From patchwork Fri Apr 2 09:32:49 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Miaohe Lin X-Patchwork-Id: 12180591 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=-16.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=ham 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 CFC37C43460 for ; Fri, 2 Apr 2021 09:33:53 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 6B29860FED for ; Fri, 2 Apr 2021 09:33:53 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 6B29860FED Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=huawei.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id E85B46B0075; Fri, 2 Apr 2021 05:33:50 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id E60A26B0078; Fri, 2 Apr 2021 05:33:50 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id C152E6B007D; Fri, 2 Apr 2021 05:33:50 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0218.hostedemail.com [216.40.44.218]) by kanga.kvack.org (Postfix) with ESMTP id A4D396B0075 for ; Fri, 2 Apr 2021 05:33:50 -0400 (EDT) Received: from smtpin16.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay03.hostedemail.com (Postfix) with ESMTP id 4C0C1824559C for ; Fri, 2 Apr 2021 09:33:50 +0000 (UTC) X-FDA: 77986915020.16.BC80991 Received: from szxga07-in.huawei.com (szxga07-in.huawei.com [45.249.212.35]) by imf10.hostedemail.com (Postfix) with ESMTP id 4AA8340002D3 for ; Fri, 2 Apr 2021 09:33:48 +0000 (UTC) Received: from DGGEMS408-HUB.china.huawei.com (unknown [172.30.72.60]) by szxga07-in.huawei.com (SkyGuard) with ESMTP id 4FBZZ263Nsz9vvQ; Fri, 2 Apr 2021 17:31:38 +0800 (CST) Received: from huawei.com (10.175.104.175) by DGGEMS408-HUB.china.huawei.com (10.3.19.208) with Microsoft SMTP Server id 14.3.498.0; Fri, 2 Apr 2021 17:33:36 +0800 From: Miaohe Lin To: , CC: , , , , Subject: [PATCH 4/4] mm/hugeltb: handle the error case in hugetlb_fix_reserve_counts() Date: Fri, 2 Apr 2021 05:32:49 -0400 Message-ID: <20210402093249.25137-5-linmiaohe@huawei.com> X-Mailer: git-send-email 2.19.1 In-Reply-To: <20210402093249.25137-1-linmiaohe@huawei.com> References: <20210402093249.25137-1-linmiaohe@huawei.com> MIME-Version: 1.0 X-Originating-IP: [10.175.104.175] X-CFilter-Loop: Reflected X-Rspamd-Server: rspam01 X-Rspamd-Queue-Id: 4AA8340002D3 X-Stat-Signature: jck36kgsxt6ssx5geyhuzddh3cydtwhj Received-SPF: none (huawei.com>: No applicable sender policy available) receiver=imf10; identity=mailfrom; envelope-from=""; helo=szxga07-in.huawei.com; client-ip=45.249.212.35 X-HE-DKIM-Result: none/none X-HE-Tag: 1617356028-59433 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: A rare out of memory error would prevent removal of the reserve map region for a page. hugetlb_fix_reserve_counts() handles this rare case to avoid dangling with incorrect counts. Unfortunately, hugepage_subpool_get_pages and hugetlb_acct_memory could possibly fail too. We should correctly handle these cases. Fixes: b5cec28d36f5 ("hugetlbfs: truncate_hugepages() takes a range of pages") Signed-off-by: Miaohe Lin --- mm/hugetlb.c | 11 +++++++++-- 1 file changed, 9 insertions(+), 2 deletions(-) diff --git a/mm/hugetlb.c b/mm/hugetlb.c index bdff8d23803f..ca5464ed04b7 100644 --- a/mm/hugetlb.c +++ b/mm/hugetlb.c @@ -745,13 +745,20 @@ void hugetlb_fix_reserve_counts(struct inode *inode) { struct hugepage_subpool *spool = subpool_inode(inode); long rsv_adjust; + bool reserved = false; rsv_adjust = hugepage_subpool_get_pages(spool, 1); - if (rsv_adjust) { + if (rsv_adjust > 0) { struct hstate *h = hstate_inode(inode); - hugetlb_acct_memory(h, 1); + if (!hugetlb_acct_memory(h, 1)) + reserved = true; + } else if (!rsv_adjust) { + reserved = true; } + + if (!reserved) + pr_warn("hugetlb: fix reserve count failed\n"); } /*