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 kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id 7CE6FC43334 for ; Fri, 15 Jul 2022 09:25:05 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 07D1F9401DE; Fri, 15 Jul 2022 05:25:05 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 02E3A9401A5; Fri, 15 Jul 2022 05:25:04 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id E5EC99401DE; Fri, 15 Jul 2022 05:25:04 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0015.hostedemail.com [216.40.44.15]) by kanga.kvack.org (Postfix) with ESMTP id D410E9401A5 for ; Fri, 15 Jul 2022 05:25:04 -0400 (EDT) Received: from smtpin10.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay12.hostedemail.com (Postfix) with ESMTP id A96EE1204DD for ; Fri, 15 Jul 2022 09:25:04 +0000 (UTC) X-FDA: 79688800128.10.AB05A2B Received: from szxga01-in.huawei.com (szxga01-in.huawei.com [45.249.212.187]) by imf16.hostedemail.com (Postfix) with ESMTP id 92FF4180075 for ; Fri, 15 Jul 2022 09:25:03 +0000 (UTC) Received: from kwepemi500016.china.huawei.com (unknown [172.30.72.56]) by szxga01-in.huawei.com (SkyGuard) with ESMTP id 4Lkm8t1mzJzjWyB; Fri, 15 Jul 2022 17:22:22 +0800 (CST) Received: from huawei.com (10.175.112.208) by kwepemi500016.china.huawei.com (7.221.188.220) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2375.24; Fri, 15 Jul 2022 17:24:59 +0800 From: Zhou Guanghui To: CC: , , Subject: [PATCH] mm/huge_memory: Return from zap_huge_pmd after WARN_ONCE. Date: Fri, 15 Jul 2022 09:22:38 +0000 Message-ID: <20220715092238.22663-1-zhouguanghui1@huawei.com> X-Mailer: git-send-email 2.17.1 MIME-Version: 1.0 Content-Type: text/plain X-Originating-IP: [10.175.112.208] X-ClientProxiedBy: dggems705-chm.china.huawei.com (10.3.19.182) To kwepemi500016.china.huawei.com (7.221.188.220) X-CFilter-Loop: Reflected ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1657877104; a=rsa-sha256; cv=none; b=6ZRgKdO5f08XLbg99lMgBLh/h89tdFeBw2/gp0kX/9zkMWvtTL/6Ijh/hLFa8VnIU99X5Q jyhbYZAVR5FxTJNZRr+7smslvM9c8eSD5FOFnBpnodUlppeDvkkQjfWJvfVP1bT4wppJN+ 74Mv8lXDYkpftkAeVCnGaNw2FUI99hA= ARC-Authentication-Results: i=1; imf16.hostedemail.com; dkim=none; dmarc=pass (policy=quarantine) header.from=huawei.com; spf=pass (imf16.hostedemail.com: domain of zhouguanghui1@huawei.com designates 45.249.212.187 as permitted sender) smtp.mailfrom=zhouguanghui1@huawei.com ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1657877104; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type:content-transfer-encoding:in-reply-to: references; bh=FzPQhJmHWFXGzFAm+88lDLSCWMfe1euz6GXYCRziBTA=; b=wwj2LhqvRAzdyULW9dbyB48BMvha7JDWwli+HFxQPRJRxF87xJiZX/9ilWZiExJStGR1LP 71QbJYyNa5x4HeRqpZs/dtvPxa9y4gnfql+6MPXY6VG4jf4Qh75VGXs1vTMg956UN0HC/+ 83heElW+I//xhTTF68yQfzNF1idM/W4= X-Stat-Signature: skg9rzcq6j53n5sw6mqs1t5nxxxop8wm X-Rspam-User: X-Rspamd-Queue-Id: 92FF4180075 Authentication-Results: imf16.hostedemail.com; dkim=none; dmarc=pass (policy=quarantine) header.from=huawei.com; spf=pass (imf16.hostedemail.com: domain of zhouguanghui1@huawei.com designates 45.249.212.187 as permitted sender) smtp.mailfrom=zhouguanghui1@huawei.com X-Rspamd-Server: rspam11 X-HE-Tag: 1657877103-35661 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: After WARN_ONCE is processed, the subsequent page judgment results in NULL pointer access. It is more reasonable to return from the function here. Signed-off-by: Zhou Guanghui --- mm/huge_memory.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/mm/huge_memory.c b/mm/huge_memory.c index 834f288b3769..7f5ccca6792a 100644 --- a/mm/huge_memory.c +++ b/mm/huge_memory.c @@ -1601,8 +1601,11 @@ int zap_huge_pmd(struct mmu_gather *tlb, struct vm_area_struct *vma, entry = pmd_to_swp_entry(orig_pmd); page = pfn_swap_entry_to_page(entry); flush_needed = 0; - } else + } else { + spin_unlock(ptl); WARN_ONCE(1, "Non present huge pmd without pmd migration enabled!"); + return 1; + } if (PageAnon(page)) { zap_deposited_table(tlb->mm, pmd); -- 2.17.1