Patch series "Introduce per NUMA node memory error statistics", v2.
Background
==========
In the RFC for Kernel Support of Memory Error Detection [1], one advantage
of software-based scanning over hardware patrol scrubber is the ability to
make statistics visible to system administrators. The statistics include
2 categories:
* Memory error statistics, for example, how many memory error are
encountered, how many of them are recovered by the kernel. Note these
memory errors are non-fatal to kernel: during the machine check
exception (MCE) handling kernel already classified MCE's severity to be
unnecessary to panic (but either action required or optional).
* Scanner statistics, for example how many times the scanner have fully
scanned a NUMA node, how many errors are first detected by the scanner.
The memory error statistics are useful to userspace and actually not
specific to scanner detected memory errors, and are the focus of this
patchset.
Motivation
==========
Memory error stats are important to userspace but insufficient in kernel
today. Datacenter administrators can better monitor a machine's memory
health with the visible stats. For example, while memory errors are
inevitable on servers with 10+ TB memory, starting server maintenance when
there are only 1~2 recovered memory errors could be overreacting; in cloud
production environment maintenance usually means live migrate all the
workload running on the server and this usually causes nontrivial
disruption to the customer. Providing insight into the scope of memory
errors on a system helps to determine the appropriate follow-up action.
In addition, the kernel's existing memory error stats need to be
standardized so that userspace can reliably count on their usefulness.
Today kernel provides following memory error info to userspace, but they
are not sufficient or have disadvantages:
* HardwareCorrupted in /proc/meminfo: number of bytes poisoned in total,
not per NUMA node stats though
* ras:memory_failure_event: only available after explicitly enabled
* /dev/mcelog provides many useful info about the MCEs, but doesn't
capture how memory_failure recovered memory MCEs
* kernel logs: userspace needs to process log text
Exposing memory error stats is also a good start for the in-kernel memory
error detector. Today the data source of memory error stats are either
direct memory error consumption, or hardware patrol scrubber detection
(either signaled as UCNA or SRAO). Once in-kernel memory scanner is
implemented, it will be the main source as it is usually configured to
scan memory DIMMs constantly and faster than hardware patrol scrubber.
How Implemented
===============
As Naoya pointed out [2], exposing memory error statistics to userspace is
useful independent of software or hardware scanner. Therefore we
implement the memory error statistics independent of the in-kernel memory
error detector. It exposes the following per NUMA node memory error
counters:
/sys/devices/system/node/node${X}/memory_failure/total
/sys/devices/system/node/node${X}/memory_failure/recovered
/sys/devices/system/node/node${X}/memory_failure/ignored
/sys/devices/system/node/node${X}/memory_failure/failed
/sys/devices/system/node/node${X}/memory_failure/delayed
These counters describe how many raw pages are poisoned and after the
attempted recoveries by the kernel, their resolutions: how many are
recovered, ignored, failed, or delayed respectively. This approach can be
easier to extend for future use cases than /proc/meminfo, trace event, and
log. The following math holds for the statistics:
* total = recovered + ignored + failed + delayed
These memory error stats are reset during machine boot.
The 1st commit introduces these sysfs entries. The 2nd commit populates
memory error stats every time memory_failure attempts memory error
recovery. The 3rd commit adds documentations for introduced stats.
