From nobody Mon Apr 27 09:13:38 2026 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 5368BCCA47A for ; Wed, 15 Jun 2022 02:05:07 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239433AbiFOCFF (ORCPT ); Tue, 14 Jun 2022 22:05:05 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:34090 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S239432AbiFOCFD (ORCPT ); Tue, 14 Jun 2022 22:05:03 -0400 Received: from mail-pj1-x102f.google.com (mail-pj1-x102f.google.com [IPv6:2607:f8b0:4864:20::102f]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id D659A4C79C for ; Tue, 14 Jun 2022 19:05:02 -0700 (PDT) Received: by mail-pj1-x102f.google.com with SMTP id cx11so9981649pjb.1 for ; Tue, 14 Jun 2022 19:05:02 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bytedance-com.20210112.gappssmtp.com; s=20210112; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=Ep2sWjEOrgSF336dlpmSeKloAzp4+PSakvgoXseW1lo=; b=mmB1Pq0SmF+MQtE0Vmg4IYkIXjXDa5r5drYmX1DTPSbrymbOsu0LIWOu2GqOXX7/sD LybOzWWS50ius7/f8fWYcZNMegR0a97Syjaf4z6AmerU2CMB4jHVIVKDjEKNHbnW3OhB C8VBSQQ5ToabLpBJc0R6L5IXP21eTHa2xkjsetNiJIKqjNEDwqNayALGmP16ee+neT2Y BbKWa7utZpaih6wnv8S2Ujh9qqvvRY0Jyn+EAgME6LKVdK7gYyW9Zja72jnTPXUfRpYc Kdg8fCJCTU8UPWjtG/JWsE/GSlTJ5nIOcyTCRKC9ePw9AYMLIS33XA6tQeHnwzLiUQi5 0pOg== 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=Ep2sWjEOrgSF336dlpmSeKloAzp4+PSakvgoXseW1lo=; b=I4EqDQnNnTjvMVfof2mpHHqiRB/WoOfHngfHVKSDYqCecbGRRYJQjJTX+p7G1xY+g7 SzrgmMESIlwF+csap0nsm6mFuapKU7QDItSUDu5xNBc+FnFZyku8VY3AfP6DwNdoEC23 i14err/olribCmF79PJaDFaBFSvNR8nTu4Oz2mfEnwTnxGIVi8xVGPE7TP/zKRNsmZOZ bPWYCuCqb7/NKvn+K/tVIqaL54FiZpXiz9d25iL6cIvzltZn5KcqqP5PKThl1pYH2adX z19Xwi/FfqZleNlqfYMotRRCiJjFHhHTct/IULuOqIdCI5D6qEXNdEUBSApPKHeRQjbv SXaQ== X-Gm-Message-State: AOAM532UaBH0McBru9q8WTN0ii82khdtm7JLgfkPSdfs5mhcCS59F/as rPVUoPCgzLV1MkOAQmvPrDOv7g== X-Google-Smtp-Source: ABdhPJyhtjVtLESv2UIwOi7gfxkUawtd7TckD4a15TywnCw9LkIojwicsZN5yN/SgL3AHrpzIDpAkg== X-Received: by 2002:a17:902:ea03:b0:166:ab55:d7ee with SMTP id s3-20020a170902ea0300b00166ab55d7eemr6918665plg.103.1655258702254; Tue, 14 Jun 2022 19:05:02 -0700 (PDT) Received: from always-x1.bytedance.net ([61.120.150.70]) by smtp.gmail.com with ESMTPSA id f17-20020aa79691000000b00518d06efbc8sm8538290pfk.98.2022.06.14.19.04.58 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 14 Jun 2022 19:05:01 -0700 (PDT) From: zhenwei pi To: pizhenwei@bytedance.com, naoya.horiguchi@nec.com, akpm@linux-foundation.org Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, david@redhat.com, linmiaohe@huawei.com, gregkh@linuxfoundation.org Subject: [PATCH v5 1/1] mm/memory-failure: disable unpoison once hw error happens Date: Wed, 15 Jun 2022 10:00:05 +0800 Message-Id: <20220615020005.246295-2-pizhenwei@bytedance.