From patchwork Tue Aug 31 20:24:39 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Andrew Morton X-Patchwork-Id: 505704 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-15.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id A79D9C4320A for ; Tue, 31 Aug 2021 20:24:41 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 8400A61026 for ; Tue, 31 Aug 2021 20:24:41 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S241086AbhHaUZg (ORCPT ); Tue, 31 Aug 2021 16:25:36 -0400 Received: from mail.kernel.org ([198.145.29.99]:50624 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S241028AbhHaUZf (ORCPT ); Tue, 31 Aug 2021 16:25:35 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id DC36060F23; Tue, 31 Aug 2021 20:24:39 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux-foundation.org; s=korg; t=1630441480; bh=yDCqkILFvm9fAJPJkR8tyuea8O+63omCDcjVE0x7Z5c=; h=Date:From:To:Subject:From; b=SO3Ht7nSmS+HyO5rk0m5KejCmAcp/EVqK8HDa6RpKiykudFFRCeAGeOkEQ1tKqeJM 5+FZL7mZbOlNH9I2z5nJ842QnZC/Ltl13BfSKDowlXLhcyA55FF8eSRMHfpcefQ6lG dwrksr5jC8lOsNU6ziujAv/VtcEyjYhHETMyPaec= Date: Tue, 31 Aug 2021 13:24:39 -0700 From: akpm@linux-foundation.org To: abaci@linux.alibaba.com, mm-commits@vger.kernel.org, naoya.horiguchi@nec.com, stable@vger.kernel.org, yun.wang@linux.alibaba.com Subject: + mm-fix-panic-caused-by-__page_handle_poison.patch added to -mm tree Message-ID: <20210831202439.jkeWd26U_%akpm@linux-foundation.org> User-Agent: s-nail v14.8.16 Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org The patch titled Subject: mm: fix panic caused by __page_handle_poison() has been added to the -mm tree. Its filename is mm-fix-panic-caused-by-__page_handle_poison.patch This patch should soon appear at https://ozlabs.org/~akpm/mmots/broken-out/mm-fix-panic-caused-by-__page_handle_poison.patch and later at https://ozlabs.org/~akpm/mmotm/broken-out/mm-fix-panic-caused-by-__page_handle_poison.patch Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/process/submit-checklist.rst when testing your code *** The -mm tree is included into linux-next and is updated there every 3-4 working days ------------------------------------------------------ From: Michael Wang Subject: mm: fix panic caused by __page_handle_poison() In commit 510d25c92ec4 ("mm/hwpoison: disable pcp for page_handle_poison()"), __page_handle_poison() was introduced, and if we mark: RET_A = dissolve_free_huge_page(); RET_B = take_page_off_buddy(); then __page_handle_poison was supposed to return TRUE When RET_A == 0 && RET_B == TRUE But since it failed to take care the case when RET_A is -EBUSY or -ENOMEM, and just return the ret as a bool which actually become TRUE, it break the original logic. The following result is a huge page in freelist but was referenced as poisoned, and lead into the final panic: kernel BUG at mm/internal.h:95! invalid opcode: 0000 [#1] SMP PTI skip... RIP: 0010:set_page_refcounted mm/internal.h:95 [inline] RIP: 0010:remove_hugetlb_page+0x23c/0x240 mm/hugetlb.c:1371 skip... Call Trace: remove_pool_huge_page+0xe4/0x110 mm/hugetlb.c:1892 return_unused_surplus_pages+0x8d/0x150 mm/hugetlb.c:2272 hugetlb_acct_memory.part.91+0x524/0x690 mm/hugetlb.c:4017 This patch replaces 'bool' with 'int' to handle RET_A correctly. Link: https://lkml.kernel.org/r/61782ac6-1e8a-4f6f-35e6-e94fce3b37f5@linux.alibaba.com Fixes: 510d25c92ec4 ("mm/hwpoison: disable pcp for page_handle_poison()") Signed-off-by: Michael Wang Acked-by: Naoya Horiguchi Reported-by: Abaci Cc: [5.14+] Signed-off-by: Andrew Morton --- mm/memory-failure.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) --- a/mm/memory-failure.c~mm-fix-panic-caused-by-__page_handle_poison +++ a/mm/memory-failure.c @@ -68,7 +68,7 @@ atomic_long_t num_poisoned_pages __read_ static bool __page_handle_poison(struct page *page) { - bool ret; + int ret; zone_pcp_disable(page_zone(page)); ret = dissolve_free_huge_page(page); @@ -76,7 +76,7 @@ static bool __page_handle_poison(struct ret = take_page_off_buddy(page); zone_pcp_enable(page_zone(page)); - return ret; + return ret > 0; } static bool page_handle_poison(struct page *page, bool hugepage_or_freepage, bool release)