[1] https://lore.kernel.org/linux-mm/7E670362-C29E-4626-B546-26530D54F937@gmail.com/T/#mc22959244f5388891c523882e61163c6e4d703af
[2] https://lore.kernel.org/linux-mm/7E670362-C29E-4626-B546-26530D54F937@gmail.com/T/#m52d8d7a333d8536bd7ce74253298858b1c0c0ac6
This patch (of 3):
Today kernel provides following memory error info to userspace, but each
has its own disadvantage
* HardwareCorrupted in /proc/meminfo: number of bytes poisoned in total,
not per NUMA node stats though
* ras:memory_failure_event: only available after explicitly enabled
* /dev/mcelog provides many useful info about the MCEs, but
doesn't capture how memory_failure recovered memory MCEs
* kernel logs: userspace needs to process log text
Exposes per NUMA node memory error stats as sysfs entries:
/sys/devices/system/node/node${X}/memory_failure/total
/sys/devices/system/node/node${X}/memory_failure/recovered
/sys/devices/system/node/node${X}/memory_failure/ignored
/sys/devices/system/node/node${X}/memory_failure/failed
/sys/devices/system/node/node${X}/memory_failure/delayed
These counters describe how many raw pages are poisoned and after the
attempted recoveries by the kernel, their resolutions: how many are
recovered, ignored, failed, or delayed respectively. The following math
holds for the statistics:
* total = recovered + ignored + failed + delayed
Link: https://lkml.kernel.org/r/20230120034622.2698268-1-jiaqiyan@google.com
Link: https://lkml.kernel.org/r/20230120034622.2698268-2-jiaqiyan@google.com
Signed-off-by: Jiaqi Yan <jiaqiyan@google.com>
Acked-by: David Rientjes <rientjes@google.com>
Acked-by: Naoya Horiguchi <naoya.horiguchi@nec.com>
Cc: Kefeng Wang <wangkefeng.wang@huawei.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Yang Shi <shy828301@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Straightforward conversion of get_hwpoison_huge_page() to
get_hwpoison_hugetlb_folio(). Reduces two references to a head page in
memory-failure.c
[arnd@arndb.de: fix get_hwpoison_hugetlb_folio() stub]
Link: https://lkml.kernel.org/r/20230119111920.635260-1-arnd@kernel.org
Link: https://lkml.kernel.org/r/20230118174039.14247-1-sidhartha.kumar@oracle.com
Signed-off-by: Sidhartha Kumar <sidhartha.kumar@oracle.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Naoya Horiguchi <naoya.horiguchi@nec.com>
Reviewed-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Muchun Song <songmuchun@bytedance.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Use a folio inside unpoison_memory which replaces a compound_head() call
with a call to page_folio().
Link: https://lkml.kernel.org/r/20230112204608.80136-9-sidhartha.kumar@oracle.com
Signed-off-by: Sidhartha Kumar <sidhartha.kumar@oracle.com>
Acked-by: Naoya Horiguchi <naoya.horiguchi@nec.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Miaohe Lin <linmiaohe@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Change hugetlb_set_page_hwpoison() to folio_set_hugetlb_hwpoison() and use
a folio internally.
Link: https://lkml.kernel.org/r/20230112204608.80136-8-sidhartha.kumar@oracle.com
Signed-off-by: Sidhartha Kumar <sidhartha.kumar@oracle.com>
Acked-by: Naoya Horiguchi <naoya.horiguchi@nec.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Miaohe Lin <linmiaohe@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Change __free_raw_hwp_pages() to __folio_free_raw_hwp() and modify its
callers to pass in a folio.
Link: https://lkml.kernel.org/r/20230112204608.80136-7-sidhartha.kumar@oracle.com
Signed-off-by: Sidhartha Kumar <sidhartha.kumar@oracle.com>
Acked-by: Naoya Horiguchi <naoya.horiguchi@nec.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Miaohe Lin <linmiaohe@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Change raw_hwp_list_head() to take in a folio and modify its callers to
pass in a folio. Also converts two users of hugetlb specific page macro
users to their folio equivalents.
Link: https://lkml.kernel.org/r/20230112204608.80136-6-sidhartha.kumar@oracle.com
Signed-off-by: Sidhartha Kumar <sidhartha.kumar@oracle.com>
Acked-by: Naoya Horiguchi <naoya.horiguchi@nec.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Miaohe Lin <linmiaohe@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Change free_raw_hwp_pages() to folio_free_raw_hwp(), converts two users of
hugetlb specific page macro users to their folio equivalents.
Link: https://lkml.kernel.org/r/20230112204608.80136-5-sidhartha.kumar@oracle.com
Signed-off-by: Sidhartha Kumar <sidhartha.kumar@oracle.com>
Acked-by: Naoya Horiguchi <naoya.horiguchi@nec.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Miaohe Lin <linmiaohe@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Change hugetlb_clear_page_hwpoison() to folio_clear_hugetlb_hwpoison() by
changing the function to take in a folio. This converts one use of
ClearPageHWPoison and HPageRawHwpUnreliable to their folio equivalents.
Link: https://lkml.kernel.org/r/20230112204608.80136-4-sidhartha.kumar@oracle.com
Signed-off-by: Sidhartha Kumar <sidhartha.kumar@oracle.com>
Acked-by: Naoya Horiguchi <naoya.horiguchi@nec.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Miaohe Lin <linmiaohe@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Use a struct folio rather than a head page in try_memory_failure_hugetlb.
This converts one user of SetHPageMigratable to the folio equivalent.
Link: https://lkml.kernel.org/r/20230112204608.80136-3-sidhartha.kumar@oracle.com
Signed-off-by: Sidhartha Kumar <sidhartha.kumar@oracle.com>
Acked-by: Naoya Horiguchi <naoya.horiguchi@nec.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Miaohe Lin <linmiaohe@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Patch series "convert hugepage memory failure functions to folios".
