From patchwork Thu Sep 2 21:58:40 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Andrew Morton X-Patchwork-Id: 506276 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 5640DC433FE for ; Thu, 2 Sep 2021 21:58:47 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 43DD460E8B for ; Thu, 2 Sep 2021 21:58:47 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1347966AbhIBV7o (ORCPT ); Thu, 2 Sep 2021 17:59:44 -0400 Received: from mail.kernel.org ([198.145.29.99]:55382 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1347960AbhIBV7k (ORCPT ); Thu, 2 Sep 2021 17:59:40 -0400 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 Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org 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)