From patchwork Thu Nov 4 21:07:51 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Yang Shi X-Patchwork-Id: 12603801 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 mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 683CAC4332F for ; Thu, 4 Nov 2021 21:07:58 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id E28566124A for ; Thu, 4 Nov 2021 21:07:57 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org E28566124A Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=gmail.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=kvack.org Received: by kanga.kvack.org (Postfix) id 18EBE6B0071; Thu, 4 Nov 2021 17:07:57 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 116F0940007; Thu, 4 Nov 2021 17:07:57 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id F204E6B0073; Thu, 4 Nov 2021 17:07:56 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0234.hostedemail.com [216.40.44.234]) by kanga.kvack.org (Postfix) with ESMTP id E19596B0071 for ; Thu, 4 Nov 2021 17:07:56 -0400 (EDT) Received: from smtpin04.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay05.hostedemail.com (Postfix) with ESMTP id 8EC51184EA70F for ; Thu, 4 Nov 2021 21:07:56 +0000 (UTC) X-FDA: 78772484952.04.F15710C Received: from mail-pf1-f174.google.com (mail-pf1-f174.google.com [209.85.210.174]) by imf15.hostedemail.com (Postfix) with ESMTP id AE51BD0000A4 for ; Thu, 4 Nov 2021 21:07:45 +0000 (UTC) Received: by mail-pf1-f174.google.com with SMTP id g18so2238511pfk.5 for ; Thu, 04 Nov 2021 14:07:56 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=9BiJt54qFZ/VuFOPoUw2HvY4OErYWaH/g0QELRHYaEM=; b=JR2B77A7w9AxNwZiwRneH3U+LDgO7FF6to59gQG7raqqjhoqQaITMu1qzPmDRxdQ1e HkM5PZsZZjGaSa5A4x03k5PzwVqNfTluN5kCPt/LHWA/+bnTDiLKzoutgfmfRiOO7OBi 3779F30Gzg9jNMvKNqo7IDTzrryKU/Wb4nxdSMkuW7Ga2wQAAMxb5mrowJtGyuEtiXqs 32kh0w+PYo/X9QHiehvQ5HNlxhCZWNo3HJntQsU+49r7PWh4LRpPFlMCKEsyR5cz4/v8 aLX5xkCun5dKl184rAsaLUawLTit6+7yG8rhTwRn26uqCAKeFkyMaPKad7jMSi4ntbw9 Ulng== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=9BiJt54qFZ/VuFOPoUw2HvY4OErYWaH/g0QELRHYaEM=; b=akvIJQTqRs6DTpSvxS/F9haIklDdoCwy2PNGgVcLE9+fH8JQZArU1NAW7l7qZdExUH FlAL8QNISMF0x4rb9y4PvDrcLQVMsU97ExmbppcNFTX1uWHdc/X0W2Ab74Lb2q1N2G/I xKQZfsy5nX8ByrAPeZuDiA+yYS9+I11gnpuIEuG8XMhtqIw/+gZ8zYRDzelww0SOBPlI zKXINuPukYaxHLI6XxNnceXNi0HUYQlDEE6HGVQyn/jYLvOWfu7dSLnK21Iuzrfo6Mbg vMkzk0pO0/eK22iE3/pYA2noKGqlyOKdTzNliaWXWPy/5SPxgj3m1ZcWqP87TQQXqzbz r3jw== X-Gm-Message-State: AOAM5303s2ipdA+YJVR7g3B7kK4eqmYi75Jyj6KTHn6jMnsbclo+soMx uKY/vRTPQf7fMu5euMi1mnQ= X-Google-Smtp-Source: ABdhPJzL5YjCBbrnkOB2UCcpqKtJy28zI2Io3AbzarVO6TBw75pVAsBTv/HqC8QT0vlEL6Drk+j7sw== X-Received: by 2002:a65:4bca:: with SMTP id p10mr26097982pgr.391.1636060075178; Thu, 04 Nov 2021 14:07:55 -0700 (PDT) Received: from localhost.localdomain (c-73-93-239-127.hsd1.ca.comcast.net. [73.93.239.127]) by smtp.gmail.com with ESMTPSA id s69sm4523688pgc.43.2021.11.04.14.07.53 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 04 Nov 2021 14:07:54 -0700 (PDT) From: Yang Shi To: gregkh@linuxfoundation.org, naoya.horiguchi@nec.com, hughd@google.com, kirill.shutemov@linux.intel.com, willy@infradead.org, osalvador@suse.de, peterx@redhat.com, akpm@linux-foundation.org Cc: shy828301@gmail.com, stable@vger.kernel.