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INFO: rcu detected stall in vfs_fallocate (2)

Status: closed as invalid on 2022/02/08 10:00
Subsystems: ext4
[Documentation on labels]
First crash: 836d, last: 836d
▶ ▼ 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 966d 993d 0/26 auto-closed as invalid on 2021/12/01 16:15
linux-4.19 INFO: rcu detected stall in vfs_fallocate 1 643d 643d 0/1 auto-obsoleted due to no activity on 2022/11/19 13:27
upstream INFO: rcu detected stall in vfs_fallocate (3) ext4 1 158d 158d 0/26 auto-obsoleted due to no activity on 2024/02/16 23:28
linux-4.19 BUG: soft lockup in vfs_fallocate 1 1074d 1074d 0/1 auto-closed as invalid on 2021/09/13 17:50

Sample crash report:
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	0-...!: (1 ticks this GP) idle=353/1/0x4000000000000002 softirq=111257/111257 fqs=0 
	(detected by 1, t=10502 jiffies, g=184813, q=221)
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 27245 Comm: syz-executor.0 Not tainted 5.16.0-rc8-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:default_send_IPI_self+0x5d/0xe0 arch/x86/kernel/apic/ipi.c:243
Code: 1a f3 90 0f b6 45 00 84 c0 74 04 3c 03 7e 76 8b 04 25 00 c3 5f ff f6 c4 10 75 e6 81 cb 00 00 04 00 89 df 89 3c 25 00 c3 5f ff <5b> 5d c3 48 c7 c0 60 2a 57 8b 48 ba 00 00 00 00 00 fc ff df 48 c1
RSP: 0018:ffffc90000007a48 EFLAGS: 00000006
RAX: 00000000000400f6 RBX: 00000000000400f6 RCX: ffffffff812a1153
RDX: 1ffffffff16ae55b RSI: 0000000000000008 RDI: 00000000000400f6
RBP: fffffbffffebf860 R08: 0000000000000000 R09: ffffffff8d9206c7
R10: fffffbfff1b240d8 R11: 0000000000000000 R12: 0000000000000000
R13: ffff8880b9c3a930 R14: 0000000000000000 R15: ffffe8ffffcfa000
FS:  00007f01e0ee2700(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b2e421000 CR3: 000000005627f000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000600
Call Trace:
 <IRQ>
 arch_irq_work_raise+0x92/0x110 arch/x86/kernel/irq_work.c:31
 __irq_work_queue_local+0x15a/0x1b0 kernel/irq_work.c:102
 irq_work_queue_on+0x146/0x160 kernel/irq_work.c:165
 rcu_read_unlock_special kernel/rcu/tree_plugin.h:663 [inline]
 __rcu_read_unlock+0x436/0x570 kernel/rcu/tree_plugin.h:422
 rcu_read_unlock include/linux/rcupdate.h:720 [inline]
 BPF_PROG_RUN_ARRAY include/linux/bpf.h:1364 [inline]
 trace_call_bpf+0x2f9/0x5f0 kernel/trace/bpf_trace.c:127
 perf_trace_run_bpf_submit+0x91/0x210 kernel/events/core.c:9708
 perf_trace_preemptirq_template+0x296/0x460 include/trace/events/preemptirq.h:14
 trace_irq_enable_rcuidle include/trace/events/preemptirq.h:40 [inline]
 trace_irq_enable_rcuidle include/trace/events/preemptirq.h:40 [inline]
 trace_hardirqs_on+0x156/0x1c0 kernel/trace/trace_preemptirq.c:44
 asm_sysvec_irq_work+0x12/0x20 arch/x86/include/asm/idtentry.h:664
RIP: 0010:get_current arch/x86/include/asm/current.h:15 [inline]
RIP: 0010:__rcu_read_unlock+0xc4/0x570 kernel/rcu/tree_plugin.h:425
Code: b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 0f b6 04 02 84 c0 74 08 3c 03 0f 8e b6 01 00 00 8b 85 40 04 00 00 85 c0 75 54 <65> 48 8b 1c 25 40 70 02 00 48 8d bb 3c 04 00 00 48 b8 00 00 00 00
RSP: 0018:ffffc90000007dc0 EFLAGS: 00000206
