From nobody Sun Dec 14 21:24:56 2025 Received: from szxga05-in.huawei.com (szxga05-in.huawei.com [45.249.212.191]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id C9160149E00 for ; Mon, 17 Feb 2025 01:52:56 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=45.249.212.191 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1739757179; cv=none; b=NKKLcEf0wTOf5Lxmuup6l2VBVgLAbsKLrVB7uB1hmO6OZ4vnCu6Il9u7J9VKnOQPo0o8DdzQObutXSakNgOgIAXRVgAECx3WTKQMry5kWbyzRzch+/4LnFBs5Tf+7l23VRav5sNjxhnyAnSJqDKdu0Cgg7mbNK8bOfCjV96PimI= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1739757179; c=relaxed/simple; bh=q9jbMPlarU7oJg9mEj5aj3sjg4ret6lxK4pjJehmmsE=; h=From:To:CC:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=ISEQGH6qYpjUQTjDg4nsRz51pYBi8QJmrQnPiw4sE/MMg2iQElwKmQBNQLoKy0Y/KrFx/j7gWsDNPLBHwmFC65xHinaMPjteYiVOH0iKnNlyJXYXtKVhAO1l/A+59Vn0Ju9kONZmpCPgS+HAMnNsCGRVXUYtSYMpVUgwZ++YEHw= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=huawei.com; spf=pass smtp.mailfrom=huawei.com; arc=none smtp.client-ip=45.249.212.191 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=huawei.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=huawei.com Received: from mail.maildlp.com (unknown [172.19.88.214]) by szxga05-in.huawei.com (SkyGuard) with ESMTP id 4Yx5Gv64C1z11P4m; Mon, 17 Feb 2025 09:51:19 +0800 (CST) Received: from kwepemg100017.china.huawei.com (unknown [7.202.181.58]) by mail.maildlp.com (Postfix) with ESMTPS id E67D51A0171; Mon, 17 Feb 2025 09:52:47 +0800 (CST) Received: from huawei.com (10.175.124.71) by kwepemg100017.china.huawei.com (7.202.181.58) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.1544.11; Mon, 17 Feb 2025 09:52:47 +0800 From: Wupeng Ma To: , , , , , CC: , , Subject: [PATCH v3 1/3] mm: memory-failure: update ttu flag inside unmap_poisoned_folio Date: Mon, 17 Feb 2025 09:43:27 +0800 Message-ID: <20250217014329.3610326-2-mawupeng1@huawei.com> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20250217014329.3610326-1-mawupeng1@huawei.com> References: <20250217014329.3610326-1-mawupeng1@huawei.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-ClientProxiedBy: dggems705-chm.china.huawei.com (10.3.19.182) To kwepemg100017.china.huawei.com (7.202.181.58) Content-Type: text/plain; charset="utf-8" From: Ma Wupeng Commit 6da6b1d4a7df ("mm/hwpoison: convert TTU_IGNORE_HWPOISON to TTU_HWPOISON") introduce TTU_HWPOISON to replace TTU_IGNORE_HWPOISON in order to stop send SIGBUS signal when accessing an error page after a memory error on a clean folio. However during page migration, anon folio must be set with TTU_HWPOISON during unmap_*(). For pagecache we need some policy just like the one in hwpoison_user_mappings to set this flag. So move this policy from hwpoison_user_mappings to unmap_poisoned_folio to handle this warning properly. Warning will be produced during unamp poison folio with the following log: ------------[ cut here ]------------ WARNING: CPU: 1 PID: 365 at mm/rmap.c:1847 try_to_unmap_one+0x8fc/0xd3c Modules linked in: CPU: 1 UID: 0 PID: 365 Comm: bash Tainted: G W 6.13.0-rc1= -00018-gacdb4bbda7ab #42 Tainted: [W]=3DWARN Hardware name: QEMU QEMU Virtual Machine, BIOS 0.0.0 02/06/2015 pstate: 20400005 (nzCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=3D--) pc : try_to_unmap_one+0x8fc/0xd3c lr : try_to_unmap_one+0x3dc/0xd3c Call trace: try_to_unmap_one+0x8fc/0xd3c (P) try_to_unmap_one+0x3dc/0xd3c (L) rmap_walk_anon+0xdc/0x1f8 rmap_walk+0x3c/0x58 try_to_unmap+0x88/0x90 unmap_poisoned_folio+0x30/0xa8 do_migrate_range+0x4a0/0x568 offline_pages+0x5a4/0x670 memory_block_action+0x17c/0x374 memory_subsys_offline+0x3c/0x78 device_offline+0xa4/0xd0 state_store+0x8c/0xf0 dev_attr_store+0x18/0x2c sysfs_kf_write+0x44/0x54 kernfs_fop_write_iter+0x118/0x1a8 vfs_write+0x3a8/0x4bc ksys_write+0x6c/0xf8 __arm64_sys_write+0x1c/0x28 invoke_syscall+0x44/0x100 el0_svc_common.constprop.0+0x40/0xe0 do_el0_svc+0x1c/0x28 el0_svc+0x30/0xd0 el0t_64_sync_handler+0xc8/0xcc el0t_64_sync+0x198/0x19c ---[ end trace 0000000000000000 ]--- Fixes: 6da6b1d4a7df ("mm/hwpoison: convert TTU_IGNORE_HWPOISON to TTU_HWPOI= SON") Suggested-by: David Hildenbrand Signed-off-by: Ma Wupeng Acked-by: David Hildenbrand Acked-by: Miaohe Lin --- mm/internal.h | 5 ++-- mm/memory-failure.c | 61 +++++++++++++++++++++++---------------------- mm/memory_hotplug.c | 3 ++- 3 files changed, 36 insertions(+), 33 deletions(-) diff --git a/mm/internal.h b/mm/internal.h index 9826f7dce607..c9186ca8d7c2 100644 --- a/mm/internal.h +++ b/mm/internal.h @@ -1102,7 +1102,7 @@ static inline int find_next_best_node(int node, nodem= ask_t *used_node_mask) * mm/memory-failure.c */ #ifdef CONFIG_MEMORY_FAILURE -void unmap_poisoned_folio(struct folio *folio, enum ttu_flags ttu); +int unmap_poisoned_folio(struct folio *folio, unsigned long pfn, bool must= _kill); void shake_folio(struct folio *folio); extern int hwpoison_filter(struct page *p); =20 @@ -1125,8 +1125,9 @@ unsigned long page_mapped_in_vma(const struct page *p= age, struct vm_area_struct *vma); =20 #else -static inline void unmap_poisoned_folio(struct folio *folio, enum ttu_flag= s ttu) +static inline int unmap_poisoned_folio(struct folio *folio, unsigned long = pfn, bool must_kill) { + return -EBUSY; } #endif =20 diff --git a/mm/memory-failure.c b/mm/memory-failure.c index a7b8ccd29b6f..b5212b6e330a 100644 --- a/mm/memory-failure.c +++ b/mm/memory-failure.c @@ -1556,8 +1556,34 @@ static int get_hwpoison_page(struct page *p, unsigne= d long flags) return ret; } =20 -void unmap_poisoned_folio(struct folio *folio, enum ttu_flags ttu) +int unmap_poisoned_folio(struct folio *folio, unsigned long pfn, bool must= _kill) { + enum ttu_flags ttu =3D TTU_IGNORE_MLOCK | TTU_SYNC | TTU_HWPOISON; + struct address_space *mapping; + + if (folio_test_swapcache(folio)) { + pr_err("%#lx: keeping poisoned page in swap cache\n", pfn); + ttu &=3D ~TTU_HWPOISON; + } + + /* + * Propagate the dirty bit from PTEs to struct page first, because we + * need this to decide if we should kill or just drop the page. + * XXX: the dirty test could be racy: set_page_dirty() may not always + * be called inside page lock (it's recommended but not enforced). + */ + mapping =3D