@@ -3918,14 +3918,18 @@ static vm_fault_t __do_fault(struct vm_f
return ret;
if (unlikely(PageHWPoison(vmf->page))) {
+ struct page *page = vmf->page;
vm_fault_t poisonret = VM_FAULT_HWPOISON;
if (ret & VM_FAULT_LOCKED) {
+ if (page_mapped(page))
+ unmap_mapping_pages(page_mapping(page),
+ page->index, 1, false);
/* Retry if a clean page was removed from the cache. */
- if (invalidate_inode_page(vmf->page))
- poisonret = 0;
- unlock_page(vmf->page);
+ if (invalidate_inode_page(page))
+ poisonret = VM_FAULT_NOPAGE;
+ unlock_page(page);
}
- put_page(vmf->page);
+ put_page(page);
vmf->page = NULL;
return poisonret;
}
The patch titled Subject: mm,hwpoison: unmap poisoned page before invalidation has been added to the -mm tree. Its filename is mmhwpoison-unmap-poisoned-page-before-invalidation.patch This patch should soon appear at https://ozlabs.org/~akpm/mmots/broken-out/mmhwpoison-unmap-poisoned-page-before-invalidation.patch and later at https://ozlabs.org/~akpm/mmotm/broken-out/mmhwpoison-unmap-poisoned-page-before-invalidation.patch Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/process/submit-checklist.rst when testing your code *** The -mm tree is included into linux-next and is updated there every 3-4 working days ------------------------------------------------------ From: Rik van Riel <riel@surriel.com> Subject: mm,hwpoison: unmap poisoned page before invalidation In some cases it appears the invalidation of a hwpoisoned page fails because the page is still mapped in another process. This can cause a program to be continuously restarted and die when it page faults on the page that was not invalidated. Avoid that problem by unmapping the hwpoisoned page when we find it. Another issue is that sometimes we end up oopsing in finish_fault, if the code tries to do something with the now-NULL vmf->page. I did not hit this error when submitting the previous patch because there are several opportunities for alloc_set_pte to bail out before accessing vmf->page, and that apparently happened on those systems, and most of the time on other systems, too. However, across several million systems that error does occur a handful of times a day. It can be avoided by returning VM_FAULT_NOPAGE which will cause do_read_fault to return before calling finish_fault. Link: https://lkml.kernel.org/r/20220325161428.5068d97e@imladris.surriel.com Fixes: e53ac7374e64 ("mm: invalidate hwpoison page cache page in fault path") Reviewed-by: Miaohe Lin <linmiaohe@huawei.com> Tested-by: Naoya Horiguchi <naoya.horiguchi@nec.com> Cc: Oscar Salvador <osalvador@suse.de> Cc: Mel Gorman <mgorman@suse.de> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> --- mm/memory.c | 12 ++++++++---- 1 file changed, 8 insertions(+), 4 deletions(-)