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20220615020005.246295-1-pizhenwei@bytedance.com> References: <20220615020005.246295-1-pizhenwei@bytedance.com> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" Currently unpoison_memory(unsigned long pfn) is designed for soft poison(hwpoison-inject) only. Since 17fae1294ad9d, the KPTE gets cleared on a x86 platform once hardware memory corrupts. Unpoisoning a hardware corrupted page puts page back buddy only, the kernel has a chance to access the page with *NOT PRESENT* KPTE. This leads BUG during accessing on the corrupted KPTE. Suggested by David&Naoya, disable unpoison mechanism when a real HW error happens to avoid BUG like this: Unpoison: Software-unpoisoned page 0x61234 BUG: unable to handle page fault for address: ffff888061234000 #PF: supervisor write access in kernel mode #PF: error_code(0x0002) - not-present page PGD 2c01067 P4D 2c01067 PUD 107267063 PMD 10382b063 PTE 800fffff9edcb062 Oops: 0002 [#1] PREEMPT SMP NOPTI CPU: 4 PID: 26551 Comm: stress Kdump: loaded Tainted: G M OE 5= .18.0.bm.1-amd64 #7 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996) ... RIP: 0010:clear_page_erms+0x7/0x10 Code: ... RSP: 0000:ffffc90001107bc8 EFLAGS: 00010246 RAX: 0000000000000000 RBX: 0000000000000901 RCX: 0000000000001000 RDX: ffffea0001848d00 RSI: ffffea0001848d40 RDI: ffff888061234000 RBP: ffffea0001848d00 R08: 0000000000000901 R09: 0000000000001276 R10: 0000000000000003 R11: 0000000000000000 R12: 0000000000000001 R13: 0000000000000000 R14: 0000000000140dca R15: 0000000000000001 FS: 00007fd8b2333740(0000) GS:ffff88813fd00000(0000) knlGS:00000000000000= 00 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffff888061234000 CR3: 00000001023d2005 CR4: 0000000000770ee0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 PKRU: 55555554 Call Trace: prep_new_page+0x151/0x170 get_page_from_freelist+0xca0/0xe20 ? sysvec_apic_timer_interrupt+0xab/0xc0 ? asm_sysvec_apic_timer_interrupt+0x1b/0x20 __alloc_pages+0x17e/0x340 __folio_alloc+0x17/0x40 vma_alloc_folio+0x84/0x280 __handle_mm_fault+0x8d4/0xeb0 handle_mm_fault+0xd5/0x2a0 do_user_addr_fault+0x1d0/0x680 ? kvm_read_and_reset_apf_flags+0x3b/0x50 exc_page_fault+0x78/0x170 asm_exc_page_fault+0x27/0x30 Fixes: 847ce401df392 ("HWPOISON: Add unpoisoning support") Fixes: 17fae1294ad9d ("x86/{mce,mm}: Unmap the entire page if the whole pag= e is affected and poisoned") Cc: Naoya Horiguchi Cc: David Hildenbrand Signed-off-by: zhenwei pi Acked-by: David Hildenbrand --- Documentation/vm/hwpoison.rst | 3 ++- drivers/base/memory.c | 2 +- include/linux/mm.h | 1 + mm/hwpoison-inject.c | 2 +- mm/madvise.c | 2 +- mm/memory-failure.c | 12 ++++++++++++ 6 files changed, 18 insertions(+), 4 deletions(-) diff --git a/Documentation/vm/hwpoison.rst b/Documentation/vm/hwpoison.rst index c742de1769d1..b9d5253c1305 100644 --- a/Documentation/vm/hwpoison.rst +++ b/Documentation/vm/hwpoison.rst @@ -120,7 +120,8 @@ Testing unpoison-pfn Software-unpoison page at PFN echoed into this file. This way a page can be reused again. This only works for Linux - injected failures, not for real memory failures. + injected failures, not