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=-5.7 required=3.0 tests=FROM_LOCAL_HEX, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING, SPF_PASS 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 EA96FC10F13 for ; Sun, 14 Apr 2019 11:28:11 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id B763A20848 for ; Sun, 14 Apr 2019 11:28:11 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726803AbfDNL2F (ORCPT ); Sun, 14 Apr 2019 07:28:05 -0400 Received: from mail-io1-f69.google.com ([209.85.166.69]:57050 "EHLO mail-io1-f69.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726147AbfDNL2F (ORCPT ); Sun, 14 Apr 2019 07:28:05 -0400 Received: by mail-io1-f69.google.com with SMTP id s184so11715863iod.23 for ; Sun, 14 Apr 2019 04:28:04 -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=769YfXKssij9gZTfBkexrYXVFn8YvgOBBOpY/r95PmU=; b=jhaFrP8tQJM5zOPwcnY9w0+DUDAtaXf2cpaToh3K6reFb++aZ+P/kQ5aifVpIT1mM9 8CbQHf9nwHDI7+TjEb4rEIeI2AEHo+u33J1Y1+w8PRB3EuTIDCYr1Rx8NTiZIz9b9Zxr KMlLKxfKPOOCgZ0xpTMg5FTA3eU4HZrXWfFmMPxwximlnpOscGhglCroHWywSirm5ic9 jrePNPMatq3GUgaQwqZT3u6SG2VNs3VY32s1Zo7WjuitX9ZsDrMcDR8JU2hWjaLVkli2 kM/tObWvzdw9+cSonP/NU9ej1jOUTCh9FgeVkH59bpm2tVAJjDOUiAezW6gqKBu2HM+F KgVg== X-Gm-Message-State: APjAAAVMCygpqTkdYGSe7Inrg0qBOm3u5EjY59Y/6cdFy53DPcvnIuzT 83BbaJo8YFlTrDWyutgBoI9GIMHS5avIGMPzMsz8SrTm/7CU X-Google-Smtp-Source: APXvYqx6TKnL5341UFyVF3+LROvh+Iamt2pmZa1OOOoon4ncgK7Rmh2h3eCnRwF94S9uVn4qwMP+q0WEVESkqPF/grd0VXDLyR5I MIME-Version: 1.0 X-Received: by 2002:a6b:ea14:: with SMTP id m20mr2982294ioc.33.1555241284579; Sun, 14 Apr 2019 04:28:04 -0700 (PDT) Date: Sun, 14 Apr 2019 04:28:04 -0700 X-Google-Appengine-App-Id: s~syzkaller X-Google-Appengine-App-Id-Alias: syzkaller Message-ID: <0000000000004ebb8a05867bd4ee@google.com> Subject: INFO: task hung in __ia32_sys_io_uring_enter From: syzbot To: axboe@kernel.dk, linux-block@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, syzkaller-bugs@googlegroups.com, viro@zeniv.linux.org.uk Content-Type: text/plain; charset="UTF-8"; format=flowed; delsp=yes Sender: linux-fsdevel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org Hello, syzbot found the following crash on: HEAD commit: 8ee15f32 Merge tag 'dma-mapping-5.1-1' of git://git.infrad.. git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=13b2e69f200000 kernel config: https://syzkaller.appspot.com/x/.config?x=4fb64439e07a1ec0 dashboard link: https://syzkaller.appspot.com/bug?extid=96642d282922abc6ef90 compiler: gcc (GCC) 9.0.0 20181231 (experimental) userspace arch: i386 Unfortunately, I don't have any reproducer for this crash yet. IMPORTANT: if you fix the bug, please add the following tag to the commit: Reported-by: syzbot+96642d282922abc6ef90@syzkaller.appspotmail.com INFO: task syz-executor.2:6936 blocked for more than 143 seconds. Not tainted 5.1.0-rc4+ #64 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.2 D27432 6936 7877 0x20020004 Call Trace: context_switch kernel/sched/core.c:2877 [inline] __schedule+0x817/0x1cc0 kernel/sched/core.c:3518 schedule+0x92/0x180 kernel/sched/core.c:3562 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3620 __mutex_lock_common kernel/locking/mutex.c:1002 [inline] __mutex_lock+0x726/0x1310 kernel/locking/mutex.c:1072 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1087 __do_sys_io_uring_enter fs/io_uring.c:2674 [inline] __se_sys_io_uring_enter fs/io_uring.c:2633 [inline] __ia32_sys_io_uring_enter+0x67f/0xac0 fs/io_uring.c:2633 do_syscall_32_irqs_on arch/x86/entry/common.c:326 [inline] do_fast_syscall_32+0x281/0xc98 arch/x86/entry/common.c:397 entry_SYSENTER_compat+0x70/0x7f arch/x86/entry/entry_64_compat.S:139 RIP: 0023:0xf7fdf869 Code: Bad RIP value. RSP: 002b:00000000f5ddb0cc EFLAGS: 00000296 ORIG_RAX: 00000000000001aa RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000000009 RDX: 0000000000000006 RSI: 0000000000000002 RDI: 0000000020000180 RBP: 0000000000000008 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 INFO: task syz-executor.2:6941 blocked for more than 143 seconds. Not tainted 5.1.0-rc4+ #64 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.2 D30304 6941 7877 0x20020004 Call Trace: context_switch kernel/sched/core.c:2877 [inline] __schedule+0x817/0x1cc0 kernel/sched/core.c:3518 schedule+0x92/0x180 kernel/sched/core.c:3562 