syzbot


INFO: rcu detected stall in ext4_lazyinit_thread

Status: auto-obsoleted due to no activity on 2024/10/21 09:39
Subsystems: ext4
[Documentation on labels]
First crash: 205d, last: 205d
Similar bugs (2)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-6.1 INFO: rcu detected stall in ext4_lazyinit_thread 1 145d 145d 0/3 auto-obsoleted due to no activity on 2024/12/29 16:44
android-5-15 BUG: soft lockup in ext4_lazyinit_thread 1 231d 231d 0/2 auto-obsoleted due to no activity on 2024/09/24 15:57

Sample crash report:
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	1-...!: (1 GPs behind) idle=e3c4/1/0x4000000000000000 softirq=52840/52845 fqs=19
rcu: 	         hardirqs   softirqs   csw/system
rcu: 	 number:        2         50            6
rcu: 	cputime:        0         18           10   ==> 105040(ms)
rcu: 	(detected by 0, t=10502 jiffies, g=68089, q=1109 ncpus=2)
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 11117 Comm: ext4lazyinit Not tainted 6.10.0-syzkaller-12030-g66ebbdfdeb09 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/27/2024
RIP: 0010:advance_sched+0x992/0xca0 net/sched/sch_taprio.c:980
Code: 00 74 0b 48 89 fd e8 0d c6 62 f8 48 89 ef 48 8b 44 24 10 48 89 07 48 89 df 48 8b 34 24 4c 89 f2 e8 23 03 00 00 48 8b 44 24 78 <42> 80 3c 20 00 74 0a 48 8b 7c 24 70 e8 dd c5 62 f8 4d 89 77 e8 48
RSP: 0018:ffffc90000a18c90 EFLAGS: 00000082
RAX: 1ffff11003f8c465 RBX: ffff88801fc622c0 RCX: ffff88801a755a00
RDX: 0000000000010002 RSI: 0000000000000004 RDI: ffff88802df89484
RBP: ffff88802df894c8 R08: ffff88802df89487 R09: 1ffff11005bf1290
R10: dffffc0000000000 R11: ffffed1005bf1291 R12: dffffc0000000000
R13: ffff88802df89408 R14: ffff88802df89400 R15: ffff88801fc62340
FS:  0000000000000000(0000) GS:ffff8880b9500000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f0da5cd0ab8 CR3: 0000000020082000 CR4: 0000000000350ef0
Call Trace:
 <NMI>
 </NMI>
 <IRQ>
 __run_hrtimer kernel/time/hrtimer.c:1689 [inline]
 __hrtimer_run_queues+0x59d/0xd50 kernel/time/hrtimer.c:1753
 hrtimer_interrupt+0x396/0x990 kernel/time/hrtimer.c:1815
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1032 [inline]
 __sysvec_apic_timer_interrupt+0x112/0x3f0 arch/x86/kernel/apic/apic.c:1049
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1043 [inline]
 sysvec_apic_timer_interrupt+0xa1/0xc0 arch/x86/kernel/apic/apic.c:1043
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:console_flush_all+0xaad/0xfd0 kernel/printk/printk.c:3055
Code: ff ff e8 f6 dd 1f 00 90 0f 0b 90 e9 d8 f8 ff ff e8 e8 dd 1f 00 e8 c3 3e 1d 0a 4d 85 f6 74 b6 e8 d9 dd 1f 00 fb 48 8b 44 24 70 <42> 0f b6 04 38 84 c0 48 8b 7c 24 30 0f 85 22 02 00 00 0f b6 1f 31
RSP: 0018:ffffc90003db74c0 EFLAGS: 00000293
RAX: 1ffff920007b6ee4 RBX: 0000000000000000 RCX: ffff88801a755a00
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc90003db7670 R08: ffffffff8173a544 R09: 1ffffffff2600514
R10: dffffc0000000000 R11: fffffbfff2600515 R12: ffffffff8eb30bd8
R13: ffffffff8eb30b80 R14: 0000000000000200 R15: dffffc0000000000
 console_unlock+0x13b/0x4d0 kernel/printk/printk.c:3118
 vprintk_emit+0x5a6/0x770 kernel/printk/printk.c:2348
 _printk+0xd5/0x120 kernel/printk/printk.c:2373
 __ext4_error+0x392/0x3b0 fs/ext4/super.c:822
 ext4_validate_block_bitmap+0xe78/0x1200 fs/ext4/balloc.c:440
