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Jiaqi Yan 12904d9533 mm/khugepaged: recover from poisoned file-backed memory
Make collapse_file roll back when copying pages failed. More concretely:
- extract copying operations into a separate loop
- postpone the updates for nr_none until both scanning and copying
  succeeded
- postpone joining small xarray entries until both scanning and copying
  succeeded
- postpone the update operations to NR_XXX_THPS until both scanning and
  copying succeeded
- for non-SHMEM file, roll back filemap_nr_thps_inc if scan succeeded but
  copying failed

Tested manually:
0. Enable khugepaged on system under test. Mount tmpfs at /mnt/ramdisk.
1. Start a two-thread application. Each thread allocates a chunk of
   non-huge memory buffer from /mnt/ramdisk.
2. Pick 4 random buffer address (2 in each thread) and inject
   uncorrectable memory errors at physical addresses.
3. Signal both threads to make their memory buffer collapsible, i.e.
   calling madvise(MADV_HUGEPAGE).
4. Wait and then check kernel log: khugepaged is able to recover from
   poisoned pages by skipping them.
5. Signal both threads to inspect their buffer contents and make sure no
   data corruption.

Link: https://lkml.kernel.org/r/20230329151121.949896-4-jiaqiyan@google.com
Signed-off-by: Jiaqi Yan <jiaqiyan@google.com>
Reviewed-by: Yang Shi <shy828301@gmail.com>
Acked-by: Hugh Dickins <hughd@google.com>
Cc: David Stevens <stevensd@chromium.org>
Cc: Kefeng Wang <wangkefeng.wang@huawei.com>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: "Kirill A. Shutemov" <kirill@shutemov.name>
Cc: Miaohe Lin <linmiaohe@huawei.com>
Cc: Naoya Horiguchi <naoya.horiguchi@nec.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Tong Tiangen <tongtiangen@huawei.com>
Cc: Tony Luck <tony.luck@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-04-18 16:29:51 -07:00
arch xtensa: reword ARCH_FORCE_MAX_ORDER prompt and help text 2023-04-18 16:29:46 -07:00
block block: remove obsolete config BLOCK_COMPAT 2023-03-16 09:35:44 -06:00
certs Kbuild updates for v6.3 2023-02-26 11:53:25 -08:00
crypto asymmetric_keys: log on fatal failures in PE/pkcs7 2023-03-21 16:23:56 +00:00
Documentation sync mm-stable with mm-hotfixes-stable to pick up depended-upon upstream changes 2023-04-16 12:31:58 -07:00
drivers drm/ttm: remove comment referencing now-removed vmf_insert_mixed_prot() 2023-04-05 19:42:56 -07:00
fs sync mm-stable with mm-hotfixes-stable to pick up depended-upon upstream changes 2023-04-18 14:53:49 -07:00
include mm/hwpoison: introduce copy_mc_highpage 2023-04-18 16:29:51 -07:00
init init,mm: fold late call to page_ext_init() to page_alloc_init_late() 2023-04-05 19:42:54 -07:00
io_uring block-6.3-2023-03-24 2023-03-24 14:10:39 -07:00
ipc Merge branch 'work.namespace' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2023-02-24 19:20:07 -08:00
kernel cgroup: rename cgroup_rstat_flush_"irqsafe" to "atomic" 2023-04-18 16:29:49 -07:00
lib lib/test_vmalloc.c: add vm_map_ram()/vm_unmap_ram() test case 2023-04-18 16:29:47 -07:00
LICENSES LICENSES: Add the copyleft-next-0.3.1 license 2022-11-08 15:44:01 +01:00
mm mm/khugepaged: recover from poisoned file-backed memory 2023-04-18 16:29:51 -07:00
net mm, treewide: redefine MAX_ORDER sanely 2023-04-05 19:42:46 -07:00
rust Rust fixes for 6.3-rc1 2023-03-03 14:51:15 -08:00
samples kmemleak-test: fix kmemleak_test.c build logic 2023-04-18 16:29:47 -07:00
scripts kasan: remove hwasan-kernel-mem-intrinsic-prefix=1 for clang-14 2023-04-18 16:29:43 -07:00
security mm, treewide: redefine MAX_ORDER sanely 2023-04-05 19:42:46 -07:00
sound ALSA: hda/ca0132: fixup buffer overrun at tuning_ctl_set() 2023-03-14 17:04:53 +01:00
tools sync mm-stable with mm-hotfixes-stable to pick up depended-upon upstream changes 2023-04-18 14:53:49 -07:00
usr usr/gen_init_cpio.c: remove unnecessary -1 values from int file 2022-10-03 14:21:44 -07:00
virt KVM/riscv changes for 6.3 2023-02-15 12:33:28 -05:00
.clang-format cpumask: re-introduce constant-sized cpumask optimizations 2023-03-05 14:30:34 -08:00
.cocciconfig
.get_maintainer.ignore
.gitattributes .gitattributes: use 'dts' diff driver for *.dtso files 2023-02-26 15:28:23 +09:00
.gitignore kbuild: rpm-pkg: move source components to rpmbuild/SOURCES 2023-03-16 22:45:56 +09:00
.mailmap mailmap: update jtoppins' entry to reference correct email 2023-04-16 10:41:25 -07:00
.rustfmt.toml
COPYING
CREDITS There is no particular theme here - mainly quick hits all over the tree. 2023-02-23 17:55:40 -08:00
Kbuild Kbuild updates for v6.1 2022-10-10 12:00:45 -07:00
Kconfig
MAINTAINERS MAINTAINERS: extend memblock entry to include MM initialization 2023-04-05 19:42:55 -07:00
Makefile Linux 6.3-rc4 2023-03-26 14:40:20 -07:00
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