocated to someone" page.
However we can just do nothing because we set PG_locked in the beginning,
this prevents the page allocator from allocating it to someone. (It will
BUG() on the unexpected PG_locked, which is fine for hwpoison testing.)[AK: Add select PROC_PAGE_MONITOR to satisfy dependency]
CC: Nick Piggin
Signed-off-by: Wu Fengguang
Signed-off-by: Andi Kleen -
__memory_failure()'s workflow is
set PG_hwpoison
//...
unset PG_hwpoison if didn't pass hwpoison filterThat could kill unrelated process if it happens to page fault on the
page with the (temporary) PG_hwpoison. The race should be big enough to
appear in stress tests.Fix it by grabbing the page and checking filter at inject time. This
also avoids the very noisy "Injecting memory failure..." messages.- we don't touch madvise() based injection, because the filters are
generally not necessary for it.
- if we want to apply the filters to h/w aided injection, we'd better to
rearrange the logic in __memory_failure() instead of this patch.AK: fix documentation, use drain all, cleanups
CC: Haicheng Li
Signed-off-by: Wu Fengguang
Signed-off-by: Andi Kleen -
Filesystem data/metadata present the most tricky-to-isolate pages.
It requires careful code review and stress testing to get them right.The fs/device filter helps to target the stress tests to some specific
filesystem pages. The filter condition is block device's major/minor
numbers:
- corrupt-filter-dev-major
- corrupt-filter-dev-minor
When specified (non -1), only page cache pages that belong to that
device will be poisoned.The filters are checked reliably on the locked and refcounted page.
Haicheng: clear PG_hwpoison and drop bad page count if filter not OK
AK: Add documentationCC: Haicheng Li
CC: Nick Piggin
Signed-off-by: Wu Fengguang
Signed-off-by: Andi Kleen -
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: Wu Fengguang
Signed-off-by: Andi Kleen
16 Sep, 2009
1 commit
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Useful for some testing scenarios, although specific testing is often
done better through MADV_POISONThis can be done with the x86 level MCE injector too, but this interface
allows it to do independently from low level x86 changes.v2: Add module license (Haicheng Li)
Signed-off-by: Andi Kleen