syzbot


INFO: rcu detected stall in check_preemption_disabled

Status: auto-closed as invalid on 2020/08/07 05:10
Reported-by: syzbot+570c3bbb2b164d60094a@syzkaller.appspotmail.com
First crash: 887d, last: 852d
similar bugs (1):
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: rcu detected stall in check_preemption_disabled 1 610d 610d 0/23 auto-closed as invalid on 2021/03/07 11:58

Sample crash report:
EXT4-fs (loop0): feature flags set on rev 0 fs, running e2fsck is recommended
EXT4-fs (loop0): ext4_check_descriptors: Block bitmap for group 0 overlaps superblock
rcu: INFO: rcu_preempt self-detected stall on CPU
rcu: 	1-...!: (10500 ticks this GP) idle=0fe/1/0x4000000000000004 softirq=178219/178219 fqs=0 
rcu: 	 (t=10501 jiffies g=200873 q=190)
rcu: rcu_preempt kthread starved for 10502 jiffies! g200873 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=1
rcu: RCU grace-period kthread stack dump:
rcu_preempt     R  running task    29136    10      2 0x80000000
Call Trace:
 schedule+0x8d/0x1b0 kernel/sched/core.c:3559
 schedule_timeout+0x4d1/0xf20 kernel/time/timer.c:1806
 rcu_gp_kthread+0xcee/0x2060 kernel/rcu/tree.c:2202
 kthread+0x34a/0x420 kernel/kthread.c:246
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415
NMI backtrace for cpu 1
CPU: 1 PID: 1140 Comm: syz-executor.2 Not tainted 4.19.114-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x188/0x20d lib/dump_stack.c:118
 nmi_cpu_backtrace.cold+0x63/0xa2 lib/nmi_backtrace.c:101
 nmi_trigger_cpumask_backtrace+0x1a6/0x1eb lib/nmi_backtrace.c:62
 trigger_single_cpu_backtrace include/linux/nmi.h:164 [inline]
 rcu_dump_cpu_stacks+0x170/0x1bb kernel/rcu/tree.c:1340
 print_cpu_stall kernel/rcu/tree.c:1478 [inline]
 check_cpu_stall kernel/rcu/tree.c:1550 [inline]
 __rcu_pending kernel/rcu/tree.c:3293 [inline]
 rcu_pending kernel/rcu/tree.c:3336 [inline]
 rcu_check_callbacks.cold+0x634/0xddc kernel/rcu/tree.c:2682
 update_process_times+0x2a/0x70 kernel/time/timer.c:1638
 tick_sched_handle+0x9b/0x180 kernel/time/tick-sched.c:168
 tick_sched_timer+0x42/0x130 kernel/time/tick-sched.c:1278
 __run_hrtimer kernel/time/hrtimer.c:1401 [inline]
 __hrtimer_run_queues+0x2fc/0xd50 kernel/time/hrtimer.c:1463
 hrtimer_interrupt+0x312/0x770 kernel/time/hrtimer.c:1521
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1067 [inline]
 smp_apic_timer_interrupt+0x10c/0x550 arch/x86/kernel/apic/apic.c:1092
 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:893
RIP: 0010:__sanitizer_cov_trace_pc+0x0/0x50 kernel/kcov.c:97
Code: 48 c7 c7 00 2c 6e 87 4c 89 25 ec f7 05 0a 41 bc f4 ff ff ff e8 5a 1d eb ff 48 c7 05 d6 f7 05 0a 00 00 00 00 e9 24 ec ff ff 90 <48> 8b 34 24 65 48 8b 04 25 40 ee 01 00 65 8b 15 4c 49 9a 7e 81 e2
RSP: 0018:ffff8880ae707cc8 EFLAGS: 00000206 ORIG_RAX: ffffffffffffff13
RAX: 0000000000000103 RBX: 0000000000000103 RCX: ffffffff83564e63
RDX: 0000000000000103 RSI: 0000000000000000 RDI: 0000000000000005
RBP: ffffffff87aafcc0 R08: ffff888083c402c0 R09: 0000000000000000
R10: ffff888083c40b40 R11: ffffffff8b1c8aa0 R12: 0000000000000001
R13: ffffffff87aafc80 R14: 0000000000000000 R15: ffff88808447cd58
 check_preemption_disabled+0x3c/0x280 lib/smp_processor_id.c:15