schedule_timeout+0x8ca/0xfd0 kernel/time/timer.c:1779 do_wait_for_common kernel/sched/completion.c:83 [inline] __wait_for_common kernel/sched/completion.c:104 [inline] wait_for_common kernel/sched/completion.c:115 [inline] wait_for_completion+0x29c/0x440 kernel/sched/completion.c:136 __io_uring_register+0xb6/0x1fd0 fs/io_uring.c:2925 __do_sys_io_uring_register fs/io_uring.c:2975 [inline] __se_sys_io_uring_register fs/io_uring.c:2957 [inline] __ia32_sys_io_uring_register+0x193/0x1f0 fs/io_uring.c:2957 do_syscall_32_irqs_on arch/x86/entry/common.c:326 [inline] do_fast_syscall_32+0x281/0xc98 arch/x86/entry/common.c:397 entry_SYSENTER_compat+0x70/0x7f arch/x86/entry/entry_64_compat.S:139 RIP: 0023:0xf7fdf869 Code: Bad RIP value. RSP: 002b:00000000f5dba0cc EFLAGS: 00000296 ORIG_RAX: 00000000000001ab RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000000001 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 Showing all locks held in the system: 1 lock held by khungtaskd/1042: #0: 000000000fd6a12d (rcu_read_lock){....}, at: debug_show_all_locks+0x5f/0x27e kernel/locking/lockdep.c:5061 1 lock held by rsyslogd/7748: #0: 00000000b7bd7c78 (&f->f_pos_lock){+.+.}, at: __fdget_pos+0xee/0x110 fs/file.c:801 2 locks held by getty/7837: #0: 000000002675dd1e (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 000000008bb68d6f (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156 2 locks held by getty/7838: #0: 000000000272332d (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 000000006c00cca5 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156 2 locks held by getty/7839: #0: 0000000083b27adb (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 00000000778dee56 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156 2 locks held by getty/7840: #0: 00000000919ed15e (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 00000000dc8f8c82 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156 2 locks held by getty/7841: #0: 00000000a69742ff (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 00000000cc818dd5 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156 2 locks held by getty/7842: #0: 0000000031f786e7 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 00000000c793de16 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156 2 locks held by getty/7843: #0: 00000000c09fbaf2 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 000000000915b78b (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156 2 locks held by kworker/u4:4/3512: #0: 00000000c5d7093f (&rq->lock){-.-.}, at: idle_balance kernel/sched/fair.c:10053 [inline] #0: 00000000c5d7093f (&rq->lock){-.-.}, at: pick_next_task_fair+0x1214/0x19a0 kernel/sched/fair.c:7062 #1: 000000000fd6a12d (rcu_read_lock){....}, at: __update_idle_core+0x45/0x3f0 kernel/sched/fair.c:6059 1 lock held by syz-executor.2/6936: #0: 0000000020d6f30f (&ctx->uring_lock){+.+.}, at: __do_sys_io_uring_enter fs/io_uring.c:2674 [inline] #0: 0000000020d6f30f (&ctx->uring_lock){+.+.}, at: __se_sys_io_uring_enter fs/io_uring.c:2633 [inline] #0: 0000000020d6f30f (&ctx->uring_lock){+.+.}, at: __ia32_sys_io_uring_enter+0x67f/0xac0 fs/io_uring.c:2633 1 lock held by syz-executor.2/6941: #0: 0000000020d6f30f (&ctx->uring_lock){+.+.}, at: __do_sys_io_uring_register fs/io_uring.c:2974 [inline] #0: 0000000020d6f30f (&ctx->uring_lock){+.+.}, at: __se_sys_io_uring_register fs/io_uring.c:2957 [inline] #0: 0000000020d6f30f (&ctx->uring_lock){+.+.}, at: __ia32_sys_io_uring_register+0x182/0x1f0 fs/io_uring.c:2957 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 1042 Comm: khungtaskd Not tainted 5.1.0-rc4+ #64 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x172/0x1f0 lib/dump_stack.c:113 nmi_cpu_backtrace.cold+0x63/0xa4 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x1be/0x236 lib/nmi_backtrace.c:62 arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:38 trigger_all_cpu_backtrace include/linux/nmi.h:146 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:204 [inline] watchdog+0x9b7/0xec0 kernel/hung_task.c:288 kthread+0x357/0x430 kernel/kthread.c:253 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:352 Sending NMI from CPU 0 to CPUs 1: --- This bug 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 bug report. See: https://goo.gl/tpsmEJ#status for how to communicate with syzbot.