This series contains a 1:1 straightforward page to folio conversion for
memory failure functions which deal with huge pages. I renamed a few
functions to fit with how other folio operating functions are named.
These include:
hugetlb_clear_page_hwpoison -> folio_clear_hugetlb_hwpoison
free_raw_hwp_pages -> folio_free_raw_hwp
__free_raw_hwp_pages -> __folio_free_raw_hwp
hugetlb_set_page_hwpoison -> folio_set_hugetlb_hwpoison
The goal of this series was to reduce users of the hugetlb specific page
flag macros which take in a page so users are protected by the compiler to
make sure they are operating on a head page.
This patch (of 8):
Use a folio throughout the function rather than using a head page. This
also reduces the users of the page version of hugetlb specific page flags.
Link: https://lkml.kernel.org/r/20230112204608.80136-2-sidhartha.kumar@oracle.com
Signed-off-by: Sidhartha Kumar <sidhartha.kumar@oracle.com>
Acked-by: Naoya Horiguchi <naoya.horiguchi@nec.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Miaohe Lin <linmiaohe@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Rename tools/vm to tools/mm for being more consistent with the code and
documentation directories, and won't be confused with virtual machines.
Link: https://lkml.kernel.org/r/20230103180754.129637-4-sj@kernel.org
Signed-off-by: SeongJae Park <sj@kernel.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Shuah Khan <shuah@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
If freeit is true, the value of ret must be zero, there is no need to
check the value of freeit after label unlock_mutex.
We can drop variable freeit to do this cleanup.
Link: https://lkml.kernel.org/r/20221125065444.3462681-1-mawupeng1@huawei.com
Signed-off-by: Ma Wupeng <mawupeng1@huawei.com>
Acked-by: Naoya Horiguchi <naoya.horiguchi@nec.com>
Reviewed-by: Miaohe Lin <linmiaohe@huawei.com>
Cc: zhenwei pi <pizhenwei@bytedance.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Replace try_to_release_page() with filemap_release_folio(). This change
is in preparation for the removal of the try_to_release_page() wrapper.
Link: https://lkml.kernel.org/r/20221118073055.55694-4-vishal.moola@gmail.com
Signed-off-by: Vishal Moola (Oracle) <vishal.moola@gmail.com>
Acked-by: Naoya Horiguchi <naoya.horiguchi@nec.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Patch series "mm,huge,rmap: unify and speed up compound mapcounts".
This patch (of 3):
We want to declare one more int in the first tail of a compound page: that
first tail page being valuable property, since every compound page has a
first tail, but perhaps no more than that.
No problem on 64-bit: there is already space for it. No problem with
32-bit THPs: 5.18 commit 5232c63f46 ("mm: Make compound_pincount always
available") kindly cleared the space for it, apparently not realizing that
only 64-bit architectures enable CONFIG_THP_SWAP (whose use of tail
page->private might conflict) - but make sure of that in its Kconfig.
But hugetlb pages use tail page->private of the first tail page for a
subpool pointer, which will conflict; and they also use page->private of
the 2nd, 3rd and 4th tails.
Undo "mm: add private field of first tail to struct page and struct
folio"'s recent addition of private_1 to the folio tail: instead add
hugetlb_subpool, hugetlb_cgroup, hugetlb_cgroup_rsvd, hugetlb_hwpoison to
a second tail page of the folio: THP has long been using several fields of
that tail, so make better use of it for hugetlb too. This is not how a
generic folio should be declared in future, but it is an effective
transitional way to make use of it.
Delete the SUBPAGE_INDEX stuff, but keep __NR_USED_SUBPAGE: now 3.
[hughd@google.com: prefix folio's page_1 and page_2 with double underscore,
give folio's _flags_2 and _head_2 a line documentation each]
Link: https://lkml.kernel.org/r/9e2cb6b-5b58-d3f2-b5ee-5f8a14e8f10@google.com
Link: https://lkml.kernel.org/r/5f52de70-975-e94f-f141-543765736181@google.com
Link: https://lkml.kernel.org/r/3818cc9a-9999-d064-d778-9c94c5911e6@google.com
Signed-off-by: Hugh Dickins <hughd@google.com>
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: James Houghton <jthoughton@google.com>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Miaohe Lin <linmiaohe@huawei.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Mina Almasry <almasrymina@google.com>
Cc: Muchun Song <songmuchun@bytedance.com>
Cc: Naoya Horiguchi <naoya.horiguchi@linux.dev>
Cc: Peter Xu <peterx@redhat.com>
Cc: Sidhartha Kumar <sidhartha.kumar@oracle.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Yang Shi <shy828301@gmail.com>
Cc: Zach O'Keefe <zokeefe@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Currently PageHWPoison flag does not behave well when experiencing memory
hotremove/hotplug. Any data field in struct page is unreliable when the
associated memory is offlined, and the current mechanism can't tell
whether a memory block is onlined because a new memory devices is
installed or because previous failed offline operations are undone.
