[PATCH v5 0/3] mm,hwpoison: fix sending SIGBUS for Action Required MCE

[Naoya Horiguchi]

I updated the series again with the following changes based on the discussion
over v4:

  - separated v4's 2/2 into two as done in the former version,
  - switched to "first found" approach in getting error virtual address,
    which could report wrong error address to applications but that's rare
    and not critical,
  - rebased onto v5.13-rc2.

v1: https://lore.kernel.org/linux-mm/20210412224320.1747638-1-nao.horiguchi@xxxxxxxxx/T
v2 (only 3/3 is posted): https://lore.kernel.org/linux-mm/20210419023658.GA1962954@u2004/
v3: https://lore.kernel.org/linux-mm/20210421005728.1994268-1-nao.horiguchi@xxxxxxxxx/T
v4: https://lore.kernel.org/linux-mm/20210427062953.2080293-1-nao.horiguchi@xxxxxxxxx/T

Thanks,
Naoya Horiguchi

--- quote from cover letter of v1 ---

I wrote this patchset to materialize what I think is the current
allowable solution mentioned by the previous discussion [1].
I simply borrowed Tony's mutex patch and Aili's return code patch,
then I queued another one to find error virtual address in the best
effort manner.  I know that this is not a perfect solution, but
should work for some typical case.

[1]: https://lore.kernel.org/linux-mm/20210331192540.2141052f@alex-virtual-machine/
---
Summary:

Aili Yao (1):
      mm,hwpoison: Return -EHWPOISON to denote that the page has already been poisoned

Naoya Horiguchi (1):
      mm,hwpoison: Send SIGBUS with error virutal address

Tony Luck (1):
      mm/memory-failure: Use a mutex to avoid memory_failure() races

 arch/x86/kernel/cpu/mce/core.c |  13 ++-
 include/linux/swapops.h        |   5 ++
 mm/memory-failure.c            | 188 ++++++++++++++++++++++++++++++++++++++---
 3 files changed, 190 insertions(+), 16 deletions(-)