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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 4DB26C433EF for ; Wed, 11 May 2022 15:21:36 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1343513AbiEKPVe (ORCPT ); Wed, 11 May 2022 11:21:34 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:60378 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1343529AbiEKPVA (ORCPT ); Wed, 11 May 2022 11:21:00 -0400 Received: from out2.migadu.com (out2.migadu.com [188.165.223.204]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id B16A451596 for ; Wed, 11 May 2022 08:20:54 -0700 (PDT) X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1652282452; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding; bh=Rzhs0+3mpYIaNiRF6hUvhEnCu4nhoi9lUCf4jFRkxqs=; b=CXVZc00cgUB5mP2z2C//gZiNEYZesk2gn1jH84J3hYPq2tlrNWvtaMvso1E+I0m23bUOWY AfgXDXxJmW6QU1bMFd7bA/mK71q2PLGQN0Vlc2v1h9o9MueEj9asDZh9wW6L9DimhTthIx 3iqkVbXnEJnGB5QBv+ADtB7bzxoZiIM= From: Naoya Horiguchi To: linux-mm@kvack.org Cc: Andrew Morton , zhenwei pi , Miaohe Lin , Mike Kravetz , Naoya Horiguchi , linux-kernel@vger.kernel.org Subject: [PATCH v1] mm,hwpoison: set PG_hwpoison for busy hugetlb pages Date: Thu, 12 May 2022 00:19:55 +0900 Message-Id: <20220511151955.3951352-1-naoya.horiguchi@linux.dev> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Migadu-Flow: FLOW_OUT X-Migadu-Auth-User: linux.dev Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Naoya Horiguchi If memory_failure() fails to grab page refcount on a hugetlb page because it's busy, it returns without setting PG_hwpoison on it. This not only loses a chance of error containment, but breaks the rule that action_result() should be called only when memory_failure() do any of handling work (even if that's just setting PG_hwpoison). This inconsistency could harm code maintainability. So set PG_hwpoison and call hugetlb_set_page_hwpoison() for such a case. Fixes: 405ce051236c ("mm/hwpoison: fix race between hugetlb free/demotion and memory_failure_hugetlb()") Signed-off-by: Naoya Horiguchi --- include/linux/mm.h | 1 + mm/memory-failure.c | 8 ++++---- 2 files changed, 5 insertions(+), 4 deletions(-) diff --git a/include/linux/mm.h b/include/linux/mm.h index d446e834a3e5..04de0c3e4f9f 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -3187,6 +3187,7 @@ enum mf_flags { MF_MUST_KILL = 1 << 2, MF_SOFT_OFFLINE = 1 << 3, MF_UNPOISON = 1 << 4, + MF_NO_RETRY = 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/memory-failure.c b/mm/memory-failure.c index 6a28d020a4da..e3269b991016 100644 --- a/mm/memory-failure.c +++ b/mm/memory-failure.c @@ -1526,7 +1526,8 @@ int __get_huge_page_for_hwpoison(unsigned long pfn, int flags) count_increased = true; } else { ret = -EBUSY; - goto out; + if (!(flags & MF_NO_RETRY)) + goto out; } if (TestSetPageHWPoison(head)) { @@ -1556,7 +1557,6 @@ static int try_memory_failure_hugetlb(unsigned long pfn, int flags, int *hugetlb struct page *p = pfn_to_page(pfn); struct page *head; unsigned long page_flags; - bool retry = true; *hugetlb = 1; retry: @@ -1572,8 +1572,8 @@ static int try_memory_failure_hugetlb(unsigned long pfn, int flags, int *hugetlb } return res; } else if (res == -EBUSY) { - if (retry) { - retry = false; + if (!(flags & MF_NO_RETRY)) { + flags |= MF_NO_RETRY; goto retry; } action_result(pfn, MF_MSG_UNKNOWN, MF_IGNORED); -- 2.25.1