syzbot


INFO: task hung in blk_freeze_queue

Status: fixed on 2018/07/09 18:05
Subsystems: block
[Documentation on labels]
Reported-by: syzbot+2ab52b8d94df5e2eaa01@syzkaller.appspotmail.com
Fix commit: d2ac838e4cd7 loop: add recursion validation to LOOP_CHANGE_FD
First crash: 2301d, last: 2150d
Discussions (2)
Title Replies (including bot) Last reply
[PATCH] loop: add recursion validation to LOOP_CHANGE_FD 17 (17) 2018/06/05 15:07
Re: INFO: task hung in blk_freeze_queue 2 (2) 2018/05/05 04:26
Similar bugs (4)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: task hung in blk_freeze_queue (4) block 2 393d 396d 0/26 auto-obsoleted due to no activity on 2023/07/28 15:48
upstream INFO: task hung in blk_freeze_queue (3) arm C 8 555d 634d 22/26 fixed on 2023/02/24 13:50
upstream INFO: task hung in blk_freeze_queue (2) block 1 2052d 2052d 0/26 auto-closed as invalid on 2019/04/12 00:55
linux-6.1 INFO: task hung in blk_freeze_queue origin:upstream C 1 8d06h 353d 0/3 upstream: reported C repro on 2023/06/08 14:42

Sample crash report:
random: sshd: uninitialized urandom read (32 bytes read)
random: sshd: uninitialized urandom read (32 bytes read)
random: sshd: uninitialized urandom read (32 bytes read)
random: sshd: uninitialized urandom read (32 bytes read)
random: sshd: uninitialized urandom read (32 bytes read)
INFO: task syz-executor413:4623 blocked for more than 120 seconds.
      Not tainted 4.17.0-rc6+ #66
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor413 D23216  4623   4621 0x00000000
Call Trace:
 context_switch kernel/sched/core.c:2859 [inline]
 __schedule+0x801/0x1e30 kernel/sched/core.c:3501
 schedule+0xef/0x430 kernel/sched/core.c:3545
 blk_mq_freeze_queue_wait+0x1ce/0x460 block/blk-mq.c:152
 blk_freeze_queue+0x4a/0x80 block/blk-mq.c:181
 blk_mq_freeze_queue+0x15/0x20 block/blk-mq.c:190
 loop_change_fd drivers/block/loop.c:689 [inline]
 lo_ioctl+0xa9a/0x2130 drivers/block/loop.c:1401
 __blkdev_driver_ioctl block/ioctl.c:303 [inline]
 blkdev_ioctl+0x9b6/0x2020 block/ioctl.c:601
 block_ioctl+0xee/0x130 fs/block_dev.c:1877
 vfs_ioctl fs/ioctl.c:46 [inline]
 file_ioctl fs/ioctl.c:500 [inline]
 do_vfs_ioctl+0x1cf/0x16a0 fs/ioctl.c:684
 ksys_ioctl+0xa9/0xd0 fs/ioctl.c:701
 __do_sys_ioctl fs/ioctl.c:708 [inline]
 __se_sys_ioctl fs/ioctl.c:706 [inline]
 __x64_sys_ioctl+0x73/0xb0 fs/ioctl.c:706
 do_syscall_64+0x1b1/0x800 arch/x86/entry/common.c:287
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x443dc9
RSP: 002b:00007ffef2d3a7a8 EFLAGS: 00000286 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 6f6f6c2f7665642f RCX: 0000000000443dc9
RDX: 0000000000000007 RSI: 0000000000004c06 RDI: 0000000000000007
RBP: 00000000006ce018 R08: 00000000004002e0 R09: 00000000004002e0
R10: 00000000004002e0 R11: 0000000000000286 R12: 0000000000401a70
R13: 0000000000401b00 R14: 0000000000000000 R15: 0000000000000000

