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 50E34C433EF for ; Thu, 30 Jun 2022 02:28:51 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231555AbiF3C2t (ORCPT ); Wed, 29 Jun 2022 22:28:49 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:48056 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231518AbiF3C2g (ORCPT ); Wed, 29 Jun 2022 22:28:36 -0400 Received: from out2.migadu.com (out2.migadu.com [188.165.223.204]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 162DAB846 for ; Wed, 29 Jun 2022 19:28:33 -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=1656556112; 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: in-reply-to:in-reply-to:references:references; bh=SI3BXzvQ1paTor1nht5oQndWpNg1sLLCA8PWdy7uGZs=; b=Wg7Kx1F6zatg0dpsAhIlsBbPFC5GUv6pxbEgRdbnnSrtjXCG9nO/CH7GNsy4i3F/BPBX4u b5qw2lr4r8OE13qoFbKwAUOtYxFC8UEoxSSkEM2KUVhglk6nJKKWZ/TThRaGmjIrgNka38 KWoOu0M1FgLTr9Ac3EaYVxx79iGXU3s= From: Naoya Horiguchi To: linux-mm@kvack.org Cc: Andrew Morton , David Hildenbrand , Mike Kravetz , Miaohe Lin , Liu Shixin , Yang Shi , Oscar Salvador , Muchun Song , Naoya Horiguchi , linux-kernel@vger.kernel.org Subject: [PATCH v3 6/9] mm, hwpoison: set PG_hwpoison for busy hugetlb pages Date: Thu, 30 Jun 2022 11:27:52 +0900 Message-Id: <20220630022755.3362349-7-naoya.horiguchi@linux.dev> In-Reply-To: <20220630022755.3362349-1-naoya.horiguchi@linux.dev> References: <20220630022755.3362349-1-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 Reviewed-by: Miaohe Lin --- 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 4346e51484ba..044dc5a2e361 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -3233,6 +3233,7 @@ enum mf_flags { MF_SOFT_OFFLINE = 1 << 3, MF_UNPOISON = 1 << 4, MF_SW_SIMULATED = 1 << 5, + MF_NO_RETRY = 1 << 6, }; 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 dc90bfadb1dd..81e591cf8b4a 100644 --- a/mm/memory-failure.c +++ b/mm/memory-failure.c @@ -1617,7 +1617,8 @@ 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 (hugetlb_set_page_hwpoison(head, page)) { @@ -1644,7 +1645,6 @@ 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: @@ -1660,8 +1660,8 @@ 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