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INFO: rcu detected stall in sys_getdents64 (2)

Status: upstream: reported on 2025/02/05 16:20
Reported-by: syzbot+37d7c102454fc0bf2a62@syzkaller.appspotmail.com
First crash: 5h31m, last: 5h31m
▶ ▼ Similar bugs (3)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: rcu detected stall in sys_getdents64 net C error 18 18d 118d 0/28 upstream: reported C repro on 2024/10/10 03:27
linux-5.15 INFO: rcu detected stall in sys_getdents64 2 186d 255d 0/3 auto-obsoleted due to no activity on 2024/11/10 23:35
android-5-15 BUG: soft lockup in sys_getdents64 6 281d 294d 0/2 auto-obsoleted due to no activity on 2024/07/28 23:49

Sample crash report:
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	0-...!: (0 ticks this GP) idle=dc1/1/0x4000000000000000 softirq=24921/24921 fqs=0 
	(detected by 1, t=10502 jiffies, g=29925, q=71)
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 3546 Comm: udevd Not tainted 5.15.178-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024
RIP: 0010:memory_is_nonzero mm/kasan/generic.c:101 [inline]
RIP: 0010:memory_is_poisoned_n mm/kasan/generic.c:128 [inline]
RIP: 0010:memory_is_poisoned mm/kasan/generic.c:159 [inline]
RIP: 0010:check_region_inline mm/kasan/generic.c:180 [inline]
RIP: 0010:kasan_check_range+0x62/0x290 mm/kasan/generic.c:189
Code: b8 00 00 00 00 00 fc ff df 4e 8d 0c 03 4c 8d 54 37 ff 49 c1 ea 03 49 bb 01 00 00 00 00 fc ff df 4f 8d 34 1a 4c 89 f5 4c 29 cd <48> 83 fd 10 7f 26 48 85 ed 0f 84 3a 01 00 00 49 f7 d2 49 01 da 41
RSP: 0018:ffffc90000007d38 EFLAGS: 00000002
RAX: 0000000000000001 RBX: 1ffffffff1c150ed RCX: ffffffff816f8a46
RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff8e0a8768
RBP: 0000000000000001 R08: dffffc0000000000 R09: fffffbfff1c150ed
R10: 1ffffffff1c150ed R11: dffffc0000000001 R12: ffff8880b8e2a200
R13: 0000000000000001 R14: fffffbfff1c150ee R15: ffff88807e7c6418
FS:  00007f0c63592c80(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f2f350a1f98 CR3: 000000007db17000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <NMI>
 </NMI>
 <IRQ>
 instrument_atomic_read include/linux/instrumented.h:71 [inline]
 test_bit include/asm-generic/bitops/instrumented-non-atomic.h:134 [inline]
 cpumask_test_cpu include/linux/cpumask.h:344 [inline]
 cpu_online include/linux/cpumask.h:895 [inline]
 trace_hrtimer_expire_exit include/trace/events/timer.h:283 [inline]
 __run_hrtimer kernel/time/hrtimer.c:1691 [inline]
 __hrtimer_run_queues+0x5f6/0xcf0 kernel/time/hrtimer.c:1752
 hrtimer_interrupt+0x392/0x980 kernel/time/hrtimer.c:1814
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1097 [inline]
 __sysvec_apic_timer_interrupt+0x13b/0x4b0 arch/x86/kernel/apic/apic.c:1114
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1108 [inline]
 sysvec_apic_timer_interrupt+0x9b/0xc0 arch/x86/kernel/apic/apic.c:1108
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676
RIP: 0010:lock_is_held_type+0x137/0x180