Showing all locks held in the system:
2 locks held by khungtaskd/891:
 #0:         (ptrval) (rcu_read_lock){....}, at: check_hung_uninterruptible_tasks kernel/hung_task.c:175 [inline]
 #0:         (ptrval) (rcu_read_lock){....}, at: watchdog+0x1ff/0xf60 kernel/hung_task.c:249
 #1:         (ptrval) (tasklist_lock){.+.+}, at: debug_show_all_locks+0xde/0x34a kernel/locking/lockdep.c:4470
1 lock held by rsyslogd/4506:
 #0:         (ptrval) (&f->f_pos_lock){+.+.}, at: __fdget_pos+0x1a9/0x1e0 fs/file.c:766
2 locks held by getty/4597:
 #0:         (ptrval) (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365
 #1:         (ptrval) (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x321/0x1cc0 drivers/tty/n_tty.c:2131
2 locks held by getty/4598:
 #0:         (ptrval) (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365
 #1:         (ptrval) (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x321/0x1cc0 drivers/tty/n_tty.c:2131
2 locks held by getty/4599:
 #0:         (ptrval) (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365
 #1:         (ptrval) (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x321/0x1cc0 drivers/tty/n_tty.c:2131
2 locks held by getty/4600:
 #0:         (ptrval) (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365
 #1:         (ptrval) (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x321/0x1cc0 drivers/tty/n_tty.c:2131
2 locks held by getty/4601:
 #0:         (ptrval) (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365
 #1:         (ptrval) (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x321/0x1cc0 drivers/tty/n_tty.c:2131
2 locks held by getty/4602:
 #0:         (ptrval) (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365
 #1:         (ptrval) (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x321/0x1cc0 drivers/tty/n_tty.c:2131
2 locks held by getty/4603:
 #0:         (ptrval) (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365
 #1:         (ptrval) (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x321/0x1cc0 drivers/tty/n_tty.c:2131
1 lock held by syz-executor413/4623:
 #0:         (ptrval) (&lo->lo_ctl_mutex/1){+.+.}, at: lo_ioctl+0x8d/0x2130 drivers/block/loop.c:1392

=============================================

NMI backtrace for cpu 1
CPU: 1 PID: 891 Comm: khungtaskd Not tainted 4.17.0-rc6+ #66
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+0x1b9/0x294 lib/dump_stack.c:113
 nmi_cpu_backtrace.cold.4+0x19/0xce lib/nmi_backtrace.c:103
 nmi_trigger_cpumask_backtrace+0x151/0x192 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:138 [inline]
 check_hung_task kernel/hung_task.c:132 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:190 [inline]
 watchdog+0xc10/0xf60 kernel/hung_task.c:249
 kthread+0x345/0x410 kernel/kthread.c:240
 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:412
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0 skipped: idling at native_safe_halt+0x6/0x10 arch/x86/include/asm/irqflags.h:54