for real memory failures. Once any hardware + memory failure happens, this feature is disabled. =20 Note these injection interfaces are not stable and might change between kernel versions diff --git a/drivers/base/memory.c b/drivers/base/memory.c index 084d67fd55cc..bc60c9cd3230 100644 --- a/drivers/base/memory.c +++ b/drivers/base/memory.c @@ -558,7 +558,7 @@ static ssize_t hard_offline_page_store(struct device *d= ev, if (kstrtoull(buf, 0, &pfn) < 0) return -EINVAL; pfn >>=3D PAGE_SHIFT; - ret =3D memory_failure(pfn, 0); + ret =3D memory_failure(pfn, MF_SW_SIMULATED); if (ret =3D=3D -EOPNOTSUPP) ret =3D 0; return ret ? ret : count; diff --git a/include/linux/mm.h b/include/linux/mm.h index bc8f326be0ce..4346e51484ba 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -3232,6 +3232,7 @@ enum mf_flags { MF_MUST_KILL =3D 1 << 2, MF_SOFT_OFFLINE =3D 1 << 3, MF_UNPOISON =3D 1 << 4, + MF_SW_SIMULATED =3D 1 << 5, }; extern int memory_failure(unsigned long pfn, int flags); extern void memory_failure_queue(unsigned long pfn, int flags); diff --git a/mm/hwpoison-inject.c b/mm/hwpoison-inject.c index 5c0cddd81505..65e242b5a432 100644 --- a/mm/hwpoison-inject.c +++ b/mm/hwpoison-inject.c @@ -48,7 +48,7 @@ static int hwpoison_inject(void *data, u64 val) =20 inject: pr_info("Injecting memory failure at pfn %#lx\n", pfn); - err =3D memory_failure(pfn, 0); + err =3D memory_failure(pfn, MF_SW_SIMULATED); return (err =3D=3D -EOPNOTSUPP) ? 0 : err; } =20 diff --git a/mm/madvise.c b/mm/madvise.c index d7b4f2602949..0316bbc6441b 100644 --- a/mm/madvise.c +++ b/mm/madvise.c @@ -1112,7 +1112,7 @@ static int madvise_inject_error(int behavior, } else { pr_info("Injecting memory failure for pfn %#lx at process virtual addre= ss %#lx\n", pfn, start); - ret =3D memory_failure(pfn, MF_COUNT_INCREASED); + ret =3D memory_failure(pfn, MF_COUNT_INCREASED | MF_SW_SIMULATED); if (ret =3D=3D -EOPNOTSUPP) ret =3D 0; } diff --git a/mm/memory-failure.c b/mm/memory-failure.c index b85661cbdc4a..385b5e99bfc1 100644 --- a/mm/memory-failure.c +++ b/mm/memory-failure.c @@ -69,6 +69,8 @@ int sysctl_memory_failure_recovery __read_mostly =3D 1; =20 atomic_long_t num_poisoned_pages __read_mostly =3D ATOMIC_LONG_INIT(0); =20 +static bool hw_memory_failure; + static bool __page_handle_poison(struct page *page) { int ret; @@ -1768,6 +1770,9 @@ int memory_failure(unsigned long pfn, int flags) =20 mutex_lock(&mf_mutex); =20 + if (!(flags & MF_SW_SIMULATED)) + hw_memory_failure =3D true; + p =3D pfn_to_online_page(pfn); if (!p) { res =3D arch_memory_failure(pfn, flags); @@ -2103,6 +2108,13 @@ int unpoison_memory(unsigned long pfn) =20 mutex_lock(&mf_mutex); =20 + if (hw_memory_failure) { + unpoison_pr_info("Unpoison: Disabled after HW memory failure %#lx\n", + pfn, &unpoison_rs); + ret =3D -EOPNOTSUPP; + goto unlock_mutex; + } + if (!PageHWPoison(p)) { unpoison_pr_info("Unpoison: Page was already unpoisoned %#lx\n", pfn, &unpoison_rs); --=20 2.20.1