RAX: 0000000000000002 RBX: ffff8880b9c3a900 RCX: 1ffffffff1ffaa2e
RDX: 0000000000000000 RSI: 0000000000000101 RDI: 0000000000000000
RBP: ffffffff8bb8cb00 R08: 0000000000000001 R09: ffffffff8ff9ba9f
R10: 0000000000000001 R11: 0000000000000000 R12: 0000000000000001
R13: ffffffff8544cb00 R14: 0000000000000200 R15: ffffffff854479b0
 rcu_read_unlock include/linux/rcupdate.h:720 [inline]
 ieee80211_iterate_active_interfaces_atomic+0x92/0x180 net/mac80211/util.c:831
 mac80211_hwsim_beacon+0xcd/0x1c0 drivers/net/wireless/mac80211_hwsim.c:1861
 __run_hrtimer kernel/time/hrtimer.c:1685 [inline]
 __hrtimer_run_queues+0x609/0xe50 kernel/time/hrtimer.c:1749
 hrtimer_run_softirq+0x17b/0x360 kernel/time/hrtimer.c:1766
 __do_softirq+0x29b/0x9c2 kernel/softirq.c:558
 invoke_softirq kernel/softirq.c:432 [inline]
 __irq_exit_rcu+0x123/0x180 kernel/softirq.c:637
 irq_exit_rcu+0x5/0x20 kernel/softirq.c:649
 sysvec_apic_timer_interrupt+0x93/0xc0 arch/x86/kernel/apic/apic.c:1097
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:638
RIP: 0010:__es_insert_extent+0x0/0x13e0 fs/ext4/extents_status.c:758
Code: ee e8 a4 8e 69 ff 45 85 ed 0f 85 68 ff ff ff eb 8e 41 bc 01 00 00 00 e9 29 ff ff ff 66 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 00 <41> 57 41 56 41 55 41 54 55 53 48 89 fb 48 83 ec 70 48 89 7c 24 48
RSP: 0018:ffffc90002b8f728 EFLAGS: 00000293
RAX: 0000000000000000 RBX: 000000002d202000 RCX: 0000000000000000
RDX: ffff888044423a00 RSI: ffffc90002b8f788 RDI: ffff888041256650
RBP: ffff888041256650 R08: 0000000000000000 R09: 0000000000000000
R10: ffffffff820e667d R11: 0000000000000000 R12: 0000000000000000
R13: ffff8880412563b0 R14: ffffc90002b8f788 R15: ffffed100824accf
 ext4_es_insert_extent+0x303/0xc80 fs/ext4/extents_status.c:855
 ext4_map_blocks+0x8de/0x17d0 fs/ext4/inode.c:706
 ext4_alloc_file_blocks.isra.0+0x2c1/0xae0 fs/ext4/extents.c:4472
 ext4_fallocate+0x488/0x41d0 fs/ext4/extents.c:4753
 vfs_fallocate+0x48d/0xe10 fs/open.c:307
 ioctl_preallocate+0x18e/0x200 fs/ioctl.c:294
 file_ioctl fs/ioctl.c:334 [inline]
 do_vfs_ioctl+0x1144/0x15d0 fs/ioctl.c:853
 __do_sys_ioctl fs/ioctl.c:872 [inline]
 __se_sys_ioctl fs/ioctl.c:860 [inline]
 __x64_sys_ioctl+0x108/0x200 fs/ioctl.c:860
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x7f01e256ce99
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 bc ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f01e0ee2168 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f01e267ff60 RCX: 00007f01e256ce99
RDX: 0000000020000040 RSI: 000000004030582a RDI: 0000000000000005
RBP: 00007f01e25c6ff1 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fffff4b526f R14: 00007f01e0ee2300 R15: 0000000000022000
 </TASK>
rcu: rcu_preempt kthread timer wakeup didn't happen for 10501 jiffies! g184813 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402
rcu: 	Possible timer handling issue on cpu=0 timer-softirq=77169
rcu: rcu_preempt kthread starved for 10502 jiffies! g184813 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:28680 pid:   14 ppid:     2 flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:4972 [inline]