Especially if there's a hwpoisoned memory, it's unclear what the best
option is.
So introduce a new mechanism to make struct memory_block remember that a
memory block has hwpoisoned memory inside it. And make any online event
fail if the onlining memory block contains hwpoison. struct memory_block
is freed and reallocated over ACPI-based hotremove/hotplug, but not over
sysfs-based hotremove/hotplug. So the new counter can distinguish these
cases.
Link: https://lkml.kernel.org/r/20221024062012.1520887-5-naoya.horiguchi@linux.dev
Signed-off-by: Naoya Horiguchi <naoya.horiguchi@nec.com>
Reported-by: kernel test robot <lkp@intel.com>
Reviewed-by: Miaohe Lin <linmiaohe@huawei.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Jane Chu <jane.chu@oracle.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Muchun Song <songmuchun@bytedance.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Yang Shi <shy828301@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
No functional change.
Link: https://lkml.kernel.org/r/20221024062012.1520887-4-naoya.horiguchi@linux.dev
Signed-off-by: Naoya Horiguchi <naoya.horiguchi@nec.com>
Reviewed-by: Miaohe Lin <linmiaohe@huawei.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Jane Chu <jane.chu@oracle.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Muchun Song <songmuchun@bytedance.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Yang Shi <shy828301@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
These interfaces will be used by drivers/base/memory.c by later patch, so
as a preparatory work move them to more common header file visible to the
file.
Link: https://lkml.kernel.org/r/20221024062012.1520887-3-naoya.horiguchi@linux.dev
Signed-off-by: Naoya Horiguchi <naoya.horiguchi@nec.com>
Reviewed-by: Miaohe Lin <linmiaohe@huawei.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Jane Chu <jane.chu@oracle.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Muchun Song <songmuchun@bytedance.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Yang Shi <shy828301@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Patch series "mm, hwpoison: improve handling workload related to hugetlb
and memory_hotplug", v7.
This patchset tries to solve the issue among memory_hotplug, hugetlb and hwpoison.
In this patchset, memory hotplug handles hwpoison pages like below:
- hwpoison pages should not prevent memory hotremove,
- memory block with hwpoison pages should not be onlined.
This patch (of 4):
HWPoisoned page is not supposed to be accessed once marked, but currently
such accesses can happen during memory hotremove because
do_migrate_range() can be called before dissolve_free_huge_pages() is
called.
Clear HPageMigratable for hwpoisoned hugepages to prevent them from being
migrated. This should be done in hugetlb_lock to avoid race against
isolate_hugetlb().
get_hwpoison_huge_page() needs to have a flag to show it's called from
unpoison to take refcount of hwpoisoned hugepages, so add it.
[naoya.horiguchi@linux.dev: remove TestClearHPageMigratable and reduce to test and clear separately]
Link: https://lkml.kernel.org/r/20221025053559.GA2104800@ik1-406-35019.vs.sakura.ne.jp
Link: https://lkml.kernel.org/r/20221024062012.1520887-1-naoya.horiguchi@linux.dev
Link: https://lkml.kernel.org/r/20221024062012.1520887-2-naoya.horiguchi@linux.dev
Signed-off-by: Naoya Horiguchi <naoya.horiguchi@nec.com>
Reported-by: Miaohe Lin <linmiaohe@huawei.com>
Reviewed-by: Oscar Salvador <osalvador@suse.de>
Reviewed-by: Miaohe Lin <linmiaohe@huawei.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Jane Chu <jane.chu@oracle.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Muchun Song <songmuchun@bytedance.com>
Cc: Yang Shi <shy828301@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Pass pfn/flags to put_ref_page(), then check MF_COUNT_INCREASED and drop
refcount to make the code look cleaner.
Link: https://lkml.kernel.org/r/20221021084611.53765-1-wangkefeng.wang@huawei.com
Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Acked-by: Naoya Horiguchi <naoya.horiguchi@nec.com>
Reviewed-by: Miaohe Lin <linmiaohe@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
This change is very similar to the change that was made for shmem [1], and
it solves the same problem but for HugeTLBFS instead.
