mainline inclusion
from mainline-v5.13
commit ea6d0630
category: bugfix
bugzilla: https://gitee.com/openeuler/intel-kernel/issues/I5HAC1
CVE: NA

Intel_SIG: commit ea6d0630 mm/hwpoison: do not lock page again when me_huge_page() successfully recovers.
Backport for MCA recovery enhancing & bug fix.

--------------------------------

Currently me_huge_page() temporary unlocks page to perform some actions
then locks it again later.  My testcase (which calls hard-offline on
some tail page in a hugetlb, then accesses the address of the hugetlb
range) showed that page allocation code detects this page lock on buddy
page and printed out "BUG: Bad page state" message.

check_new_page_bad() does not consider a page with __PG_HWPOISON as bad
page, so this flag works as kind of filter, but this filtering doesn't
work in this case because the "bad page" is not the actual hwpoisoned
page.  So stop locking page again.  Actions to be taken depend on the
page type of the error, so page unlocking should be done in ->action()
callbacks.  So let's make it assumed and change all existing callbacks
that way.

Link: https://lkml.kernel.org/r/20210609072029.74645-1-nao.horiguchi@gmail.com
Fixes: commit 78bb9203 ("mm: hwpoison: dissolve in-use hugepage in unrecoverable memory error")
Signed-off-by: NNaoya Horiguchi <naoya.horiguchi@nec.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.vnet.ibm.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: NYouquan Song <youquan.song@intel.com>
Signed-off-by: NJason Zeng <jason.zeng@intel.com>