 __schedule+0xa9a/0x4900 kernel/sched/core.c:6253
 schedule+0xd2/0x260 kernel/sched/core.c:6326
 schedule_timeout+0x14a/0x2a0 kernel/time/timer.c:1881
 rcu_gp_fqs_loop+0x186/0x810 kernel/rcu/tree.c:1955
 rcu_gp_kthread+0x1de/0x320 kernel/rcu/tree.c:2128
 kthread+0x405/0x4f0 kernel/kthread.c:327
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
 </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: 27245 Comm: syz-executor.0 Not tainted 5.16.0-rc8-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:write_comp_data kernel/kcov.c:221 [inline]
RIP: 0010:__sanitizer_cov_trace_const_cmp1+0x15/0x80 kernel/kcov.c:273
Code: 00 48 89 4c 38 f0 4e 89 54 c8 20 48 89 10 c3 66 0f 1f 44 00 00 53 41 89 fb 41 89 f1 bf 03 00 00 00 65 48 8b 0c 25 40 70 02 00 <48> 89 ce 4c 8b 54 24 08 e8 4e f7 ff ff 84 c0 74 51 48 8b 81 88 15
RSP: 0018:ffffc90000007ae0 EFLAGS: 00000046
RAX: 0000000000000001 RBX: 0000000000000001 RCX: ffff888044423a00
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000003
RBP: ffff88806d1c9528 R08: 0000000000000040 R09: 0000000000000001
R10: ffffffff818121e4 R11: 0000000000000000 R12: 00000000ffffffea
R13: dffffc0000000000 R14: 0000000000000000 R15: ffffe8ffffcfa000
FS:  00007f01e0ee2700(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b2e421000 CR3: 000000005627f000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000600
Call Trace:
 <IRQ>
 rcu_read_unlock include/linux/rcupdate.h:717 [inline]
 BPF_PROG_RUN_ARRAY include/linux/bpf.h:1364 [inline]
 trace_call_bpf+0x2e7/0x5f0 kernel/trace/bpf_trace.c:127
 perf_trace_run_bpf_submit+0x91/0x210 kernel/events/core.c:9708
 perf_trace_preemptirq_template+0x296/0x460 include/trace/events/preemptirq.h:14
 trace_irq_enable_rcuidle include/trace/events/preemptirq.h:40 [inline]
 trace_irq_enable_rcuidle include/trace/events/preemptirq.h:40 [inline]
 trace_hardirqs_on+0x156/0x1c0 kernel/trace/trace_preemptirq.c:44
 asm_sysvec_irq_work+0x12/0x20 arch/x86/include/asm/idtentry.h:664
RIP: 0010:get_current arch/x86/include/asm/current.h:15 [inline]
RIP: 0010:__rcu_read_unlock+0xc4/0x570 kernel/rcu/tree_plugin.h:425
Code: b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 0f b6 04 02 84 c0 74 08 3c 03 0f 8e b6 01 00 00 8b 85 40 04 00 00 85 c0 75 54 <65> 48 8b 1c 25 40 70 02 00 48 8d bb 3c 04 00 00 48 b8 00 00 00 00
RSP: 0018:ffffc90000007dc0 EFLAGS: 00000206
RAX: 0000000000000002 RBX: ffff8880b9c3a900 RCX: 1ffffffff1ffaa2e
RDX: 0000000000000000 RSI: 0000000000000101 RDI: 0000000000000000
RBP: ffffffff8bb8cb00 R08: 0000000000000001 R09: ffffffff8ff9ba9f
R10: 0000000000000001 R11: 0000000000000000 R12: 0000000000000001
R13: ffffffff8544cb00 R14: 0000000000000200 R15: ffffffff854479b0
 rcu_read_unlock include/linux/rcupdate.h:720 [inline]
 ieee80211_iterate_active_interfaces_atomic+0x92/0x180 net/mac80211/util.c:831
 mac80211_hwsim_beacon+0xcd/0x1c0 drivers/net/wireless/mac80211_hwsim.c:1861
 __run_hrtimer kernel/time/hrtimer.c:1685 [inline]
 __hrtimer_run_queues+0x609/0xe50 kernel/time/hrtimer.c:1749
 hrtimer_run_softirq+0x17b/0x360 kernel/time/hrtimer.c:1766
 __do_softirq+0x29b/0x9c2 kernel/softirq.c:558
 invoke_softirq kernel/softirq.c:432 [inline]
