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=-3.7 required=3.0 tests=BAYES_00,FROM_LOCAL_HEX, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED autolearn=no 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 4FBACC4338F for ; Mon, 2 Aug 2021 18:24:23 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 00F8060F4B for ; Mon, 2 Aug 2021 18:24:22 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org 00F8060F4B Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=syzkaller.appspotmail.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=kvack.org Received: by kanga.kvack.org (Postfix) id 231EE6B0033; Mon, 2 Aug 2021 14:24:22 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 1E2026B0036; Mon, 2 Aug 2021 14:24:22 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 0D22C8D0001; Mon, 2 Aug 2021 14:24:22 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0171.hostedemail.com [216.40.44.171]) by kanga.kvack.org (Postfix) with ESMTP id E4D326B0033 for ; Mon, 2 Aug 2021 14:24:21 -0400 (EDT) Received: from smtpin40.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay01.hostedemail.com (Postfix) with ESMTP id 8DFFA180868DA for ; Mon, 2 Aug 2021 18:24:21 +0000 (UTC) X-FDA: 78430965522.40.F32FE50 Received: from mail-io1-f72.google.com (mail-io1-f72.google.com [209.85.166.72]) by imf23.hostedemail.com (Postfix) with ESMTP id 545BB9001B27 for ; Mon, 2 Aug 2021 18:24:21 +0000 (UTC) Received: by mail-io1-f72.google.com with SMTP id z17-20020a0566022051b0290528db19d5b3so12279424iod.5 for ; Mon, 02 Aug 2021 11:24:21 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:date:message-id:subject:from:to; bh=dM7GDnU8nOXRyfAEVEOxqM6Fk7+QZ9HlaDE6aJORJM8=; b=P8T1V9cXxcXUM+nRAXo7U7vTCSGKx1aLClHRv7IFC9lQ+m9CKuKvswYuLP1hQK2Zoa ImCGMuHCliIWvzjRBVVk9Ep199q/hhpxxg2U3tYwbJgiWzC9AGBveJH0du42VhWC9HYY LTd4TFWx7ZnxNM8psCksTur51mjs4DKjHxtJ1E9cjy0m3gjjJ7JIwOXmtjzv0q7c9Sr5 OMa+KaiEBd+eng+AOYY4lRtD6RJMwtyuc71TeOdkIL3MqfGyOanbd/l6GD4EY2iMkyg4 VdXNSDOR4kyK3uov98AF1zsVwW5tVDv/mli7NMjEJaNghV0ZiwRFMD6T/QkB5TXhcLfR 6pZQ== X-Gm-Message-State: AOAM533IEL//gkMVvWgnr6RJifGdyDA5zZQDHcxz9qkatAdAyVYYZ7j7 obYhnYfQjivxvgfNTL1P0PrKaTGT+aGkQRHceu/ccbywxK8x X-Google-Smtp-Source: ABdhPJz1rMlfxuBaM/JYjM7RMfvSGbCI52oJyZB78UU6nCzLNiJ7lpapILiOFpWY0dgNG82A9SlcqPmCYdZ9CY6z9so9AFF8B1H7 MIME-Version: 1.0 X-Received: by 2002:a92:190f:: with SMTP id 15mr838800ilz.45.1627928660791; Mon, 02 Aug 2021 11:24:20 -0700 (PDT) Date: Mon, 02 Aug 2021 11:24:20 -0700 X-Google-Appengine-App-Id: s~syzkaller X-Google-Appengine-App-Id-Alias: syzkaller Message-ID: <0000000000008bd88e05c897ad5f@google.com> Subject: [syzbot] divide error in wb_update_dirty_ratelimit From: syzbot To: akpm@linux-foundation.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, syzkaller-bugs@googlegroups.com Content-Type: text/plain; charset="UTF-8" X-Rspamd-Server: rspam06 X-Rspamd-Queue-Id: 545BB9001B27 Authentication-Results: imf23.hostedemail.com; dkim=none; spf=pass (imf23.hostedemail.com: domain of 3VDgIYQkbAPMntufVggZmVkkdY.bjjbgZpnZmXjioZio.Xjh@M3KW2WVRGUFZ5GODRSRYTGD7.apphosting.bounces.google.com designates 209.85.166.72 as permitted sender) smtp.mailfrom=3VDgIYQkbAPMntufVggZmVkkdY.bjjbgZpnZmXjioZio.Xjh@M3KW2WVRGUFZ5GODRSRYTGD7.apphosting.bounces.google.com; dmarc=fail reason="SPF not aligned (relaxed), No valid DKIM" header.from=appspotmail.com (policy=none) X-Stat-Signature: cwss6pmpbmuccjosisf9xbr6rr3b5mwb X-HE-Tag: 1627928661-348728 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: Hello, syzbot found the following issue on: HEAD commit: 8d4b477da1a8 Add linux-next specific files for 20210730 git tree: linux-next console output: https://syzkaller.appspot.com/x/log.txt?x=128ede56300000 kernel config: https://syzkaller.appspot.com/x/.config?x=4adf4987f875c210 dashboard link: https://syzkaller.appspot.com/bug?extid=6a04d6ba849df9d81239 compiler: gcc (Debian 10.2.1-6) 10.2.1 20210110, GNU ld (GNU Binutils for Debian) 2.35.1 Unfortunately, I don't have any reproducer for this issue yet. IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+6a04d6ba849df9d81239@syzkaller.appspotmail.com divide error: 0000 [#1] PREEMPT SMP KASAN CPU: 0 PID: 10430 Comm: syz-executor.3 Not tainted 5.14.0-rc3-next-20210730-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:wb_update_dirty_ratelimit+0x18d/0x7d0 mm/page-writeback.c:1197 Code: 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 80 3c 02 00 0f 85 af 05 00 00 4c 2b b5 30 02 00 00 49 8d 7f 58 31 d2 49 6b c6 64 <48> f7 f3 48 89 fa 48 89 04 24 48 b8 00 00 00 00 00 fc ff df 48 c1 RSP: 0018:ffffc9000551f750 EFLAGS: 00010206 RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffffc9000fdb1000 RDX: 0000000000000000 RSI: 0000000000006377 RDI: ffffc9000551f9a0 RBP: ffff888089632060 R08: 0000000000000000 R09: ffffffff9023d363 R10: fffffbfff2047a6c R11: 0000000000000000 R12: 0000000000006400 R13: 000000000003c2b1 R14: 0000000000000000 R15: ffffc9000551f948 FS: 00007fdc4e708700(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00000000206000bf CR3: 0000000073f41000 CR4: 00000000001506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __wb_update_bandwidth+0x3d7/0x5a0 mm/page-writeback.c:1350 balance_dirty_pages+0x12ab/0x29d0 mm/page-writeback.c:1719 balance_dirty_pages_ratelimited+0xda2/0x1820 mm/page-writeback.c:1920 generic_perform_write+0x320/0x510 mm/filemap.c:3789 __generic_file_write_iter+0x24e/0x610 mm/filemap.c:3882 generic_file_write_iter+0xd7/0x220 mm/filemap.c:3914 fuse_cache_write_iter fs/fuse/file.c:1298 [inline] fuse_file_write_iter+0x56c/0xcd0 fs/fuse/file.c:1601 call_write_iter include/linux/fs.h:2152 [inline] new_sync_write+0x426/0x650 fs/read_write.c:518 vfs_write+0x75a/0xa40 fs/read_write.c:605 ksys_write+0x12d/0x250 fs/read_write.c:658 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x4665e9 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 bc ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fdc4e708188 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 000000000056bf80 RCX: 00000000004665e9 RDX: 00000000fffffdef RSI: 00000000200000c0 RDI: 0000000000000006 RBP: 00000000004bfcc4 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056bf80 R13: 00007fff2d6f27cf R14: 00007fdc4e708300 R15: 0000000000022000 Modules linked in: ---[ end trace 01891e5696647ce8 ]--- RIP: 0010:wb_update_dirty_ratelimit+0x18d/0x7d0 mm/page-writeback.c:1197 Code: 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 80 3c 02 00 0f 85 af 05 00 00 4c 2b b5 30 02 00 00 49 8d 7f 58 31 d2 49 6b c6 64 <48> f7 f3 48 89 fa 48 89 04 24 48 b8 00 00 00 00 00 fc ff df 48 c1 RSP: 0018:ffffc9000551f750 EFLAGS: 00010206 RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffffc9000fdb1000 RDX: 0000000000000000 RSI: 0000000000006377 RDI: ffffc9000551f9a0 RBP: ffff888089632060 R08: 0000000000000000 R09: ffffffff9023d363 R10: fffffbfff2047a6c R11: 0000000000000000 R12: 0000000000006400 R13: 000000000003c2b1 R14: 0000000000000000 R15: ffffc9000551f948 FS: 00007fdc4e708700(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00000000206000bf CR3: 0000000073f41000 CR4: 00000000001506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 --- This report is generated by a bot. It may contain errors. See https://goo.gl/tpsmEJ for more information about syzbot. syzbot engineers can be reached at syzkaller@googlegroups.com. syzbot will keep track of this issue. See: https://goo.gl/tpsmEJ#status for how to communicate with syzbot.