folio_mapping(folio); + if (!must_kill && !folio_test_dirty(folio) && mapping && + mapping_can_writeback(mapping)) { + if (folio_mkclean(folio)) { + folio_set_dirty(folio); + } else { + ttu &=3D ~TTU_HWPOISON; + pr_info("%#lx: corrupted page was clean: dropped without side effects\n= ", + pfn); + } + } + if (folio_test_hugetlb(folio) && !folio_test_anon(folio)) { struct address_space *mapping; =20 @@ -1572,7 +1598,7 @@ void unmap_poisoned_folio(struct folio *folio, enum t= tu_flags ttu) if (!mapping) { pr_info("%#lx: could not lock mapping for mapped hugetlb folio\n", folio_pfn(folio)); - return; + return -EBUSY; } =20 try_to_unmap(folio, ttu|TTU_RMAP_LOCKED); @@ -1580,6 +1606,8 @@ void unmap_poisoned_folio(struct folio *folio, enum t= tu_flags ttu) } else { try_to_unmap(folio, ttu); } + + return folio_mapped(folio) ? -EBUSY : 0; } =20 /* @@ -1589,8 +1617,6 @@ void unmap_poisoned_folio(struct folio *folio, enum t= tu_flags ttu) static bool hwpoison_user_mappings(struct folio *folio, struct page *p, unsigned long pfn, int flags) { - enum ttu_flags ttu =3D TTU_IGNORE_MLOCK | TTU_SYNC | TTU_HWPOISON; - struct address_space *mapping; LIST_HEAD(tokill); bool unmap_success; int forcekill; @@ -1613,29 +1639,6 @@ static bool hwpoison_user_mappings(struct folio *fol= io, struct page *p, if (!folio_mapped(folio)) return true; =20 - if (folio_test_swapcache(folio)) { - pr_err("%#lx: keeping poisoned page in swap cache\n", pfn); - ttu &=3D ~TTU_HWPOISON; - } - - /* - * Propagate the dirty bit from PTEs to struct page first, because we - * need this to decide if we should kill or just drop the page. - * XXX: the dirty test could be racy: set_page_dirty() may not always - * be called inside page lock (it's recommended but not enforced). - */ - mapping =3D folio_mapping(folio); - if (!(flags & MF_MUST_KILL) && !folio_test_dirty(folio) && mapping && - mapping_can_writeback(mapping)) { - if (folio_mkclean(folio)) { - folio_set_dirty(folio); - } else { - ttu &=3D ~TTU_HWPOISON; - pr_info("%#lx: corrupted page was clean: dropped without side effects\n= ", - pfn); - } - } - /* * First collect all the processes that have the page * mapped in dirty form. This has to be done before try_to_unmap, @@ -1643,9 +1646,7 @@ static bool hwpoison_user_mappings(struct folio *foli= o, struct page *p, */ collect_procs(folio, p, &tokill, flags & MF_ACTION_REQUIRED); =20 - unmap_poisoned_folio(folio, ttu); - - unmap_success =3D !folio_mapped(folio); + unmap_success =3D !unmap_poisoned_folio(folio, pfn, flags & MF_MUST_KILL); if (!unmap_success) pr_err("%#lx: failed to unmap page (folio mapcount=3D%d)\n", pfn, folio_mapcount(folio)); diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c index c43b4e7fb298..3de661e57e92 100644 --- a/mm/memory_hotplug.c +++ b/mm/memory_hotplug.c @@ -1806,7 +1806,8 @@ static void do_migrate_range(unsigned long start_pfn,= unsigned long end_pfn) if (WARN_ON(folio_test_lru(folio))) folio_isolate_lru(folio); if (folio_mapped(folio)) - unmap_poisoned_folio(folio, TTU_IGNORE_MLOCK); + unmap_poisoned_folio(folio, pfn, false); + continue; } =20 --=20 2.43.0