syzbot


INFO: rcu detected stall in loop_process_work

Status: auto-obsoleted due to no activity on 2024/10/20 21:16
Reported-by: syzbot+a6c2900ead11e8eafc0f@syzkaller.appspotmail.com
First crash: 131d, last: 131d
Similar bugs (1)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: rcu detected stall in loop_process_work block 1 520d 520d 0/28 auto-obsoleted due to no activity on 2023/09/18 06:20

Sample crash report:
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	0-...!: (3 ticks this GP) idle=a004/1/0x4000000000000000 softirq=13545/13545 fqs=1
	(detected by 1, t=10504 jiffies, g=16873, q=788 ncpus=2)
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 3788 Comm: kworker/u4:11 Not tainted 6.1.98-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/07/2024
Workqueue: loop1 loop_workfn
RIP: 0010:__raw_spin_lock_irq include/linux/spinlock_api_smp.h:119 [inline]
RIP: 0010:_raw_spin_lock_irq+0xb8/0x110 kernel/locking/spinlock.c:170
Code: 74 08 4c 89 f7 e8 a8 9f 4c f7 8b 44 24 20 fa a9 00 02 00 00 74 05 e8 97 e1 fb f6 bf 01 00 00 00 e8 3d e7 c8 f6 49 8d 7c 24 18 <31> f6 31 d2 31 c9 41 b8 01 00 00 00 45 31 c9 ff 75 08 e8 31 ee d4
RSP: 0018:ffffc90000007cc0 EFLAGS: 00000002
RAX: 0000000000010003 RBX: 1ffff92000000f9c RCX: ffffffff91c94103
RDX: 0000000080010002 RSI: ffffffff8b3d47c0 RDI: ffff8880b982a4d8
RBP: ffffc90000007d50 R08: ffffffff8179c4bf R09: fffffbfff1ce702e
R10: 0000000000000000 R11: dffffc0000000001 R12: ffff8880b982a4c0
R13: 1ffff92000000f98 R14: ffffc90000007ce0 R15: dffffc0000000000
FS:  0000000000000000(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fc780c64d1c CR3: 000000007cdb8000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <NMI>
 </NMI>
 <IRQ>
 __run_hrtimer kernel/time/hrtimer.c:1690 [inline]
 __hrtimer_run_queues+0x6d3/0xe50 kernel/time/hrtimer.c:1750
 hrtimer_interrupt+0x392/0x980 kernel/time/hrtimer.c:1812
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1095 [inline]
 __sysvec_apic_timer_interrupt+0x156/0x580 arch/x86/kernel/apic/apic.c:1112
 sysvec_apic_timer_interrupt+0x8c/0xb0 arch/x86/kernel/apic/apic.c:1106
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:653
RIP: 0010:__raw_spin_unlock_irq include/linux/spinlock_api_smp.h:160 [inline]
RIP: 0010:_raw_spin_unlock_irq+0x25/0x40 kernel/locking/spinlock.c:202
Code: f1 bc f5 ff 90 53 48 89 fb 48 83 c7 18 48 8b 74 24 08 e8 8e 12 d5 f6 48 89 df e8 f6 4f d6 f6 e8 41 dc fb f6 fb bf 01 00 00 00 <e8> 86 e6 c8 f6 65 8b 05 87 f2 6c 75 85 c0 74 02 5b c3 e8 34 16 6b
RSP: 0018:ffffc90004e67438 EFLAGS: 00000282
RAX: d963f685f883fb00 RBX: ffff888022eca300 RCX: ffffffff816ad6da
RDX: dffffc0000000000 RSI: ffffffff8aec0240 RDI: 0000000000000001
RBP: 1ffff110045d945f R08: dffffc0000000000 R09: fffffbfff2093846
R10: 0000000000000000 R11: dffffc0000000001 R12: ffffea00013a2380
R13: 0000000000000006 R14: ffffea00013a2380 R15: ffff888022eca2f8
 spin_unlock_irq include/linux/spinlock.h:401 [inline]
 filemap_remove_folio+0x10d/0x2e0 mm/filemap.c:256
 truncate_inode_folio+0x59/0x70 mm/truncate.c:195
 shmem_undo_range+0x570/0x2390 mm/shmem.c:942
 shmem_truncate_range mm/shmem.c:1062 [inline]
 shmem_fallocate+0x49b/0x11c0 mm/shmem.c:2787
 lo_fallocate drivers/block/loop.c:322 [inline]
 do_req_filebacked drivers/block/loop.c:488 [inline]
 loop_handle_cmd drivers/block/loop.c:1909 [inline]
 loop_process_work+0x7ea/0x2200 drivers/block/loop.c:1944
 process_one_work+0x8a9/0x11d0 kernel/workqueue.c:2292
 worker_thread+0xa47/0x1200 kernel/workqueue.c:2439
 kthread+0x28d/0x320 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308
 </TASK>
rcu: rcu_preempt kthread timer wakeup didn't happen for 9031 jiffies! g16873 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402
rcu: 	Possible timer handling issue on cpu=0 timer-softirq=10432
rcu: rcu_preempt kthread starved for 9032 jiffies! g16873 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->cpu=0