Code: 75 40 48 c7 04 24 00 00 00 00 9c 8f 04 24 f7 04 24 00 02 00 00 75 46 41 f7 c4 00 02 00 00 74 01 fb 65 48 8b 04 25 28 00 00 00 <48> 3b 44 24 08 75 3c 89 e8 48 83 c4 10 5b 41 5c 41 5d 41 5e 41 5f
RSP: 0018:ffffc90002d3fc70 EFLAGS: 00000206
RAX: 6acdc1fd1917d400 RBX: 0000000000000002 RCX: ffff88807e7c5940
RDX: ffff88807e7c5940 RSI: ffffffff8aab3e20 RDI: ffffffff8af9f2c0
RBP: 0000000000000001 R08: ffffffff81fd1f77 R09: ffffed1003e820af
R10: 0000000000000000 R11: dffffc0000000001 R12: 0000000000000246
R13: ffff88807e7c5940 R14: 00000000ffffffff R15: ffffffff8cc526b0
 lock_is_held include/linux/lockdep.h:287 [inline]
 kernfs_active fs/kernfs/dir.c:37 [inline]
 kernfs_dir_pos+0x27c/0x420 fs/kernfs/dir.c:1690
 kernfs_dir_next_pos fs/kernfs/dir.c:1703 [inline]
 kernfs_fop_readdir+0x577/0x7e0 fs/kernfs/dir.c:1732
 iterate_dir+0x224/0x570
 __do_sys_getdents64 fs/readdir.c:369 [inline]
 __se_sys_getdents64+0x209/0x4f0 fs/readdir.c:354
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f0c636a0910
Code: 87 43 04 ff c8 7e 08 48 89 ef e8 4d 0e fc ff 4c 89 e0 5b 5d 41 5c c3 b8 ff ff ff 7f 48 39 c2 48 0f 47 d0 b8 d9 00 00 00 0f 05 <48> 3d 00 f0 ff ff 76 10 48 8b 15 e9 74 0f 00 f7 d8 64 89 02 48 83
RSP: 002b:00007fff350b0688 EFLAGS: 00000293 ORIG_RAX: 00000000000000d9
RAX: ffffffffffffffda RBX: 0000559e3d45fa80 RCX: 00007f0c636a0910
RDX: 0000000000008000 RSI: 0000559e3d45fab0 RDI: 000000000000000e
RBP: 0000559e3d45fa84 R08: 0000559e3d45fa80 R09: 0000000000000020
R10: 0000000000000812 R11: 0000000000000293 R12: 0000559e3d3ea680
R13: fffffffffffffe60 R14: 0000000000000002 R15: 0000559e3d45fab0
 </TASK>
rcu: rcu_preempt kthread timer wakeup didn't happen for 10501 jiffies! g29925 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402
rcu: 	Possible timer handling issue on cpu=0 timer-softirq=9655
rcu: rcu_preempt kthread starved for 10502 jiffies! g29925 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:26712 pid:   15 ppid:     2 flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5027 [inline]
 __schedule+0x12c4/0x45b0 kernel/sched/core.c:6373
 schedule+0x11b/0x1f0 kernel/sched/core.c:6456
 schedule_timeout+0x1b9/0x300 kernel/time/timer.c:1914
 rcu_gp_fqs_loop+0x2bf/0x1080 kernel/rcu/tree.c:1972
 rcu_gp_kthread+0xa4/0x360 kernel/rcu/tree.c:2145
 kthread+0x3f6/0x4f0 kernel/kthread.c:334
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
 </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: 3546 Comm: udevd Not tainted 5.15.178-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024
RIP: 0010:__lock_acquire+0xf33/0x1ff0
Code: 29 d0 89 d6 c1 c6 08 31 c6 01 ca 29 f1 89 f3 c1 c3 10 31 cb 01 d6 29 da 89 dd c1 c5 13 31 d5 01 f3 29 ee 01 eb c1 c5 04 31 f5 <48> c1 e5 20 48 c7 c0 18 bb 0a 8e 48 c1 e8 03 0f b6 04 38 84 c0 0f
RSP: 0018:ffffc90000007a60 EFLAGS: 00000082
RAX: 0000000000104595 RBX: 0000000050ef4013 RCX: 000000001055937d
RDX: 00000000c3affd79 RSI: 00000000ca838a38 RDI: dffffc0000000000