 rcu_dynticks_curr_cpu_in_eqs+0x12/0xa0 kernel/rcu/tree.c:348
 rcu_is_watching+0xc/0x20 kernel/rcu/tree.c:1025
 rcu_read_lock_sched_held+0x89/0x130 kernel/rcu/update.c:113
 trace_timer_expire_entry include/trace/events/timer.h:90 [inline]
 call_timer_fn+0x65d/0x700 kernel/time/timer.c:1325
 expire_timers kernel/time/timer.c:1363 [inline]
 __run_timers kernel/time/timer.c:1684 [inline]
 __run_timers kernel/time/timer.c:1652 [inline]
 run_timer_softirq+0x5d0/0x1540 kernel/time/timer.c:1697
 __do_softirq+0x26c/0x93c kernel/softirq.c:292
 invoke_softirq kernel/softirq.c:372 [inline]
 irq_exit+0x17b/0x1c0 kernel/softirq.c:412
 exiting_irq arch/x86/include/asm/apic.h:544 [inline]
 smp_apic_timer_interrupt+0x136/0x550 arch/x86/kernel/apic/apic.c:1094
 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:893
 </IRQ>
RIP: 0010:arch_local_irq_restore arch/x86/include/asm/paravirt.h:789 [inline]
RIP: 0010:lock_release+0x42b/0x820 kernel/locking/lockdep.c:3925
Code: 7c 08 00 00 00 00 00 00 48 c1 e8 03 80 3c 10 00 0f 85 e4 02 00 00 48 83 3d 79 ab 62 07 00 0f 84 36 02 00 00 48 8b 3c 24 57 9d <0f> 1f 44 00 00 48 b8 00 00 00 00 00 fc ff df 48 c7 04 03 00 00 00
RSP: 0018:ffff88821268f8e0 EFLAGS: 00000286 ORIG_RAX: ffffffffffffff13
RAX: 1ffffffff1164ad1 RBX: 1ffff110424d1f20 RCX: 1ffff11010788166
RDX: dffffc0000000000 RSI: 0000000000000001 RDI: 0000000000000286
RBP: ffff888083c402c0 R08: 0000000000000000 R09: 0000000000000000
R10: ffffed10424d1f22 R11: 0000000000000003 R12: ffffffff81a7b5a4
R13: 0000000000000003 R14: ffff888083c402c0 R15: 0000000000000001
 __raw_spin_unlock include/linux/spinlock_api_smp.h:150 [inline]
 _raw_spin_unlock+0x17/0x40 kernel/locking/spinlock.c:176
 spin_unlock include/linux/spinlock.h:369 [inline]
 chrdev_open+0xc4/0x5c0 fs/char_dev.c:411
 do_dentry_open+0x4a8/0x1160 fs/open.c:796
 do_last fs/namei.c:3421 [inline]
 path_openat+0x1031/0x4200 fs/namei.c:3537
 do_filp_open+0x1a1/0x280 fs/namei.c:3567
 do_sys_open+0x3c0/0x500 fs/open.c:1085
 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x416621
Code: 75 14 b8 02 00 00 00 0f 05 48 3d 01 f0 ff ff 0f 83 04 19 00 00 c3 48 83 ec 08 e8 0a fa ff ff 48 89 04 24 b8 02 00 00 00 0f 05 <48> 8b 3c 24 48 89 c2 e8 53 fa ff ff 48 89 d0 48 83 c4 08 48 3d 01
RSP: 002b:00007f4283c1a7a0 EFLAGS: 00000293 ORIG_RAX: 0000000000000002
RAX: ffffffffffffffda RBX: 6666666666666667 RCX: 0000000000416621
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 00007f4283c1a850
RBP: 000000000076bf00 R08: 000000000000000f R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000293 R12: 00000000ffffffff
R13: 0000000000000c06 R14: 00000000004ce31e R15: 000000000076bf0c
EXT4-fs (loop0): ext4_check_descriptors: Inode bitmap for group 0 overlaps superblock
EXT4-fs (loop0): ext4_check_descriptors: Inode table for group 0 overlaps superblock
EXT4-fs: failed to create workqueue
EXT4-fs (loop0): mount failed

Crashes (2):
Manager Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Title
ci2-linux-4-19 2020/04/09 05:10 linux-4.19.y dda0e2920330 a8c6a3f8 .config log report
ci2-linux-4-19 2020/03/05 09:58 linux-4.19.y a083db76118d 576fb9bc .config log report