Hi Greg, On Fri, Apr 01, 2022 at 03:33:48PM +0200, gregkh@xxxxxxxxxxxxxxxxxxx wrote: > > The patch below does not apply to the 4.14-stable tree. > If someone wants it applied there, or to any other stable or longterm > tree, then please email the backport, including the original git commit > id to <stable@xxxxxxxxxxxxxxx>. Here is the backport. -- Regards Sudip
>From c28271b2a06bf66bdbde09481ffb500387a50238 Mon Sep 17 00:00:00 2001 From: Rik van Riel <riel@xxxxxxxxxxx> Date: Tue, 22 Mar 2022 14:44:09 -0700 Subject: [PATCH] mm: invalidate hwpoison page cache page in fault path commit e53ac7374e64dede04d745ff0e70ff5048378d1f upstream. 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@xxxxxxxxxxxxxxxxxxxx Signed-off-by: Rik van Riel <riel@xxxxxxxxxxx> Reviewed-by: Miaohe Lin <linmiaohe@xxxxxxxxxx> Acked-by: Naoya Horiguchi <naoya.horiguchi@xxxxxxx> Reviewed-by: Oscar Salvador <osalvador@xxxxxxx> Cc: John Hubbard <jhubbard@xxxxxxxxxx> Cc: Mel Gorman <mgorman@xxxxxxx> Cc: Johannes Weiner <hannes@xxxxxxxxxxx> Cc: Matthew Wilcox <willy@xxxxxxxxxxxxx> Cc: <stable@xxxxxxxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> Signed-off-by: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx> [sudip: use int instead of vm_fault_t] Signed-off-by: Sudip Mukherjee <sudipm.mukherjee@xxxxxxxxx> --- mm/memory.c | 9 +++++++-- 1 file changed, 7 insertions(+), 2 deletions(-) diff --git a/mm/memory.c b/mm/memory.c index 4154fb45ac0f7..615cb3fe763dd 100644 --- a/mm/memory.c +++ b/mm/memory.c @@ -3342,11 +3342,16 @@ static int __do_fault(struct vm_fault *vmf) return ret; if (unlikely(PageHWPoison(vmf->page))) { - if (ret & VM_FAULT_LOCKED) + int poisonret = VM_FAULT_HWPOISON; + if (ret & VM_FAULT_LOCKED) { + /* Retry if a clean page was removed from the cache. */ + if (invalidate_inode_page(vmf->page)) + poisonret = 0; unlock_page(vmf->page); + } put_page(vmf->page); vmf->page = NULL; - return VM_FAULT_HWPOISON; + return poisonret; } if (unlikely(!(ret & VM_FAULT_LOCKED))) -- 2.30.2