Crashes (188):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2018/05/25 20:07 upstream b50694381cfc f48c20b8 .config console log report syz C ci-upstream-kasan-gce
2018/05/25 20:04 upstream b50694381cfc f48c20b8 .config console log report syz C ci-upstream-kasan-gce-root
2018/05/24 12:39 upstream bee797529d7c f48c20b8 .config console log report syz C ci-upstream-kasan-gce
2018/05/24 12:38 upstream bee797529d7c f48c20b8 .config console log report syz C ci-upstream-kasan-gce-root
2018/05/01 06:31 upstream 8188fc8bef8c d5b114b4 .config console log report syz C ci-upstream-kasan-gce-root
2018/05/01 04:14 upstream 8188fc8bef8c d5b114b4 .config console log report syz C ci-upstream-kasan-gce
2018/04/29 13:43 upstream cdface520934 d5a5d045 .config console log report syz C ci-upstream-kasan-gce-root
2018/04/21 05:27 upstream 83beed7b2b26 ca03d688 .config console log report syz C ci-upstream-kasan-gce-root
2018/04/20 20:07 upstream 43f70c960180 cc402841 .config console log report syz C ci-upstream-kasan-gce
2018/06/05 04:13 upstream 910470e03f34 a50d873b .config console log report ci-upstream-kasan-gce
2018/06/02 13:30 upstream 0512e0134582 2f93b54f .config console log report ci-upstream-kasan-gce
2018/06/02 11:44 upstream 0512e0134582 2f93b54f .config console log report ci-upstream-kasan-gce-root
2018/05/30 23:47 upstream d60d61f36b8f 2f93b54f .config console log report ci-upstream-kasan-gce
2018/05/30 14:00 upstream 0044cdeb7313 2f93b54f .config console log report ci-upstream-kasan-gce
2018/05/29 09:12 upstream 786b71f5b754 f48c20b8 .config console log report ci-upstream-kasan-gce-root
2018/05/28 23:27 upstream 786b71f5b754 f48c20b8 .config console log report ci-upstream-kasan-gce
2018/05/28 00:44 upstream 861d9dd37526 f48c20b8 .config console log report ci-upstream-kasan-gce
2018/05/27 15:40 upstream 7fbb6157630f f48c20b8 .config console log report ci-upstream-kasan-gce-root
2018/05/26 22:16 upstream bc2dbc5420e8 f48c20b8 .config console log report ci-upstream-kasan-gce-root
2018/05/25 03:10 upstream d883c6cf3b39 f48c20b8 .config console log report ci-upstream-kasan-gce
2018/05/24 15:21 upstream bee797529d7c f48c20b8 .config console log report ci-upstream-kasan-gce
2018/05/22 13:06 upstream a048a07d7f45 f48c20b8 .config console log report ci-upstream-kasan-gce
2018/05/22 09:13 upstream a048a07d7f45 f48c20b8 .config console log report ci-upstream-kasan-gce
2018/05/22 06:35 upstream 6741c4bb389d f48c20b8 .config console log report ci-upstream-kasan-gce
2018/05/21 10:26 upstream 771c577c23ba f48c20b8 .config console log report ci-upstream-kasan-gce
2018/05/18 03:13 upstream 305bb5521282 738d58ad .config console log report ci-upstream-kasan-gce
2018/05/16 23:41 upstream 21b9f1c7e319 a367c1d7 .config console log report ci-upstream-kasan-gce-root
2018/05/16 10:00 upstream 21b9f1c7e319 75b2448a .config console log report ci-upstream-kasan-gce-root
2018/05/14 04:55 upstream 66e1c94db3cd 481f030c .config console log report ci-upstream-kasan-gce
2018/05/13 14:52 upstream ccda3c4b7777 c05b619d .config console log report ci-upstream-kasan-gce
2018/05/13 13:49 upstream ccda3c4b7777 c05b619d .config console log report ci-upstream-kasan-gce
2018/05/12 04:34 upstream 41e3e1082367 12c7428a .config console log report ci-upstream-kasan-gce
2018/05/09 08:18 upstream 036db8bd9637 12c7428a .config console log report ci-upstream-kasan-gce
2018/05/08 15:23 upstream f142f08bf7ec 045bbd4a .config console log report ci-upstream-kasan-gce
2018/05/07 22:12 upstream 75bc37fefc44 9e0846e8 .config console log report ci-upstream-kasan-gce
2018/05/07 09:05 upstream 701e39d05119 a211da1a .config console log report ci-upstream-kasan-gce-root
2018/05/05 01:54 upstream 625e2001e99e 9ce14f4b .config console log report ci-upstream-kasan-gce
2018/05/05 00:25 upstream 625e2001e99e 9ce14f4b .config console log report ci-upstream-kasan-gce
2018/05/04 18:00 upstream 150426981426 9ce14f4b .config console log report ci-upstream-kasan-gce
2018/05/04 16:15 upstream 150426981426 9ce14f4b .config console log report ci-upstream-kasan-gce
2018/05/04 12:48 upstream 150426981426 9ce14f4b .config console log report ci-upstream-kasan-gce
2018/05/04 05:52 upstream c15f6d8d4715 9ce14f4b .config console log report ci-upstream-kasan-gce
2018/06/04 02:15 upstream 325e14f97e0c 2f93b54f .config console log report ci-upstream-kasan-gce-386
2018/06/03 12:02 upstream 918fe1b31579 2f93b54f .config console log report ci-upstream-kasan-gce-386
2018/06/02 04:44 upstream 0512e0134582 2f93b54f .config console log report ci-upstream-kasan-gce-386
2018/06/01 09:23 upstream dd52cb879063 2f93b54f .config console log report ci-upstream-kasan-gce-386
2018/06/01 01:10 upstream dd52cb879063 2f93b54f .config console log report ci-upstream-kasan-gce-386
2018/05/29 04:25 upstream 786b71f5b754 f48c20b8 .config console log report ci-upstream-kasan-gce-386
2018/05/28 18:34 upstream b04e217704b7 f48c20b8 .config console log report ci-upstream-kasan-gce-386
2018/05/24 02:23 upstream bee797529d7c f48c20b8 .config console log report ci-upstream-kasan-gce-386
2018/05/19 11:39 upstream 73fcb1a370c7 849705db .config console log report ci-upstream-kasan-gce-386
2018/05/17 01:23 upstream e6506eb24187 a367c1d7 .config console log report ci-upstream-kasan-gce-386
2018/05/07 13:02 upstream 75bc37fefc44 a211da1a .config console log report ci-upstream-kasan-gce-386
2018/05/06 00:52 upstream c1c07416cdd4 78b251cb .config console log report ci-upstream-kasan-gce-386
2018/05/04 07:57 upstream c15f6d8d4715 9ce14f4b .config console log report ci-upstream-kasan-gce-386
2018/02/06 20:31 upstream e237f98a9c13 66c15deb .config console log report ci-upstream-kasan-gce-386
2018/07/07 23:12 https://github.com/google/kmsan.git master a00de5aa4da3 ab89aea9 .config console log report ci-upstream-kmsan-gce
2018/07/06 08:33 https://github.com/google/kmsan.git master 9c9df9f275f0 18403e65 .config console log report ci-upstream-kmsan-gce
* Struck through repros no longer work on HEAD.