 ext4_read_block_bitmap_nowait+0x61f/0xa80 fs/ext4/balloc.c:556
 ext4_mb_prefetch+0x248/0x390 fs/ext4/mballoc.c:2749
 ext4_run_li_request fs/ext4/super.c:3681 [inline]
 ext4_lazyinit_thread+0x540/0x1930 fs/ext4/super.c:3803
 kthread+0x2f2/0x390 kernel/kthread.c:389
 ret_from_fork+0x4d/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>
rcu: rcu_preempt kthread starved for 10463 jiffies! g68089 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->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:R  running task     stack:24688 pid:17    tgid:17    ppid:2      flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5188 [inline]
 __schedule+0x1800/0x4a60 kernel/sched/core.c:6529
 __schedule_loop kernel/sched/core.c:6606 [inline]
 schedule+0x14b/0x320 kernel/sched/core.c:6621
 schedule_timeout+0x1be/0x310 kernel/time/timer.c:2581
 rcu_gp_fqs_loop+0x2df/0x1330 kernel/rcu/tree.c:2034
 rcu_gp_kthread+0xa7/0x3b0 kernel/rcu/tree.c:2236
 kthread+0x2f2/0x390 kernel/kthread.c:389
 ret_from_fork+0x4d/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
CPU: 0 UID: 0 PID: 7395 Comm: kworker/u8:11 Not tainted 6.10.0-syzkaller-12030-g66ebbdfdeb09 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/27/2024
Workqueue: events_unbound toggle_allocation_gate
RIP: 0010:csd_lock_wait kernel/smp.c:312 [inline]
RIP: 0010:smp_call_function_many_cond+0x1860/0x29d0 kernel/smp.c:856
Code: 45 8b 65 00 44 89 e6 83 e6 01 31 ff e8 89 14 0c 00 41 83 e4 01 49 bc 00 00 00 00 00 fc ff df 75 07 e8 34 10 0c 00 eb 38 f3 90 <42> 0f b6 04 23 84 c0 75 11 41 f7 45 00 01 00 00 00 74 1e e8 18 10
RSP: 0018:ffffc90008e67700 EFLAGS: 00000293
RAX: ffffffff81877368 RBX: 1ffff110172a88f9 RCX: ffff88801a353c00
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc90008e678e0 R08: ffffffff81877337 R09: 1ffffffff2600500
R10: dffffc0000000000 R11: fffffbfff2600501 R12: dffffc0000000000
R13: ffff8880b95447c8 R14: ffff8880b943fb80 R15: 0000000000000001
FS:  0000000000000000(0000) GS:ffff8880b9400000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055926f010548 CR3: 000000000e134000 CR4: 0000000000350ef0
Call Trace:
 <IRQ>
 </IRQ>
 <TASK>
 on_each_cpu_cond_mask+0x3f/0x80 kernel/smp.c:1023
 on_each_cpu include/linux/smp.h:71 [inline]
 text_poke_sync arch/x86/kernel/alternative.c:2085 [inline]
 text_poke_bp_batch+0x352/0xb30 arch/x86/kernel/alternative.c:2295
 text_poke_flush arch/x86/kernel/alternative.c:2486 [inline]
 text_poke_finish+0x30/0x50 arch/x86/kernel/alternative.c:2493
 arch_jump_label_transform_apply+0x1c/0x30 arch/x86/kernel/jump_label.c:146
 static_key_enable_cpuslocked+0x136/0x260 kernel/jump_label.c:210
 static_key_enable+0x1a/0x20 kernel/jump_label.c:223
 toggle_allocation_gate+0xb5/0x250 mm/kfence/core.c:833
 process_one_work kernel/workqueue.c:3231 [inline]
 process_scheduled_works+0xa2e/0x1830 kernel/workqueue.c:3312
 worker_thread+0x86d/0xd40 kernel/workqueue.c:3390
 kthread+0x2f2/0x390 kernel/kthread.c:389
 ret_from_fork+0x4d/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/07/23 09:38 upstream 66ebbdfdeb09 708c10c4 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root INFO: rcu detected stall in ext4_lazyinit_thread
* Struck through repros no longer work on HEAD.