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: [stable 5.10 v2 PATCH 1/2] mm: hwpoison: remove the unnecessary THP check Date: Thu, 4 Nov 2021 14:07:51 -0700 Message-Id: <20211104210752.390351-1-shy828301@gmail.com> X-Mailer: git-send-email 2.26.2 MIME-Version: 1.0 Authentication-Results: imf15.hostedemail.com; dkim=pass header.d=gmail.com header.s=20210112 header.b=JR2B77A7; dmarc=pass (policy=none) header.from=gmail.com; spf=pass (imf15.hostedemail.com: domain of shy828301@gmail.com designates 209.85.210.174 as permitted sender) smtp.mailfrom=shy828301@gmail.com X-Rspamd-Server: rspam04 X-Rspamd-Queue-Id: AE51BD0000A4 X-Stat-Signature: ypssozwsohgdwoa8m39krkik5nesau1i X-HE-Tag: 1636060065-442800 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: commit c7cb42e94473aafe553c0f2a3d8ca904599399ed upstream. When handling THP hwpoison checked if the THP is in allocation or free stage since hwpoison may mistreat it as hugetlb page. After commit 415c64c1453a ("mm/memory-failure: split thp earlier in memory error handling") the problem has been fixed, so this check is no longer needed. Remove it. The side effect of the removal is hwpoison may report unsplit THP instead of unknown error for shmem THP. It seems not like a big deal. The following patch "mm: filemap: check if THP has hwpoisoned subpage for PMD page fault" depends on this, which fixes shmem THP with hwpoisoned subpage(s) are mapped PMD wrongly. So this patch needs to be backported to -stable as well. Link: https://lkml.kernel.org/r/20211020210755.23964-2-shy828301@gmail.com Signed-off-by: Yang Shi Suggested-by: Naoya Horiguchi Acked-by: Naoya Horiguchi Cc: Hugh Dickins Cc: Kirill A. Shutemov Cc: Matthew Wilcox Cc: Oscar Salvador Cc: Peter Xu Cc: Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- mm/memory-failure.c | 14 -------------- 1 file changed, 14 deletions(-) diff --git a/mm/memory-failure.c b/mm/memory-failure.c index 01445ddff58d..bd2cd4dd59b6 100644 --- a/mm/memory-failure.c +++ b/mm/memory-failure.c @@ -956,20 +956,6 @@ static int get_hwpoison_page(struct page *page) { struct page *head = compound_head(page); - if (!PageHuge(head) && PageTransHuge(head)) { - /* - * Non anonymous thp exists only in allocation/free time. We - * can't handle such a case correctly, so let's give it up. - * This should be better than triggering BUG_ON when kernel - * tries to touch the "partially handled" page. - */ - if (!PageAnon(head)) { - pr_err("Memory failure: %#lx: non anonymous thp\n", - page_to_pfn(page)); - return 0; - } - } - if (get_page_unless_zero(head)) { if (head == compound_head(page)) return 1; From patchwork Thu Nov 4 21:07:52 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Yang Shi X-Patchwork-Id: 12603803 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 mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id B22F6C433F5 for ; Thu, 4 Nov 2021 21:07:59 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 6B8E761106 for ; Thu, 4 Nov 2021 21:07:59 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org 6B8E761106 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=gmail.