rcu: 	Unless rcu_preempt kthread gets sufficient CPU time, OOM is now expected behavior.
rcu: RCU grace-period kthread stack dump:
task:rcu_preempt     state:I stack:25816 pid:16    ppid:2      flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5245 [inline]
 __schedule+0x142d/0x4550 kernel/sched/core.c:6558
 schedule+0xbf/0x180 kernel/sched/core.c:6634
 schedule_timeout+0x1b9/0x300 kernel/time/timer.c:1965
 rcu_gp_fqs_loop+0x2d2/0x1150 kernel/rcu/tree.c:1706
 rcu_gp_kthread+0xa3/0x3b0 kernel/rcu/tree.c:1905
 kthread+0x28d/0x320 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 3788 Comm: kworker/u4:11 Not tainted 6.1.98-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/07/2024
Workqueue: loop1 loop_workfn
RIP: 0010:__lock_acquire+0x1aa/0x1f80 kernel/locking/lockdep.c:4959
Code: 89 6c 24 48 0f 84 35 01 00 00 49 8d 9d e0 0a 00 00 83 fe 30 0f 87 18 1b 00 00 48 8d 04 b6 4c 8d 6c c3 f8 4c 89 e8 48 c1 e8 03 <0f> b6 04 10 84 c0 0f 85 2a 16 00 00 48 89 f0 48 83 bc 24 c0 00 00
RSP: 0018:ffffc90000007a80 EFLAGS: 00000802
RAX: 1ffff11004e8bc97 RBX: ffff88802745e420 RCX: 000000000000002c
RDX: dffffc0000000000 RSI: 0000000000000004 RDI: ffffffff8d12ad00
RBP: ffff88802745e418 R08: 0000000000000000 R09: 0000000000000001
R10: 0000000000000000 R11: dffffc0000000001 R12: 0000000000000000
R13: ffff88802745e4b8 R14: ffffffff8d12ad00 R15: 000000000000002c
FS:  0000000000000000(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fc780c64d1c CR3: 000000007cdb8000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <NMI>
 </NMI>
 <IRQ>
 lock_acquire+0x1f8/0x5a0 kernel/locking/lockdep.c:5662
 rcu_lock_acquire include/linux/rcupdate.h:350 [inline]
 rcu_read_lock include/linux/rcupdate.h:791 [inline]
 advance_sched+0x6ec/0x970 net/sched/sch_taprio.c:753
 __run_hrtimer kernel/time/hrtimer.c:1686 [inline]
 __hrtimer_run_queues+0x5e5/0xe50 kernel/time/hrtimer.c:1750
 hrtimer_interrupt+0x392/0x980 kernel/time/hrtimer.c:1812
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1095 [inline]
 __sysvec_apic_timer_interrupt+0x156/0x580 arch/x86/kernel/apic/apic.c:1112
 sysvec_apic_timer_interrupt+0x8c/0xb0 arch/x86/kernel/apic/apic.c:1106
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:653
RIP: 0010:__raw_spin_unlock_irq include/linux/spinlock_api_smp.h:160 [inline]
RIP: 0010:_raw_spin_unlock_irq+0x25/0x40 kernel/locking/spinlock.c:202
Code: f1 bc f5 ff 90 53 48 89 fb 48 83 c7 18 48 8b 74 24 08 e8 8e 12 d5 f6 48 89 df e8 f6 4f d6 f6 e8 41 dc fb f6 fb bf 01 00 00 00 <e8> 86 e6 c8 f6 65 8b 05 87 f2 6c 75 85 c0 74 02 5b c3 e8 34 16 6b
RSP: 0018:ffffc90004e67438 EFLAGS: 00000282
RAX: d963f685f883fb00 RBX: ffff888022eca300 RCX: ffffffff816ad6da
RDX: dffffc0000000000 RSI: ffffffff8aec0240 RDI: 0000000000000001
RBP: 1ffff110045d945f R08: dffffc0000000000 R09: fffffbfff2093846
R10: 0000000000000000 R11: dffffc0000000001 R12: ffffea00013a2380
R13: 0000000000000006 R14: ffffea00013a2380 R15: ffff888022eca2f8
 spin_unlock_irq include/linux/spinlock.h:401 [inline]
 filemap_remove_folio+0x10d/0x2e0 mm/filemap.c:256
 truncate_inode_folio+0x59/0x70 mm/truncate.c:195
 shmem_undo_range+0x570/0x2390 mm/shmem.c:942
 shmem_truncate_range mm/shmem.c:1062 [inline]
 shmem_fallocate+0x49b/0x11c0 mm/shmem.c:2787
 lo_fallocate drivers/block/loop.c:322 [inline]
 do_req_filebacked drivers/block/loop.c:488 [inline]
 loop_handle_cmd drivers/block/loop.c:1909 [inline]
 loop_process_work+0x7ea/0x2200 drivers/block/loop.c:1944
 process_one_work+0x8a9/0x11d0 kernel/workqueue.c:2292
 worker_thread+0xa47/0x1200 kernel/workqueue.c:2439
 kthread+0x28d/0x320 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308
 </TASK>

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/07/12 21:16 linux-6.1.y 266ee8e06d5b eaeb5c15 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in loop_process_work
* Struck through repros no longer work on HEAD.