Currently, when poison is found in a HugeTLB page, the page is removed
from the page cache. That means that attempting to map or read that
hugepage in the future will result in a new hugepage being allocated
instead of notifying the user that the page was poisoned. As [1] states,
this is effectively memory corruption.
The fix is to leave the page in the page cache. If the user attempts to
use a poisoned HugeTLB page with a syscall, the syscall will fail with
EIO, the same error code that shmem uses. For attempts to map the page,
the thread will get a BUS_MCEERR_AR SIGBUS.
[1]: commit a760542666 ("mm: shmem: don't truncate page if memory failure happens")
Link: https://lkml.kernel.org/r/20221018200125.848471-1-jthoughton@google.com
Signed-off-by: James Houghton <jthoughton@google.com>
Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com>
Reviewed-by: Naoya Horiguchi <naoya.horiguchi@nec.com>
Tested-by: Naoya Horiguchi <naoya.horiguchi@nec.com>
Reviewed-by: Yang Shi <shy828301@gmail.com>
Cc: Axel Rasmussen <axelrasmussen@google.com>
Cc: James Houghton <jthoughton@google.com>
Cc: Miaohe Lin <linmiaohe@huawei.com>
Cc: Muchun Song <songmuchun@bytedance.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
We've got a bunch of special swap entries that stores PFN inside the swap
offset fields. To fetch the PFN, normally the user just calls
swp_offset() assuming that'll be the PFN.
Add a helper swp_offset_pfn() to fetch the PFN instead, fetching only the
max possible length of a PFN on the host, meanwhile doing proper check
with MAX_PHYSMEM_BITS to make sure the swap offsets can actually store the
PFNs properly always using the BUILD_BUG_ON() in is_pfn_swap_entry().
One reason to do so is we never tried to sanitize whether swap offset can
really fit for storing PFN. At the meantime, this patch also prepares us
with the future possibility to store more information inside the swp
offset field, so assuming "swp_offset(entry)" to be the PFN will not stand
any more very soon.
Replace many of the swp_offset() callers to use swp_offset_pfn() where
proper. Note that many of the existing users are not candidates for the
replacement, e.g.:
(1) When the swap entry is not a pfn swap entry at all, or,
(2) when we wanna keep the whole swp_offset but only change the swp type.
For the latter, it can happen when fork() triggered on a write-migration
swap entry pte, we may want to only change the migration type from
write->read but keep the rest, so it's not "fetching PFN" but "changing
swap type only". They're left aside so that when there're more
information within the swp offset they'll be carried over naturally in
those cases.
Since at it, dropping hwpoison_entry_to_pfn() because that's exactly what
the new swp_offset_pfn() is about.
Link: https://lkml.kernel.org/r/20220811161331.37055-4-peterx@redhat.com
Signed-off-by: Peter Xu <peterx@redhat.com>
Reviewed-by: "Huang, Ying" <ying.huang@intel.com>
Cc: Alistair Popple <apopple@nvidia.com>
Cc: Andi Kleen <andi.kleen@intel.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: "Kirill A . Shutemov" <kirill@shutemov.name>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Nadav Amit <nadav.amit@gmail.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Dave Hansen <dave.hansen@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
1.Remove meaningless comment in kill_proc(). That doesn't tell anything.
2.Fix the wrong function name get_hwpoison_unless_zero(). It should be
get_page_unless_zero().
3.The gate keeper for free hwpoison page has moved to check_new_page().
Update the corresponding comment.
Link: https://lkml.kernel.org/r/20220830123604.25763-7-linmiaohe@huawei.com
Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
Acked-by: Naoya Horiguchi <naoya.horiguchi@nec.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
PageTable can't be handled by memory_failure(). Filter it out explicitly in
hwpoison_user_mappings(). This will also make code more consistent with the
relevant check in unpoison_memory().
Link: https://lkml.kernel.org/r/20220830123604.25763-6-linmiaohe@huawei.com
Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
Acked-by: Naoya Horiguchi <naoya.horiguchi@nec.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
If vma->vm_mm != t->mm, there's no need to call page_mapped_in_vma() as
add_to_kill() won't be called in this case. Move up the mm check to avoid
possible unneeded calling to page_mapped_in_vma().
Link: https://lkml.kernel.org/r/20220830123604.25763-5-linmiaohe@huawei.com
Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
Acked-by: Naoya Horiguchi <naoya.horiguchi@nec.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Use num_poisoned_pages_sub() to combine multiple atomic ops into one. Also
num_poisoned_pages_dec() can be killed as there's no caller now.
