mm: invalidate hwpoison page cache page in fault path
authorRik van Riel <riel@surriel.com>
Mon, 28 Feb 2022 23:01:06 +0000 (10:01 +1100)
committerStephen Rothwell <sfr@canb.auug.org.au>
Mon, 28 Feb 2022 23:01:06 +0000 (10:01 +1100)
commit65b23b9d141db2aec46c4beba0bf81c6e77881da
tree6439194fa7546fe1c34a5110d1ac7163661c0094
parent25ee0bcaa9ec22d1e13ed277e0b61a377f3b8b05
mm: invalidate hwpoison page cache page in fault path

Sometimes the page offlining code can leave behind a hwpoisoned clean page
cache page.  This can lead to programs being killed over and over and over
again as they fault in the hwpoisoned page, get killed, and then get
re-spawned by whatever wanted to run them.

This is particularly embarrassing when the page was offlined due to having
too many corrected memory errors.  Now we are killing tasks due to them
trying to access memory that probably isn't even corrupted.

This problem can be avoided by invalidating the page from the page fault
handler, which already has a branch for dealing with these kinds of pages.
With this patch we simply pretend the page fault was successful if the
page was invalidated, return to userspace, incur another page fault, read
in the file from disk (to a new memory page), and then everything works
again.

Link: https://lkml.kernel.org/r/20220212213740.423efcea@imladris.surriel.com
Signed-off-by: Rik van Riel <riel@surriel.com>
Reviewed-by: Miaohe Lin <linmiaohe@huawei.com>
Acked-by: Naoya Horiguchi <naoya.horiguchi@nec.com>
Reviewed-by: Oscar Salvador <osalvador@suse.de>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
mm/memory.c