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=kvack.org Received: by kanga.kvack.org (Postfix) id EFB5C940008; Thu, 4 Nov 2021 17:07:58 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id E84E3940007; Thu, 4 Nov 2021 17:07:58 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id CB06C940008; Thu, 4 Nov 2021 17:07:58 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0057.hostedemail.com [216.40.44.57]) by kanga.kvack.org (Postfix) with ESMTP id B40DC940007 for ; Thu, 4 Nov 2021 17:07:58 -0400 (EDT) Received: from smtpin27.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay03.hostedemail.com (Postfix) with ESMTP id 609748249980 for ; Thu, 4 Nov 2021 21:07:58 +0000 (UTC) X-FDA: 78772485036.27.34C2E52 Received: from mail-pl1-f179.google.com (mail-pl1-f179.google.com [209.85.214.179]) by imf29.hostedemail.com (Postfix) with ESMTP id F3DFD9000254 for ; Thu, 4 Nov 2021 21:07:57 +0000 (UTC) Received: by mail-pl1-f179.google.com with SMTP id u17so9344677plg.9 for ; Thu, 04 Nov 2021 14:07:57 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=oxDXlFZv18SaVr7yVerydN4wv6+UR/Mko0Frp1wGsZI=; b=iMwewlmHpZlJFiy8dVLPT/9iXgNfMmxF00y8jqrPWIt0QjHkw7YoV0Qic1QC11Db4i QhS6LtFsd4CaiTteQrB7OIxgGoTBMgH3Y6aqAaE1A+SmuipRVaF/pTA4/p+CNGbKd+dd my/t5L4VYX7jpM/+bgjTcQ5rWu8dy76ougyqfVMqH55bF0p4RXLxqq9E8UnIEWxE1Bbt zpNb2NjDHX/hN/TD6GfWuGULscy6W2/VQmym/A3UlsVgVfJWQxKVOzxqVkcG4AfAyLUu qHdQmiJnjQZMEG0iMxU6QSqFgMvBmKHBmHsmRl0HcIsvEPgLhJFGrv1s1TOzxumFkBvG nrrw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=oxDXlFZv18SaVr7yVerydN4wv6+UR/Mko0Frp1wGsZI=; b=2GIeYVwjCP+h7CnSFXh+03edlcsrBC/RiA1mP1l7MApwNsuMVwDraQZaMVUiWO+gD0 dED1Xm2AvAYYdeeNG38yZlUi3bGtFVSPrti64XJYbJ4+Vw870alDcr51ktXBiduITJZa l5fIVzmUl4eC3RCgtyGd4x+swxoK+Wxb1ltOqxU5nxJ6JzBpLF42v2COy2oUW/mNwUjn hWrIMha4IGXY8DvHJ/mb39+CKmAf9zbrooQAiBEjrWPu96gm8cI94V8mXJ3vKBWd8PCi l/vC+6fhSR23lwS0qJuLLCIS8DWuuijUBUt2tMiOLwiWoLVjjQZUbC1nTSDsyW0/iioc EWDw== X-Gm-Message-State: AOAM530cKBLv8k+pgXeqB9PA7OawAkyBk/DY7bD5txBaWjs2rNzca9vr t7++Tu2gVcrQXSpip45x3Bn7WeP/vPc= X-Google-Smtp-Source: ABdhPJzCizhyL/NVth/pWVE9GnmOZclcspfIp5ZqA/5hPzCK9sW0rwa+eYW7fmCn1R78Bzmxg30ffg== X-Received: by 2002:a17:90a:4212:: with SMTP id o18mr16378748pjg.154.1636060077070; Thu, 04 Nov 2021 14:07:57 -0700 (PDT) Received: from localhost.localdomain (c-73-93-239-127.hsd1.ca.comcast.net. [73.93.239.127]) by smtp.gmail.com with ESMTPSA id s69sm4523688pgc.43.2021.11.04.14.07.55 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 04 Nov 2021 14:07:56 -0700 (PDT) From: Yang Shi To: gregkh@linuxfoundation.org, naoya.horiguchi@nec.com, hughd@google.com, kirill.shutemov@linux.intel.com, willy@infradead.org, osalvador@suse.de, peterx@redhat.com, akpm@linux-foundation.org Cc: shy828301@gmail.com, stable@vger.kernel.