Link: https://lkml.kernel.org/r/20220830123604.25763-4-linmiaohe@huawei.com
Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
Acked-by: Naoya Horiguchi <naoya.horiguchi@nec.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
It's more recommended to use __PageMovable() to detect non-lru movable
pages. We can avoid bumping page refcnt via isolate_movable_page() for
the isolated lru pages. Also if pages become PageLRU just after they're
checked but before trying to isolate them, isolate_lru_page() will be
called to do the right work.
[linmiaohe@huawei.com: fixes per Naoya Horiguchi]
Link: https://lkml.kernel.org/r/1f7ee86e-7d28-0d8c-e0de-b7a5a94519e8@huawei.com
Link: https://lkml.kernel.org/r/20220830123604.25763-3-linmiaohe@huawei.com
Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
Cc: Naoya Horiguchi <naoya.horiguchi@nec.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Patch series "A few cleanup patches for memory-failure".
his series contains a few cleanup patches to use __PageMovable() to detect
non-lru movable pages, use num_poisoned_pages_sub() to reduce multiple
atomic ops overheads and so on. More details can be found in the
respective changelogs.
This patch (of 6):
Use ClearPageHWPoison() instead of TestClearPageHWPoison() to clear page
hwpoison flags to avoid unneeded full memory barrier overhead.
Link: https://lkml.kernel.org/r/20220830123604.25763-1-linmiaohe@huawei.com
Link: https://lkml.kernel.org/r/20220830123604.25763-2-linmiaohe@huawei.com
Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
Acked-by: Naoya Horiguchi <naoya.horiguchi@nec.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
The GHES code calls memory_failure_queue() from IRQ context to queue work
into workqueue and schedule it on the current CPU. Then the work is
processed in memory_failure_work_func() by kworker and calls
memory_failure().
When a page is already poisoned, commit a3f5d80ea4 ("mm,hwpoison: send
SIGBUS with error virutal address") make memory_failure() call
kill_accessing_process() that:
- holds mmap locking of current->mm
- does pagetable walk to find the error virtual address
- and sends SIGBUS to the current process with error info.
However, the mm of kworker is not valid, resulting in a null-pointer
dereference. So check mm when killing the accessing process.
[akpm@linux-foundation.org: remove unrelated whitespace alteration]
Link: https://lkml.kernel.org/r/20220914064935.7851-1-xueshuai@linux.alibaba.com
Fixes: a3f5d80ea4 ("mm,hwpoison: send SIGBUS with error virutal address")
Signed-off-by: Shuai Xue <xueshuai@linux.alibaba.com>
Reviewed-by: Miaohe Lin <linmiaohe@huawei.com>
Acked-by: Naoya Horiguchi <naoya.horiguchi@nec.com>
Cc: Huang Ying <ying.huang@intel.com>
Cc: Baolin Wang <baolin.wang@linux.alibaba.com>
Cc: Bixuan Cui <cuibixuan@linux.alibaba.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Open-code the page_handle_poison() into soft_offline_page() and kill
unneeded soft_offline_free_page().
Link: https://lkml.kernel.org/r/20220819033402.156519-1-wangkefeng.wang@huawei.com
Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Reviewed-by: Miaohe Lin <linmiaohe@huawei.com>
Acked-by: Naoya Horiguchi <naoya.horiguchi@nec.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
For reserved pages, HWPoison flag will be set without increasing the page
refcnt. So we shouldn't even try to unpoison these pages and thus
decrease the page refcnt unexpectly. Add a PageReserved() check to filter
this case out and remove the below unneeded zero page (zero page is
reserved) check.
Link: https://lkml.kernel.org/r/20220818130016.45313-7-linmiaohe@huawei.com
Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
Acked-by: Naoya Horiguchi <naoya.horiguchi@nec.com>
Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
If try_to_unmap() fails, the hwpoisoned page still resides in the address
space of some processes. We should kill these processes or the hwpoisoned
page might be consumed later. collect_procs() is always called to collect
relevant processes now so they can be killed later if unmap fails.
[linmiaohe@huawei.com: v2]
Link: https://lkml.kernel.org/r/20220823032346.4260-6-linmiaohe@huawei.com
Link: https://lkml.kernel.org/r/20220818130016.45313-6-linmiaohe@huawei.com
Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
Acked-by: Naoya Horiguchi <naoya.horiguchi@nec.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
After kill_procs(), tk will be freed without being removed from the
to_kill list. In the next iteration, the freed list entry in the to_kill
list will be accessed, thus leading to use-after-free issue. Adding
list_del() in kill_procs() to fix the issue.
