syzbot


INFO: task hung in __bread_gfp (4)

Status: auto-obsoleted due to no activity on 2023/07/25 23:59
Subsystems: reiserfs
[Documentation on labels]
Reported-by: syzbot+9053a1cf1723c8bcce6c@syzkaller.appspotmail.com
First crash: 454d, last: 389d
Cause bisection: failed (error log, bisect log)
  
Discussions (1)
Title Replies (including bot) Last reply
[syzbot] [reiserfs?] INFO: task hung in __bread_gfp (4) 0 (1) 2022/12/25 06:15
Similar bugs (4)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: task hung in __bread_gfp (3) fs 1 864d 864d 0/26 auto-closed as invalid on 2022/02/04 04:37
upstream INFO: task hung in __bread_gfp exfat 4 2081d 2176d 0/26 auto-closed as invalid on 2019/02/22 10:29
android-49 INFO: task hung in __bread_gfp 2 2162d 2176d 0/3 auto-closed as invalid on 2019/02/22 14:34
upstream INFO: task hung in __bread_gfp (2) jfs 5 1398d 1404d 0/26 auto-closed as invalid on 2020/07/20 01:01
Last patch testing requests (4)
Created Duration User Patch Repo Result
2023/07/25 23:18 22m retest repro linux-next OK log
2023/07/25 23:18 21m retest repro linux-next OK log
2023/05/16 22:30 12m retest repro linux-next error OK
2023/05/16 22:30 12m retest repro linux-next error OK

Sample crash report:
INFO: task syz-executor419:5082 blocked for more than 143 seconds.
      Not tainted 6.2.0-next-20230223-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor419 state:D stack:27440 pid:5082  ppid:5081   flags:0x00004004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5304 [inline]
 __schedule+0x24b4/0x5ac0 kernel/sched/core.c:6622
 schedule+0xde/0x1a0 kernel/sched/core.c:6698
 io_schedule+0xbe/0x130 kernel/sched/core.c:8884
 bit_wait_io+0x16/0xe0 kernel/sched/wait_bit.c:209
 __wait_on_bit+0x64/0x180 kernel/sched/wait_bit.c:49
 out_of_line_wait_on_bit+0xd9/0x110 kernel/sched/wait_bit.c:64
 wait_on_bit_io include/linux/wait_bit.h:101 [inline]
 __wait_on_buffer fs/buffer.c:123 [inline]
 wait_on_buffer include/linux/buffer_head.h:388 [inline]
 __bread_slow fs/buffer.c:1221 [inline]
 __bread_gfp+0x29e/0x330 fs/buffer.c:1413
 sb_bread include/linux/buffer_head.h:341 [inline]
 read_super_block+0x83/0x930 fs/reiserfs/super.c:1604
 reiserfs_fill_super+0x75a/0x2ea0 fs/reiserfs/super.c:1959
 mount_bdev+0x351/0x410 fs/super.c:1371
 legacy_get_tree+0x109/0x220 fs/fs_context.c:610
 vfs_get_tree+0x8d/0x350 fs/super.c:1501
 do_new_mount fs/namespace.c:3042 [inline]
 path_mount+0x1342/0x1e40 fs/namespace.c:3372
 do_mount fs/namespace.c:3385 [inline]
 __do_sys_mount fs/namespace.c:3594 [inline]
 __se_sys_mount fs/namespace.c:3571 [inline]
 __x64_sys_mount+0x283/0x300 fs/namespace.c:3571
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x39/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7f04d36f13d9
RSP: 002b:00007ffed770c1a8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f04d36f13d9
RDX: 00000000200003c0 RSI: 0000000020000380 RDI: 0000000020000340
RBP: 0000000000000000 R08: 0000000000000000 R09: 00007ffed770c348
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f04d36b06f0
R13: 431bde82d7b634db R14: 0000000000000000 R15: 0000000000000000
 </TASK>

Showing all locks held in the system:
1 lock held by rcu_tasks_kthre/12:
 #0: ffffffff8c796bf0 (rcu_tasks.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x31/0xd80 kernel/rcu/tasks.h:510
1 lock held by rcu_tasks_trace/13:
 #0: ffffffff8c7968f0 (rcu_tasks_trace.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x31/0xd80 kernel/rcu/tasks.h:510
1 lock held by khungtaskd/28:
 #0: ffffffff8c797740 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x51/0x390 kernel/locking/lockdep.c:6495
2 locks held by getty/4758:
 #0: ffff88802c224098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x26/0x80 drivers/tty/tty_ldisc.c:244
 #1: ffffc900015a02f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0xef4/0x13e0 drivers/tty/n_tty.c:2177
1 lock held by syz-executor419/5082:
 #0: ffff88807bbce0e0 (&type->s_umount_key#25/1){+.+.}-{3:3}, at: alloc_super+0x22e/0xb60 fs/super.c:228

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

NMI backtrace for cpu 0
CPU: 0 PID: 28 Comm: khungtaskd Not tainted 6.2.0-next-20230223-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/16/2023
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0xd9/0x150 lib/dump_stack.c:106
 nmi_cpu_backtrace+0x316/0x3e0 lib/nmi_backtrace.c:113
 nmi_trigger_cpumask_backtrace+0x3a7/0x460 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:222 [inline]
 watchdog+0xe94/0x11e0 kernel/hung_task.c:379
 kthread+0x2e8/0x3a0 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308
 </TASK>
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1 skipped: idling at native_safe_halt arch/x86/include/asm/irqflags.h:48 [inline]
NMI backtrace for cpu 1 skipped: idling at arch_safe_halt arch/x86/include/asm/irqflags.h:86 [inline]
NMI backtrace for cpu 1 skipped: idling at acpi_safe_halt+0x40/0x50 drivers/acpi/processor_idle.c:112

Crashes (3):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2023/02/24 05:30 linux-next 0222aa9800b2 9e2ebb3c .config strace log report syz C [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root INFO: task hung in __bread_gfp
2022/12/21 06:09 linux-next e45fb347b630 d3e76707 .config strace log report syz C [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root INFO: task hung in __bread_gfp
2022/12/21 01:30 linux-next e45fb347b630 d3e76707 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root INFO: task hung in __bread_gfp
* Struck through repros no longer work on HEAD.