From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Google-Smtp-Source: AB8JxZp3D2Y2txDg6EWQ4eLYa9prgcOFy+LNFhbtvTSS0LLj9fIwYw4qPppESox4EoNaYBF8WwTi ARC-Seal: i=1; a=rsa-sha256; t=1524837620; cv=none; d=google.com; s=arc-20160816; b=n7pThMQ6UodP2B/VRiVOOoRCxNs9JCkSZpHer6aRKZCJFu1Xcwu2xnZQlg6p54Rpzm Ls5oGQe1aWabLAcmchVkzSsRDf1bP/lk+ZD4vTU9mvNge4jvRpNOWYnDa7gXCml5B5LD eZz7W1S/ktfpSRCH1TjY6+5e+LgyfCiEmrQQalVRgPTI/x7vjLkTDxJ+7Smh80zNVsD4 O4oBJyXd5PeD+2k2dngpr/XM2G1Ca6jfiE3jozTH3ABzbtuOFL5bgAlsC9JNEtVCPELZ FRUmhuvVxjF2zBTF1zy4ky1IyBhjSUtxq+H7L1bCfbF84suw/DEC3wYBXCaret1L1ew5 dYDA== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=mime-version:user-agent:references:in-reply-to:message-id:date :subject:cc:to:from:dmarc-filter:arc-authentication-results; bh=/hBdTwQFFq92tpDTBR59Kh6LVMX5yCRpSOtI7ZWzqpg=; b=Heb0oa+FhHzPKrRPJ/koVGsiAxciOUicZMfw02BTrZ9zv6RVSoDFDGR6wTEAHbtemX zXihU3NQurJGdTt1iVYB5FVVn9GYSqv5lBJv8DjxhtlqAiFczyFpPYksIujxPtzZNB35 T2UmaEMdxHAdfmBnu5KnYjAcGbGiWVII1wYd/GK8qWbowqs9gCd5T/TP5jtMt3ltKlII U4hrWNWgi0lwXs+3ZMv3C4XFyLTPxo0NfQOqUgswniBUfk1Qi0BDdgpmnyzDehYSq3a3 oC2Q57urQMQ+SxxOSzdIicHwVmnwArTKHHYzDIeck9AP0Cj1AwCSvWrToGslvXkS2b8U P+ow== ARC-Authentication-Results: i=1; mx.google.com; spf=pass (google.com: best guess record for domain of srs0=4/0d=hq=linuxfoundation.org=gregkh@kernel.org designates 198.145.29.99 as permitted sender) smtp.mailfrom=SRS0=4/0d=HQ=linuxfoundation.org=gregkh@kernel.org Authentication-Results: mx.google.com; spf=pass (google.com: best guess record for domain of srs0=4/0d=hq=linuxfoundation.org=gregkh@kernel.org designates 198.145.29.99 as permitted sender) smtp.mailfrom=SRS0=4/0d=HQ=linuxfoundation.org=gregkh@kernel.org DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 8FFCE21894 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=linuxfoundation.org Authentication-Results: mail.kernel.org; spf=fail smtp.mailfrom=gregkh@linuxfoundation.org From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, wangguang , Theodore Tso , Nathan Chancellor , Harsh Shandilya Subject: [PATCH 3.18 04/24] ext4: bugfix for mmaped pages in mpage_release_unused_pages() Date: Fri, 27 Apr 2018 15:57:39 +0200 Message-Id: <20180427135631.764487030@linuxfoundation.org> X-Mailer: git-send-email 2.17.0 In-Reply-To: <20180427135631.584839868@linuxfoundation.org> References: <20180427135631.584839868@linuxfoundation.org> User-Agent: quilt/0.65 X-stable: review MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 X-getmail-retrieved-from-mailbox: INBOX X-GMAIL-LABELS: =?utf-8?b?IlxcU2VudCI=?= X-GMAIL-THRID: =?utf-8?q?1598908132982127189?= X-GMAIL-MSGID: =?utf-8?q?1598908132982127189?= X-Mailing-List: linux-kernel@vger.kernel.org List-ID: 3.18-stable review patch. If anyone has any objections, please let me know. ------------------ From: wangguang commit 4e800c0359d9a53e6bf0ab216954971b2515247f upstream. Pages clear buffers after ext4 delayed block allocation failed, However, it does not clean its pte_dirty flag. if the pages unmap ,in cording to the pte_dirty , unmap_page_range may try to call __set_page_dirty, which may lead to the bugon at mpage_prepare_extent_to_map:head = page_buffers(page);. This patch just call clear_page_dirty_for_io to clean pte_dirty at mpage_release_unused_pages for pages mmaped. Steps to reproduce the bug: （1） mmap a file in ext4 addr = (char *)mmap(NULL, 4096, PROT_READ|PROT_WRITE, MAP_SHARED, fd, 0); memset(addr, 'i', 4096); （2） return EIO at ext4_writepages->mpage_map_and_submit_extent->mpage_map_one_extent which causes this log message to be print: ext4_msg(sb, KERN_CRIT, "Delayed block allocation failed for " "inode %lu at logical offset %llu with" " max blocks %u with error %d", inode->i_ino, (unsigned long long)map->m_lblk, (unsigned)map->m_len, -err); (3）Unmap the addr cause warning at __set_page_dirty:WARN_ON_ONCE(warn && !PageUptodate(page)); (4) wait for a minute,then bugon happen. Cc: stable@vger.kernel.org Signed-off-by: wangguang Signed-off-by: Theodore Ts'o [nathanchance: Resolved conflict from lack of 09cbfeaf1a5a6] Signed-off-by: Nathan Chancellor Signed-off-by: Harsh Shandilya Signed-off-by: Greg Kroah-Hartman --- fs/ext4/inode.c | 2 ++ 1 file changed, 2 insertions(+) --- a/fs/ext4/inode.c +++ b/fs/ext4/inode.c @@ -1338,6 +1338,8 @@ static void mpage_release_unused_pages(s BUG_ON(!PageLocked(page)); BUG_ON(PageWriteback(page)); if (invalidate) { + if (page_mapped(page)) + clear_page_dirty_for_io(page); block_invalidatepage(page, 0, PAGE_CACHE_SIZE); ClearPageUptodate(page); }