Link: https://lkml.kernel.org/r/20220823032346.4260-5-linmiaohe@huawei.com
Fixes: c36e202495 ("mm: introduce mf_dax_kill_procs() for fsdax case")
Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
Acked-by: Naoya Horiguchi <naoya.horiguchi@nec.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
When hwpoison_filter() refuses to soft offline a page, the page refcnt
incremented previously by MF_COUNT_INCREASED would have been consumed via
get_hwpoison_page() if ret <= 0. So the put_ref_page() here will put the
extra one. Remove it to fix the issue.
Link: https://lkml.kernel.org/r/20220818130016.45313-4-linmiaohe@huawei.com
Fixes: 9113eaf331 ("mm/memory-failure.c: add hwpoison_filter for soft offline")
Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
Acked-by: Naoya Horiguchi <naoya.horiguchi@nec.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
When free_raw_hwp_pages() fails its work, the refcnt of the hugetlb page
would have been incremented if ret > 0. Using put_page() to fix refcnt
leaking in this case.
Link: https://lkml.kernel.org/r/20220818130016.45313-3-linmiaohe@huawei.com
Fixes: debb6b9c3fdd ("mm, hwpoison: make unpoison aware of raw error info in hwpoisoned hugepage")
Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
Acked-by: Naoya Horiguchi <naoya.horiguchi@nec.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Patch series "A few fixup patches for memory-failure", v2.
This series contains a few fixup patches to fix incorrect update of page
refcnt, fix possible use-after-free issue and so on. More details can be
found in the respective changelogs.
This patch (of 6):
When hwpoison_filter() refuses to hwpoison a hugetlb page, the refcnt of
the page would have been incremented if res == 1. Using put_page() to fix
the refcnt leaking in this case.
Link: https://lkml.kernel.org/r/20220823032346.4260-1-linmiaohe@huawei.com
Link: https://lkml.kernel.org/r/20220818130016.45313-1-linmiaohe@huawei.com
Link: https://lkml.kernel.org/r/20220818130016.45313-2-linmiaohe@huawei.com
Fixes: 405ce05123 ("mm/hwpoison: fix race between hugetlb free/demotion and memory_failure_hugetlb()")
Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
Acked-by: Naoya Horiguchi <naoya.horiguchi@nec.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Since commit 5d1fd5dc87 ("mm,hwpoison: introduce MF_MSG_UNSPLIT_THP"),
the action_result(,MF_MSG_UNSPLIT_THP,) called to show memory error event
in memory_failure(), so the pr_info() in try_to_split_thp_page() is only
needed in soft_offline_in_use_page().
Meanwhile this could also fix the unexpected prefix for "thp split failed"
due to commit 96f96763de ("mm: memory-failure: convert to pr_fmt()").
Link: https://lkml.kernel.org/r/20220809111813.139690-1-wangkefeng.wang@huawei.com
Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Acked-by: Naoya Horiguchi <naoya.horiguchi@nec.com>
Cc: Miaohe Lin <linmiaohe@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
In the case where a filesystem is polled to take over the memory failure
and receives -EOPNOTSUPP it indicates that page->index and page->mapping
are valid for reverse mapping the failure address. Introduce
FSDAX_INVALID_PGOFF to distinguish when add_to_kill() is being called from
mf_dax_kill_procs() by a filesytem vs the typical memory_failure() path.
Otherwise, vma_pgoff_address() is called with an invalid fsdax_pgoff which
then trips this failing signature:
kernel BUG at mm/memory-failure.c:319!
invalid opcode: 0000 [#1] PREEMPT SMP PTI
CPU: 13 PID: 1262 Comm: dax-pmd Tainted: G OE N 6.0.0-rc2+ #62
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 0.0.0 02/06/2015
RIP: 0010:add_to_kill.cold+0x19d/0x209
[..]
Call Trace:
<TASK>
collect_procs.part.0+0x2c4/0x460
memory_failure+0x71b/0xba0
? _printk+0x58/0x73
do_madvise.part.0.cold+0xaf/0xc5
Link: https://lkml.kernel.org/r/166153429427.2758201.14605968329933175594.stgit@dwillia2-xfh.jf.intel.com
Fixes: c36e202495 ("mm: introduce mf_dax_kill_procs() for fsdax case")
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Acked-by: Naoya Horiguchi <naoya.horiguchi@nec.com>
Reviewed-by: Miaohe Lin <linmiaohe@huawei.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Cc: Shiyang Ruan <ruansy.fnst@fujitsu.com>
Cc: Darrick J. Wong <djwong@kernel.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Goldwyn Rodrigues <rgoldwyn@suse.de>
Cc: Jane Chu <jane.chu@oracle.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Ritesh Harjani <riteshh@linux.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Now error handling code is prepared, so remove the blocking code and
enable memory error handling on 1GB hugepage.