RBP: 000000009be2421a R08: dffffc0000000000 R09: fffffbfff2131821
R10: 0000000000000000 R11: dffffc0000000001 R12: 0000000000000003
R13: ffff88807e7c6428 R14: 1ffff1100fcf8c84 R15: 0000000000004016
FS:  00007f0c63592c80(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f2f350a1f98 CR3: 000000007db17000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <NMI>
 </NMI>
 <IRQ>
 lock_acquire+0x1db/0x4f0 kernel/locking/lockdep.c:5623
 rcu_lock_acquire+0x2a/0x30 include/linux/rcupdate.h:312
 rcu_read_lock include/linux/rcupdate.h:739 [inline]
 advance_sched+0x6ce/0x940 net/sched/sch_taprio.c:769
 __run_hrtimer kernel/time/hrtimer.c:1688 [inline]
 __hrtimer_run_queues+0x598/0xcf0 kernel/time/hrtimer.c:1752
 hrtimer_interrupt+0x392/0x980 kernel/time/hrtimer.c:1814
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1097 [inline]
 __sysvec_apic_timer_interrupt+0x13b/0x4b0 arch/x86/kernel/apic/apic.c:1114
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1108 [inline]
 sysvec_apic_timer_interrupt+0x9b/0xc0 arch/x86/kernel/apic/apic.c:1108
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676
RIP: 0010:lock_is_held_type+0x137/0x180
Code: 75 40 48 c7 04 24 00 00 00 00 9c 8f 04 24 f7 04 24 00 02 00 00 75 46 41 f7 c4 00 02 00 00 74 01 fb 65 48 8b 04 25 28 00 00 00 <48> 3b 44 24 08 75 3c 89 e8 48 83 c4 10 5b 41 5c 41 5d 41 5e 41 5f
RSP: 0018:ffffc90002d3fc70 EFLAGS: 00000206
RAX: 6acdc1fd1917d400 RBX: 0000000000000002 RCX: ffff88807e7c5940
RDX: ffff88807e7c5940 RSI: ffffffff8aab3e20 RDI: ffffffff8af9f2c0
RBP: 0000000000000001 R08: ffffffff81fd1f77 R09: ffffed1003e820af
R10: 0000000000000000 R11: dffffc0000000001 R12: 0000000000000246
R13: ffff88807e7c5940 R14: 00000000ffffffff R15: ffffffff8cc526b0
 lock_is_held include/linux/lockdep.h:287 [inline]
 kernfs_active fs/kernfs/dir.c:37 [inline]
 kernfs_dir_pos+0x27c/0x420 fs/kernfs/dir.c:1690
 kernfs_dir_next_pos fs/kernfs/dir.c:1703 [inline]
 kernfs_fop_readdir+0x577/0x7e0 fs/kernfs/dir.c:1732
 iterate_dir+0x224/0x570
 __do_sys_getdents64 fs/readdir.c:369 [inline]
 __se_sys_getdents64+0x209/0x4f0 fs/readdir.c:354
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f0c636a0910
Code: 87 43 04 ff c8 7e 08 48 89 ef e8 4d 0e fc ff 4c 89 e0 5b 5d 41 5c c3 b8 ff ff ff 7f 48 39 c2 48 0f 47 d0 b8 d9 00 00 00 0f 05 <48> 3d 00 f0 ff ff 76 10 48 8b 15 e9 74 0f 00 f7 d8 64 89 02 48 83
RSP: 002b:00007fff350b0688 EFLAGS: 00000293 ORIG_RAX: 00000000000000d9
RAX: ffffffffffffffda RBX: 0000559e3d45fa80 RCX: 00007f0c636a0910
RDX: 0000000000008000 RSI: 0000559e3d45fab0 RDI: 000000000000000e
RBP: 0000559e3d45fa84 R08: 0000559e3d45fa80 R09: 0000000000000020
R10: 0000000000000812 R11: 0000000000000293 R12: 0000559e3d3ea680
R13: fffffffffffffe60 R14: 0000000000000002 R15: 0000559e3d45fab0
 </TASK>

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/02/05 16:19 linux-5.15.y c16c81c81336 4dc70884 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in sys_getdents64
* Struck through repros no longer work on HEAD.