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: [stable 5.10 v2 PATCH 2/2] mm: filemap: check if THP has hwpoisoned subpage for PMD page fault Date: Thu, 4 Nov 2021 14:07:52 -0700 Message-Id: <20211104210752.390351-2-shy828301@gmail.com> X-Mailer: git-send-email 2.26.2 In-Reply-To: <20211104210752.390351-1-shy828301@gmail.com> References: <20211104210752.390351-1-shy828301@gmail.com> MIME-Version: 1.0 X-Rspamd-Server: rspam05 X-Rspamd-Queue-Id: F3DFD9000254 X-Stat-Signature: umhmyzbyqhq3zg3ts1z4s4ehm7yufenf Authentication-Results: imf29.hostedemail.com; dkim=pass header.d=gmail.com header.s=20210112 header.b=iMwewlmH; spf=pass (imf29.hostedemail.com: domain of shy828301@gmail.com designates 209.85.214.179 as permitted sender) smtp.mailfrom=shy828301@gmail.com; dmarc=pass (policy=none) header.from=gmail.com X-HE-Tag: 1636060077-208629 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: commit eac96c3efdb593df1a57bb5b95dbe037bfa9a522 upstream. When handling shmem page fault the THP with corrupted subpage could be PMD mapped if certain conditions are satisfied. But kernel is supposed to send SIGBUS when trying to map hwpoisoned page. There are two paths which may do PMD map: fault around and regular fault. Before commit f9ce0be71d1f ("mm: Cleanup faultaround and finish_fault() codepaths") the thing was even worse in fault around path. The THP could be PMD mapped as long as the VMA fits regardless what subpage is accessed and corrupted. After this commit as long as head page is not corrupted the THP could be PMD mapped. In the regular fault path the THP could be PMD mapped as long as the corrupted page is not accessed and the VMA fits. This loophole could be fixed by iterating every subpage to check if any of them is hwpoisoned or not, but it is somewhat costly in page fault path. So introduce a new page flag called HasHWPoisoned on the first tail page. It indicates the THP has hwpoisoned subpage(s). It is set if any subpage of THP is found hwpoisoned by memory failure and after the refcount is bumped successfully, then cleared when the THP is freed or split. The soft offline path doesn't need this since soft offline handler just marks a subpage hwpoisoned when the subpage is migrated successfully. But shmem THP didn't get split then migrated at all. Link: https://lkml.kernel.org/r/20211020210755.23964-3-shy828301@gmail.com Fixes: 800d8c63b2e9 ("shmem: add huge pages support") Signed-off-by: Yang Shi Reviewed-by: Naoya Horiguchi Suggested-by: Kirill A. Shutemov Cc: Hugh Dickins Cc: Matthew Wilcox Cc: Oscar Salvador Cc: Peter Xu Cc: Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- Fixed build failure on stable tree. include/linux/page-flags.h | 23 +++++++++++++++++++++++ mm/huge_memory.c | 2 ++ mm/memory-failure.c | 14 ++++++++++++++ mm/memory.c | 9 +++++++++ mm/page_alloc.c | 4 +++- 5 files changed, 51 insertions(+), 1 deletion(-) diff --git a/include/linux/page-flags.h b/include/linux/page-flags.h index 4f6ba9379112..1e33ba465195 100644 --- a/include/linux/page-flags.h +++ b/include/linux/page-flags.h @@ -169,6 +169,15 @@ enum pageflags { /* Compound pages. Stored in first tail page's flags */ PG_double_map = PG_workingset, +#ifdef CONFIG_MEMORY_FAILURE + /* + * Compound pages. Stored in first tail page's flags. + * Indicates that at least one subpage is hwpoisoned in the + * THP. + */ + PG_has_hwpoisoned = PG_mappedtodisk, +#endif + /* non-lru isolated movable