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 22BCCC43334 for ; Thu, 14 Jul 2022 04:30:20 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236362AbiGNEaS (ORCPT ); Thu, 14 Jul 2022 00:30:18 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:33184 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S236799AbiGNE3K (ORCPT ); Thu, 14 Jul 2022 00:29:10 -0400 Received: from out2.migadu.com (out2.migadu.com [188.165.223.204]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 4D89B27B34 for ; Wed, 13 Jul 2022 21:24:54 -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=1657772692; 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=ngKLKDdl8tKKfu2TGB+i86Efy0xem0/rhnoFe8dfEL8=; b=i+JllwS2lmZjxpmph0m/xZ/95qQFQ9W39AEul2qTClWf+jTSUEePa4iApnYrfC/HeX40oQ XCG/rCkeP3uZ9W6iZ2OkXG7QRLomr+H56pCZUBD7y+6ztKea7tfQRbzgubVccZ4tRPH7BV hd+wZo1QT5MjFHR8uEtDGxMqCrANJbc= 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: [mm-unstable PATCH v7 5/8] mm, hwpoison: set PG_hwpoison for busy hugetlb pages Date: Thu, 14 Jul 2022 13:24:17 +0900 Message-Id: <20220714042420.1847125-6-naoya.horiguchi@linux.dev> In-Reply-To: <20220714042420.1847125-1-naoya.horiguchi@linux.dev> References: <20220714042420.1847125-1-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 4287bec50c28..7668831c919f 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -3188,6 +3188,7 @@ enum mf_flags { MF_SOFT_OFFLINE = 1 << 3, MF_UNPOISON = 1 << 4, MF_SW_SIMULATED = 1 << 5, + MF_NO_RETRY = 1 << 6, }; int mf_dax_kill_procs(struct address_space *mapping, pgoff_t index, unsigned long count, int mf_flags); diff --git a/mm/memory-failure.c b/mm/memory-failure.c index 8b9c0d228549..f15d521c3f1f 100644 --- a/mm/memory-failure.c +++ b/mm/memory-failure.c @@ -1802,7 +1802,8 @@ 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)) { @@ -1829,7 +1830,6 @@ 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: @@ -1845,8 +1845,8 @@ 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