From nobody Tue Apr 28 01:11:08 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 6817CC43334 for ; Wed, 8 Jun 2022 09:21:19 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235029AbiFHJVP (ORCPT ); Wed, 8 Jun 2022 05:21:15 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:41252 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235341AbiFHJTT (ORCPT ); Wed, 8 Jun 2022 05:19:19 -0400 Received: from mail-pg1-x52b.google.com (mail-pg1-x52b.google.com [IPv6:2607:f8b0:4864:20::52b]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 1E63155493 for ; Wed, 8 Jun 2022 01:42:08 -0700 (PDT) Received: by mail-pg1-x52b.google.com with SMTP id c18so9947353pgh.11 for ; Wed, 08 Jun 2022 01:42:08 -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=sb98wOh0APW10cVV6EJOE4BAB6aJnap4z+dh4wykpTE=; b=PD0WVIoUek3vJ8vo3YueL2euoEvexCCdJGTthjFnw3auR4gD9xc1+AbopFWA1zwqy0 82gksE0mRUEyOv2RcXw0a1KqiUTCDkFnZ5Q76oD7UBPjehdyJZ4f3Ns3kiM8QoAcn4qg eorXMvVxsq/K8+DAJA0pfuvt4Bl6HcSHnmgsD+V1g53sSYTzCkdlQ98xzT1WKturK2AC 179hX0duKXG1F25gLFaxbA3HfT8OwarJuX5XrZV4T5HTYzn1v1M2BASrx3TNPFKtSSGW aWu4D5rmdloe/3tSKVy6BcB6fiZQeD7hvl8Mn3YVsMXezz+tnd1Skp0n0dLKtP/0Wi7l BF4A== 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=sb98wOh0APW10cVV6EJOE4BAB6aJnap4z+dh4wykpTE=; b=z7v/sMhhmI0+WZS65WubX39oEYpMU+wiGrMGBueVdEqVMLcAZ12EzGccQlo49MWOAT ETBx/RfFokz6Mq3X6us8g8ZoM2Kb5MYmb+jxcWvxU2mgEPAAfJbXo5GGm7qmdnJ1bbvO MKAd+URMTmBqstt13CGfRfSuasMZ6KcN0C4q6H43b7tAi3EYZA7mNqvSfa0LemDVvw+1 Kts5mf9LrEVS+2Umwii36iUtZ1GUvARbzExnEz5ceyXi2OqrUGKYU0oKu6eCOtz3FMAp l+vuhIVSCS38fI5jxHs0xmPren8KHir2OSn+quvcBBtVwqDq4A4SSKpJbxiHaH8+8t6g zN2Q== X-Gm-Message-State: AOAM530RjuPp4d+CMkCr/hqeocd/zWOuYCBgih9gzdMRCOwi/nbQsX1c zdawhQ4o//zhO79N6CTNXdjZ+w== X-Google-Smtp-Source: ABdhPJyoJ4K+iVeEl6Rbs51QAba7tVuMh9rDessrajKigQLxtfCxPF3vsrhTpRahDeitRdzx4JUGTQ== X-Received: by 2002:a63:5d21:0:b0:3fa:387b:7b44 with SMTP id r33-20020a635d21000000b003fa387b7b44mr29190274pgb.48.1654677727578; Wed, 08 Jun 2022 01:42:07 -0700 (PDT) Received: from always-T480.www.tendawifi.com ([139.177.225.254]) by smtp.gmail.com with ESMTPSA id u30-20020a63b55e000000b003fc136f9a7dsm2180975pgo.38.2022.06.08.01.42.04 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 08 Jun 2022 01:42:06 -0700 (PDT) From: zhenwei pi To: akpm@linux-foundation.org, naoya.horiguchi@nec.com Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, zhenwei pi Subject: [PATCH v2 1/1] mm/memory-failure: don't allow to unpoison hw corrupted page Date: Wed, 8 Jun 2022 16:43:56 +0800 Message-Id: <20220608084356.40894-2-pizhenwei@bytedance.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20220608084356.40894-1-pizhenwei@bytedance.com> References: <20220608084356.40894-1-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. Do not allow to unpoison hardware corrupted page in unpoison_memory() 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 Signed-off-by: zhenwei pi --- mm/memory-failure.c | 9 +++++++++ 1 file changed, 9 insertions(+) diff --git a/mm/memory-failure.c b/mm/memory-failure.c index b85661cbdc4a..da99a2b7ef35 100644 --- a/mm/memory-failure.c +++ b/mm/memory-failure.c @@ -2090,6 +2090,7 @@ int unpoison_memory(unsigned long pfn) { struct page *page; struct page *p; + pte_t *kpte; int ret =3D -EBUSY; int freeit =3D 0; static DEFINE_RATELIMIT_STATE(unpoison_rs, DEFAULT_RATELIMIT_INTERVAL, @@ -2103,6 +2104,14 @@ int unpoison_memory(unsigned long pfn) =20 mutex_lock(&mf_mutex); =20 + kpte =3D virt_to_kpte((unsigned long)page_to_virt(p)); + if (kpte && !pte_present(*kpte)) { + unpoison_pr_info("Unpoison: Page was hardware poisoned %#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