From mboxrd@z Thu Jan 1 00:00:00 1970 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=ham 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 8DD08C433EF for ; Thu, 2 Sep 2021 21:58:43 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 440986056B for ; Thu, 2 Sep 2021 21:58:43 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org 440986056B Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=linux-foundation.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=kvack.org Received: by kanga.kvack.org (Postfix) id DF2B66B016F; Thu, 2 Sep 2021 17:58:42 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id D7DA56B0170; Thu, 2 Sep 2021 17:58:42 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id BCEA18D0001; Thu, 2 Sep 2021 17:58:42 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0053.hostedemail.com [216.40.44.53]) by kanga.kvack.org (Postfix) with ESMTP id A86C26B016F for ; Thu, 2 Sep 2021 17:58:42 -0400 (EDT) Received: from smtpin08.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay04.hostedemail.com (Postfix) with ESMTP id 751DF2BFA4 for ; Thu, 2 Sep 2021 21:58:42 +0000 (UTC) X-FDA: 78543998484.08.8DC3963 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by imf05.hostedemail.com (Postfix) with ESMTP id 3B98C5047447 for ; Thu, 2 Sep 2021 21:58:42 +0000 (UTC) Received: by mail.kernel.org (Postfix) with ESMTPSA id 4685D60F12; Thu, 2 Sep 2021 21:58:41 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux-foundation.org; s=korg; t=1630619921; bh=Hwr15fGwIvezpliPxy+tuM8+SSJ6UmqrSw1CVEf+YfE=; h=Date:From:To:Subject:In-Reply-To:From; b=ViBpMlZYxq8UBtRudo1dzt+W+HtG10PIdTMMuemHYpJImvkdEoN9Qy/GNdtsfol72 xWz+gswND+5KMkqds96FzF9kzEYfu4xLSKqu4PH/VfhwCmiZ0roB60c5Nae8o/w54i JJyMEblyab1V3LqjPa3V3q1zVX6TaOxWnral8mSk= Date: Thu, 02 Sep 2021 14:58:40 -0700 From: Andrew Morton To: abaci@linux.alibaba.com, akpm@linux-foundation.org, linux-mm@kvack.org, mm-commits@vger.kernel.org, naoya.horiguchi@nec.com, stable@vger.kernel.org, torvalds@linux-foundation.org, yun.wang@linux.alibaba.com Subject: [patch 165/212] mm: fix panic caused by __page_handle_poison() Message-ID: <20210902215840.lw0-MrokA%akpm@linux-foundation.org> In-Reply-To: <20210902144820.78957dff93d7bea620d55a89@linux-foundation.org> User-Agent: s-nail v14.8.16 Authentication-Results: imf05.hostedemail.com; dkim=pass header.d=linux-foundation.org header.s=korg header.b=ViBpMlZY; dmarc=none; spf=pass (imf05.hostedemail.com: domain of akpm@linux-foundation.org designates 198.145.29.99 as permitted sender) smtp.mailfrom=akpm@linux-foundation.org X-Rspamd-Server: rspam03 X-Rspamd-Queue-Id: 3B98C5047447 X-Stat-Signature: z19muoxki4h8m7tx13c8nubs4izzdsmi X-HE-Tag: 1630619922-388345 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: 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) _