Link: https://lkml.kernel.org/r/20220714042420.1847125-9-naoya.horiguchi@linux.dev
Signed-off-by: Naoya Horiguchi <naoya.horiguchi@nec.com>
Reviewed-by: Miaohe Lin <linmiaohe@huawei.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: kernel test robot <lkp@intel.com>
Cc: Liu Shixin <liushixin2@huawei.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Muchun Song <songmuchun@bytedance.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Yang Shi <shy828301@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Currently if memory_failure() (modified to remove blocking code with
subsequent patch) is called on a page in some 1GB hugepage, memory error
handling fails and the raw error page gets into leaked state. The impact
is small in production systems (just leaked single 4kB page), but this
limits the testability because unpoison doesn't work for it. We can no
longer create 1GB hugepage on the 1GB physical address range with such
leaked pages, that's not useful when testing on small systems.
When a hwpoison page in a 1GB hugepage is handled, it's caught by the
PageHWPoison check in free_pages_prepare() because the 1GB hugepage is
broken down into raw error pages before coming to this point:
if (unlikely(PageHWPoison(page)) && !order) {
...
return false;
}
Then, the page is not sent to buddy and the page refcount is left 0.
Originally this check is supposed to work when the error page is freed
from page_handle_poison() (that is called from soft-offline), but now we
are opening another path to call it, so the callers of
__page_handle_poison() need to handle the case by considering the return
value 0 as success. Then page refcount for hwpoison is properly
incremented so unpoison works.
Link: https://lkml.kernel.org/r/20220714042420.1847125-8-naoya.horiguchi@linux.dev
Signed-off-by: Naoya Horiguchi <naoya.horiguchi@nec.com>
Reviewed-by: Miaohe Lin <linmiaohe@huawei.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: kernel test robot <lkp@intel.com>
Cc: Liu Shixin <liushixin2@huawei.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Muchun Song <songmuchun@bytedance.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Yang Shi <shy828301@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
__page_handle_poison() returns bool that shows whether
take_page_off_buddy() has passed or not now. But we will want to
distinguish another case of "dissolve has passed but taking off failed" by
its return value. So change the type of the return value. No functional
change.
Link: https://lkml.kernel.org/r/20220714042420.1847125-7-naoya.horiguchi@linux.dev
Signed-off-by: Naoya Horiguchi <naoya.horiguchi@nec.com>
Reviewed-by: Miaohe Lin <linmiaohe@huawei.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: kernel test robot <lkp@intel.com>
Cc: Liu Shixin <liushixin2@huawei.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Muchun Song <songmuchun@bytedance.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Yang Shi <shy828301@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
If memory_failure() fails to grab page refcount on a hugetlb page because
it's busy, it returns without setting PG_hwpoison on it. This not only
loses a chance of error containment, but breaks the rule that
action_result() should be called only when memory_failure() do any of
handling work (even if that's just setting PG_hwpoison). This
inconsistency could harm code maintainability.
So set PG_hwpoison and call hugetlb_set_page_hwpoison() for such a case.
Link: https://lkml.kernel.org/r/20220714042420.1847125-6-naoya.horiguchi@linux.dev
Fixes: 405ce05123 ("mm/hwpoison: fix race between hugetlb free/demotion and memory_failure_hugetlb()")
Signed-off-by: Naoya Horiguchi <naoya.horiguchi@nec.com>
Reviewed-by: Miaohe Lin <linmiaohe@huawei.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: kernel test robot <lkp@intel.com>
Cc: Liu Shixin <liushixin2@huawei.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Muchun Song <songmuchun@bytedance.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Yang Shi <shy828301@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Raw error info list needs to be removed when hwpoisoned hugetlb is
unpoisoned. And unpoison handler needs to know how many errors there are
in the target hugepage. So add them.
HPageVmemmapOptimized(hpage) and HPageRawHwpUnreliable(hpage)) sometimes
can't be unpoisoned, so skip them.
Link: https://lkml.kernel.org/r/20220714042420.1847125-5-naoya.horiguchi@linux.dev
Signed-off-by: Naoya Horiguchi <naoya.horiguchi@nec.com>
Reported-by: kernel test robot <lkp@intel.com>
Reviewed-by: Miaohe Lin <linmiaohe@huawei.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Liu Shixin <liushixin2@huawei.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Muchun Song <songmuchun@bytedance.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Yang Shi <shy828301@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