page */ PG_isolated = PG_reclaim, @@ -701,6 +710,20 @@ PAGEFLAG_FALSE(DoubleMap) TESTSCFLAG_FALSE(DoubleMap) #endif +#if defined(CONFIG_MEMORY_FAILURE) && defined(CONFIG_TRANSPARENT_HUGEPAGE) +/* + * PageHasHWPoisoned indicates that at least one subpage is hwpoisoned in the + * compound page. + * + * This flag is set by hwpoison handler. Cleared by THP split or free page. + */ +PAGEFLAG(HasHWPoisoned, has_hwpoisoned, PF_SECOND) + TESTSCFLAG(HasHWPoisoned, has_hwpoisoned, PF_SECOND) +#else +PAGEFLAG_FALSE(HasHWPoisoned) + TESTSCFLAG_FALSE(HasHWPoisoned) +#endif + /* * For pages that are never mapped to userspace (and aren't PageSlab), * page_type may be used. Because it is initialised to -1, we invert the diff --git a/mm/huge_memory.c b/mm/huge_memory.c index 594368f6134f..8cf6b2dc5332 100644 --- a/mm/huge_memory.c +++ b/mm/huge_memory.c @@ -2464,6 +2464,8 @@ static void __split_huge_page(struct page *page, struct list_head *list, xa_lock(&swap_cache->i_pages); } + ClearPageHasHWPoisoned(head); + for (i = nr - 1; i >= 1; i--) { __split_huge_page_tail(head, i, lruvec, list); /* Some pages can be beyond i_size: drop them from page cache */ diff --git a/mm/memory-failure.c b/mm/memory-failure.c index bd2cd4dd59b6..d76743d9d760 100644 --- a/mm/memory-failure.c +++ b/mm/memory-failure.c @@ -1367,6 +1367,20 @@ int memory_failure(unsigned long pfn, int flags) } if (PageTransHuge(hpage)) { + /* + * The flag must be set after the refcount is bumped + * otherwise it may race with THP split. + * And the flag can't be set in get_hwpoison_page() since + * it is called by soft offline too and it is just called + * for !MF_COUNT_INCREASE. So here seems to be the best + * place. + * + * Don't need care about the above error handling paths for + * get_hwpoison_page() since they handle either free page + * or unhandlable page. The refcount is bumped iff the + * page is a valid handlable page. + */ + SetPageHasHWPoisoned(hpage); if (try_to_split_thp_page(p, "Memory Failure") < 0) { action_result(pfn, MF_MSG_UNSPLIT_THP, MF_IGNORED); return -EBUSY; diff --git a/mm/memory.c b/mm/memory.c index 4fe24cd865a7..bc3063351620 100644 --- a/mm/memory.c +++ b/mm/memory.c @@ -3920,6 +3920,15 @@ vm_fault_t finish_fault(struct vm_fault *vmf) else page = vmf->page; + /* + * Just backoff if any subpage of a THP is corrupted otherwise + * the corrupted page may mapped by PMD silently to escape the + * check. This kind of THP just can be PTE mapped. Access to + * the corrupted subpage should trigger SIGBUS as expected. + */ + if (unlikely(PageHasHWPoisoned(page))) + return ret; + /* * check even for read faults because we might have lost our CoWed * page diff --git a/mm/page_alloc.c b/mm/page_alloc.c index e8e0f1cec8b0..8fc88df45293 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -1232,8 +1232,10 @@ static __always_inline bool free_pages_prepare(struct page *page, VM_BUG_ON_PAGE(compound && compound_order(page) != order, page); - if (compound) + if (compound) { ClearPageDoubleMap(page); + ClearPageHasHWPoisoned(page); + } for (i = 1; i < (1 << order); i++) { if (compound) bad += free_tail_pages_check(page, page + i);