 __irq_exit_rcu+0x123/0x180 kernel/softirq.c:637
 irq_exit_rcu+0x5/0x20 kernel/softirq.c:649
 sysvec_apic_timer_interrupt+0x93/0xc0 arch/x86/kernel/apic/apic.c:1097
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:638
RIP: 0010:__es_insert_extent+0x0/0x13e0 fs/ext4/extents_status.c:758
Code: ee e8 a4 8e 69 ff 45 85 ed 0f 85 68 ff ff ff eb 8e 41 bc 01 00 00 00 e9 29 ff ff ff 66 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 00 <41> 57 41 56 41 55 41 54 55 53 48 89 fb 48 83 ec 70 48 89 7c 24 48
RSP: 0018:ffffc90002b8f728 EFLAGS: 00000293
RAX: 0000000000000000 RBX: 000000002d202000 RCX: 0000000000000000
RDX: ffff888044423a00 RSI: ffffc90002b8f788 RDI: ffff888041256650
RBP: ffff888041256650 R08: 0000000000000000 R09: 0000000000000000
R10: ffffffff820e667d R11: 0000000000000000 R12: 0000000000000000
R13: ffff8880412563b0 R14: ffffc90002b8f788 R15: ffffed100824accf
 ext4_es_insert_extent+0x303/0xc80 fs/ext4/extents_status.c:855
 ext4_map_blocks+0x8de/0x17d0 fs/ext4/inode.c:706
 ext4_alloc_file_blocks.isra.0+0x2c1/0xae0 fs/ext4/extents.c:4472
 ext4_fallocate+0x488/0x41d0 fs/ext4/extents.c:4753
 vfs_fallocate+0x48d/0xe10 fs/open.c:307
 ioctl_preallocate+0x18e/0x200 fs/ioctl.c:294
 file_ioctl fs/ioctl.c:334 [inline]
 do_vfs_ioctl+0x1144/0x15d0 fs/ioctl.c:853
 __do_sys_ioctl fs/ioctl.c:872 [inline]
 __se_sys_ioctl fs/ioctl.c:860 [inline]
 __x64_sys_ioctl+0x108/0x200 fs/ioctl.c:860
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x7f01e256ce99
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 bc ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f01e0ee2168 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f01e267ff60 RCX: 00007f01e256ce99
RDX: 0000000020000040 RSI: 000000004030582a RDI: 0000000000000005
RBP: 00007f01e25c6ff1 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fffff4b526f R14: 00007f01e0ee2300 R15: 0000000000022000
 </TASK>
----------------
Code disassembly (best guess):
   0:	1a f3                	sbb    %bl,%dh
   2:	90                   	nop
   3:	0f b6 45 00          	movzbl 0x0(%rbp),%eax
   7:	84 c0                	test   %al,%al
   9:	74 04                	je     0xf
   b:	3c 03                	cmp    $0x3,%al
   d:	7e 76                	jle    0x85
   f:	8b 04 25 00 c3 5f ff 	mov    0xffffffffff5fc300,%eax
  16:	f6 c4 10             	test   $0x10,%ah
  19:	75 e6                	jne    0x1
  1b:	81 cb 00 00 04 00    	or     $0x40000,%ebx
  21:	89 df                	mov    %ebx,%edi
  23:	89 3c 25 00 c3 5f ff 	mov    %edi,0xffffffffff5fc300
* 2a:	5b                   	pop    %rbx <-- trapping instruction
  2b:	5d                   	pop    %rbp
  2c:	c3                   	retq
  2d:	48 c7 c0 60 2a 57 8b 	mov    $0xffffffff8b572a60,%rax
  34:	48 ba 00 00 00 00 00 	movabs $0xdffffc0000000000,%rdx
  3b:	fc ff df
  3e:	48                   	rex.W
  3f:	c1                   	.byte 0xc1

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2022/01/10 12:22 bpf-next 242db6ce976a 2ca0d385 .config console log report info ci-upstream-bpf-next-kasan-gce INFO: rcu detected stall in vfs_fallocate
* Struck through repros no longer work on HEAD.