From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 4ABC2C43217 for ; Tue, 8 Nov 2022 23:58:23 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230062AbiKHX6U (ORCPT ); Tue, 8 Nov 2022 18:58:20 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:51258 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230032AbiKHX6N (ORCPT ); Tue, 8 Nov 2022 18:58:13 -0500 Received: from ams.source.kernel.org (ams.source.kernel.org [IPv6:2604:1380:4601:e00::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id DC9685EFBF; Tue, 8 Nov 2022 15:58:11 -0800 (PST) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id 91328B81CC7; Tue, 8 Nov 2022 23:58:10 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 39963C433D7; Tue, 8 Nov 2022 23:58:09 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux-foundation.org; s=korg; t=1667951889; bh=E2c2qEBkxnNBZoXaWHL2wa63+cMdHINKCDH1Rv1fK4Q=; h=Date:To:From:Subject:From; b=dLeKeXqUWjJPWW7z8OMHkXVmeFV/vLlg0+yPpRkrequGZM5BKmf9/9r3CnF4VmbSI P3N4mgP4gEkk2AlPMtARqyL9fz/Wo+2+S9pe/n5JIo+DhxQzM396yVex9XgQsrY8mK LUXIxL91KMIx60Fm/rxkYt6QRZwzbN9BB31QELjc= Date: Tue, 08 Nov 2022 15:58:08 -0800 To: mm-commits@vger.kernel.org, stable@vger.kernel.org, songmuchun@bytedance.com, shy828301@gmail.com, naoya.horiguchi@nec.com, mike.kravetz@oracle.com, linmiaohe@huawei.com, axelrasmussen@google.com, jthoughton@google.com, akpm@linux-foundation.org From: Andrew Morton Subject: [merged mm-hotfixes-stable] hugetlbfs-dont-delete-error-page-from-pagecache.patch removed from -mm tree Message-Id: <20221108235809.39963C433D7@smtp.kernel.org> Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org The quilt patch titled Subject: hugetlbfs: don't delete error page from pagecache has been removed from the -mm tree. Its filename was hugetlbfs-dont-delete-error-page-from-pagecache.patch This patch was dropped because it was merged into the mm-hotfixes-stable branch of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm ------------------------------------------------------ From: James Houghton Subject: hugetlbfs: don't delete error page from pagecache Date: Tue, 18 Oct 2022 20:01:25 +0000 This change is very similar to the change that was made for shmem [1], and it solves the same problem but for HugeTLBFS instead. Currently, when poison is found in a HugeTLB page, the page is removed from the page cache. That means that attempting to map or read that hugepage in the future will result in a new hugepage being allocated instead of notifying the user that the page was poisoned. As [1] states, this is effectively memory corruption. The fix is to leave the page in the page cache. If the user attempts to use a poisoned HugeTLB page with a syscall, the syscall will fail with EIO, the same error code that shmem uses. For attempts to map the page, the thread will get a BUS_MCEERR_AR SIGBUS. [1]: commit a76054266661 ("mm: shmem: don't truncate page if memory failure happens") Link: https://lkml.kernel.org/r/20221018200125.848471-1-jthoughton@google.com Signed-off-by: James Houghton Reviewed-by: Mike Kravetz Reviewed-by: Naoya Horiguchi Tested-by: Naoya Horiguchi Reviewed-by: Yang Shi Cc: Axel Rasmussen Cc: James Houghton Cc: Miaohe Lin Cc: Muchun Song Cc: Signed-off-by: Andrew Morton --- fs/hugetlbfs/inode.c | 13 ++++++------- mm/hugetlb.c | 4 ++++ mm/memory-failure.c | 5 ++++- 3 files changed, 14 insertions(+), 8 deletions(-) --- a/fs/hugetlbfs/inode.c~hugetlbfs-dont-delete-error-page-from-pagecache +++ a/fs/hugetlbfs/inode.c @@ -328,6 +328,12 @@ static ssize_t hugetlbfs_read_iter(struc } else { unlock_page(page); + if (PageHWPoison(page)) { + put_page(page); + retval = -EIO; + break; + } + /* * We have the page, copy it to user space buffer. */ @@ -1111,13 +1117,6 @@ static int hugetlbfs_migrate_folio(struc static int hugetlbfs_error_remove_page(struct address_space *mapping, struct page *page) { - struct inode *inode = mapping->host; - pgoff_t index = page->index; - - hugetlb_delete_from_page_cache(page); - if (unlikely(hugetlb_unreserve_pages(inode, index, index + 1, 1))) - hugetlb_fix_reserve_counts(inode); - return 0; } --- a/mm/hugetlb.c~hugetlbfs-dont-delete-error-page-from-pagecache +++ a/mm/hugetlb.c @@ -6111,6 +6111,10 @@ int hugetlb_mcopy_atomic_pte(struct mm_s ptl = huge_pte_lock(h, dst_mm, dst_pte); + ret = -EIO; + if (PageHWPoison(page)) + goto out_release_unlock; + /* * We allow to overwrite a pte marker: consider when both MISSING|WP * registered, we firstly wr-protect a none pte which has no page cache --- a/mm/memory-failure.c~hugetlbfs-dont-delete-error-page-from-pagecache +++ a/mm/memory-failure.c @@ -1080,6 +1080,7 @@ static int me_huge_page(struct page_stat int res; struct page *hpage = compound_head(p); struct address_space *mapping; + bool extra_pins = false; if (!PageHuge(hpage)) return MF_DELAYED; @@ -1087,6 +1088,8 @@ static int me_huge_page(struct page_stat mapping = page_mapping(hpage); if (mapping) { res = truncate_error_page(hpage, page_to_pfn(p), mapping); + /* The page is kept in page cache. */ + extra_pins = true; unlock_page(hpage); } else { unlock_page(hpage); @@ -1104,7 +1107,7 @@ static int me_huge_page(struct page_stat } } - if (has_extra_refcount(ps, p, false)) + if (has_extra_refcount(ps, p, extra_pins)) res = MF_FAILED; return res; _ Patches currently in -mm which might be from jthoughton@google.com are