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=-19.1 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_GIT 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 54E02C43460 for ; Mon, 17 May 2021 15:33:45 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 3563E61166 for ; Mon, 17 May 2021 15:33:45 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S245205AbhEQPeV (ORCPT ); Mon, 17 May 2021 11:34:21 -0400 Received: from mail.kernel.org ([198.145.29.99]:51696 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S244143AbhEQPTS (ORCPT ); Mon, 17 May 2021 11:19:18 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 6414F61C76; Mon, 17 May 2021 14:33:50 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1621262030; bh=wANwn/r44ErjICI6BND58o0NYrEVFW5L9D4tm+uV7ME=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=0VCkmSa+CgD+OhuspA06xlSZokBM1oz4eI5dOqyOifsTxGbXjWDbmS7ZlliLY2CKe +JHcgtwRquZUrfOpzrwuBpUahATElCsWOKNdqpLew18c/MTI3KI6vs7XKPhtzRvRpd EUhZXgHGCeqIJzH5X4fQQKrLk+4FebcGikGLnKNU= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Pavel Tatashin , Jason Gunthorpe , Dan Williams , David Hildenbrand , David Rientjes , Ingo Molnar , Ira Weiny , James Morris , Jason Gunthorpe , John Hubbard , Joonsoo Kim , Matthew Wilcox , Mel Gorman , Michal Hocko , Michal Hocko , Mike Kravetz , Oscar Salvador , Peter Zijlstra , Sasha Levin , "Steven Rostedt (VMware)" , Tyler Hicks , Vlastimil Babka , Andrew Morton , Linus Torvalds Subject: [PATCH 5.11 206/329] mm/gup: return an error on migration failure Date: Mon, 17 May 2021 16:01:57 +0200 Message-Id: <20210517140309.089039294@linuxfoundation.org> X-Mailer: git-send-email 2.31.1 In-Reply-To: <20210517140302.043055203@linuxfoundation.org> References: <20210517140302.043055203@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Pavel Tatashin [ Upstream commit f0f4463837da17a89d965dcbe4e411629dbcf308 ] When migration failure occurs, we still pin pages, which means that we may pin CMA movable pages which should never be the case. Instead return an error without pinning pages when migration failure happens. No need to retry migrating, because migrate_pages() already retries 10 times. Link: https://lkml.kernel.org/r/20210215161349.246722-4-pasha.tatashin@soleen.com Signed-off-by: Pavel Tatashin Reviewed-by: Jason Gunthorpe Cc: Dan Williams Cc: David Hildenbrand Cc: David Rientjes Cc: Ingo Molnar Cc: Ira Weiny Cc: James Morris Cc: Jason Gunthorpe Cc: John Hubbard Cc: Joonsoo Kim Cc: Matthew Wilcox Cc: Mel Gorman Cc: Michal Hocko Cc: Michal Hocko Cc: Mike Kravetz Cc: Oscar Salvador Cc: Peter Zijlstra Cc: Sasha Levin Cc: Steven Rostedt (VMware) Cc: Tyler Hicks Cc: Vlastimil Babka Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Sasha Levin --- mm/gup.c | 17 +++++++---------- 1 file changed, 7 insertions(+), 10 deletions(-) diff --git a/mm/gup.c b/mm/gup.c index 84d392886d85..2d7a567b4056 100644 --- a/mm/gup.c +++ b/mm/gup.c @@ -1550,7 +1550,6 @@ static long check_and_migrate_cma_pages(struct mm_struct *mm, { unsigned long i; bool drain_allow = true; - bool migrate_allow = true; LIST_HEAD(cma_page_list); long ret = nr_pages; struct page *prev_head, *head; @@ -1601,17 +1600,15 @@ check_again: for (i = 0; i < nr_pages; i++) put_page(pages[i]); - if (migrate_pages(&cma_page_list, alloc_migration_target, NULL, - (unsigned long)&mtc, MIGRATE_SYNC, MR_CONTIG_RANGE)) { - /* - * some of the pages failed migration. Do get_user_pages - * without migration. - */ - migrate_allow = false; - + ret = migrate_pages(&cma_page_list, alloc_migration_target, + NULL, (unsigned long)&mtc, MIGRATE_SYNC, + MR_CONTIG_RANGE); + if (ret) { if (!list_empty(&cma_page_list)) putback_movable_pages(&cma_page_list); + return ret > 0 ? -ENOMEM : ret; } + /* * We did migrate all the pages, Try to get the page references * again migrating any new CMA pages which we failed to isolate @@ -1621,7 +1618,7 @@ check_again: pages, vmas, NULL, gup_flags); - if ((ret > 0) && migrate_allow) { + if (ret > 0) { nr_pages = ret; drain_allow = true; goto check_again; -- 2.30.2