syzbot


INFO: rcu detected stall in vfs_fallocate

Status: auto-obsoleted due to no activity on 2022/11/19 13:27
Reported-by: syzbot+c44ac76f65d49cdc59d4@syzkaller.appspotmail.com
First crash: 637d, last: 637d
Similar bugs (4)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: rcu detected stall in vfs_fallocate ext4 6 960d 988d 0/26 auto-closed as invalid on 2021/12/01 16:15
upstream INFO: rcu detected stall in vfs_fallocate (3) ext4 1 153d 153d 0/26 auto-obsoleted due to no activity on 2024/02/16 23:28
upstream INFO: rcu detected stall in vfs_fallocate (2) ext4 1 830d 830d 0/26 closed as invalid on 2022/02/08 10:00
linux-4.19 BUG: soft lockup in vfs_fallocate 1 1069d 1069d 0/1 auto-closed as invalid on 2021/09/13 17:50

Sample crash report:
IPVS: ftp: loaded support on port[0] = 21
IPVS: ftp: loaded support on port[0] = 21
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	(detected by 0, t=10502 jiffies, g=121001, q=318)
rcu: All QSes seen, last rcu_preempt kthread activity 10503 (4295027035-4295016532), jiffies_till_next_fqs=1, root ->qsmask 0x0
syz-executor.1  R  running task    27880  9615  11169 0x00000000
Call Trace:
 <IRQ>
 sched_show_task.cold+0x332/0x396 kernel/sched/core.c:5337
 print_other_cpu_stall kernel/rcu/tree.c:1430 [inline]
 check_cpu_stall kernel/rcu/tree.c:1557 [inline]
 __rcu_pending kernel/rcu/tree.c:3293 [inline]
 rcu_pending kernel/rcu/tree.c:3336 [inline]
 rcu_check_callbacks.cold+0xb37/0xe19 kernel/rcu/tree.c:2682
 update_process_times+0x2a/0x70 kernel/time/timer.c:1650
 tick_sched_handle+0x9b/0x180 kernel/time/tick-sched.c:168
 tick_sched_timer+0xfc/0x290 kernel/time/tick-sched.c:1278
 __run_hrtimer kernel/time/hrtimer.c:1465 [inline]
 __hrtimer_run_queues+0x3f6/0xe60 kernel/time/hrtimer.c:1527
 hrtimer_interrupt+0x326/0x9e0 kernel/time/hrtimer.c:1585
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1071 [inline]
 smp_apic_timer_interrupt+0x10c/0x550 arch/x86/kernel/apic/apic.c:1096
 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:894
 </IRQ>
RIP: 0010:__sanitizer_cov_trace_pc+0x0/0x50 kernel/kcov.c:97
Code: ff 48 89 df e8 11 dd 35 00 e9 ab fe ff ff 4c 89 ef e8 04 dd 35 00 e9 23 fe ff ff 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 <48> 8b 34 24 65 48 8b 04 25 c0 df 01 00 65 8b 15 cc 59 9f 7e 81 e2
RSP: 0018:ffff8880515df240 EFLAGS: 00000202 ORIG_RAX: ffffffffffffff13
RAX: 0000000000000002 RBX: 0000000000000001 RCX: ffffffff83771e23
RDX: 0000000000000001 RSI: ffff8880947a2300 RDI: 0000000000000005
RBP: ffffffff88b3e120 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000005 R11: 0000000000000000 R12: 0000000000000000
R13: ffffffff88b3e0e0 R14: dffffc0000000000 R15: 0000000000000000
 check_preemption_disabled+0x3c/0x280 lib/smp_processor_id.c:25
 __pv_queued_spin_lock_slowpath+0xe2/0xae0 kernel/locking/qspinlock.c:389
 pv_queued_spin_lock_slowpath arch/x86/include/asm/paravirt.h:679 [inline]
 queued_spin_lock_slowpath arch/x86/include/asm/qspinlock.h:53 [inline]
 queued_spin_lock include/asm-generic/qspinlock.h:88 [inline]
 do_raw_spin_lock+0x189/0x220 kernel/locking/spinlock_debug.c:113
 spin_lock include/linux/spinlock.h:329 [inline]
 ext4_lock_group fs/ext4/ext4.h:3022 [inline]
 ext4_mb_discard_group_preallocations+0xada/0x12c0 fs/ext4/mballoc.c:3943
 ext4_mb_discard_preallocations fs/ext4/mballoc.c:4478 [inline]
 ext4_mb_new_blocks+0x1d1d/0x4370 fs/ext4/mballoc.c:4593
 ext4_ext_map_blocks+0x2aa2/0x7390 fs/ext4/extents.c:4493
 ext4_map_blocks+0x7a2/0x1a50 fs/ext4/inode.c:657
 ext4_alloc_file_blocks.isra.0+0x2ca/0xa70 fs/ext4/extents.c:4720
 ext4_fallocate+0x7cf/0x2150 fs/ext4/extents.c:5005
 vfs_fallocate+0x487/0x9a0 fs/open.c:308
 ioctl_preallocate+0x186/0x200 fs/ioctl.c:482
 file_ioctl fs/ioctl.c:498 [inline]
 do_vfs_ioctl+0x1060/0x12e0 fs/ioctl.c:688
 ksys_ioctl+0x9b/0xc0 fs/ioctl.c:705
 __do_sys_ioctl fs/ioctl.c:712 [inline]
 __se_sys_ioctl fs/ioctl.c:710 [inline]
 __x64_sys_ioctl+0x6f/0xb0 fs/ioctl.c:710
 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x7ff2e4b77209
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 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ff2e34cb168 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007ff2e4c8a030 RCX: 00007ff2e4b77209
RDX: 0000000020000040 RSI: 000000004030582a RDI: 0000000000000005
RBP: 00007ff2e4bd1161 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffd4c88ccef R14: 00007ff2e34cb300 R15: 0000000000022000
rcu: rcu_preempt kthread starved for 10553 jiffies! g121001 f0x2 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=1
rcu: RCU grace-period kthread stack dump:
rcu_preempt     R  running task    29208    10      2 0x80000000
Call Trace:
 context_switch kernel/sched/core.c:2828 [inline]
 __schedule+0x887/0x2040 kernel/sched/core.c:3517
 schedule+0x8d/0x1b0 kernel/sched/core.c:3561
 schedule_timeout+0x4cf/0xfe0 kernel/time/timer.c:1818
 rcu_gp_kthread+0xdad/0x21c0 kernel/rcu/tree.c:2202
 kthread+0x33f/0x460 kernel/kthread.c:259
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2022/07/22 13:26 linux-4.19.y 3f8a27f9e27b 22343af4 .config console log report info ci2-linux-4-19 INFO: rcu detected stall in vfs_fallocate
* Struck through repros no longer work on HEAD.