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INFO: rcu detected stall in do_faccessat (6)

Status: auto-obsoleted due to no activity on 2024/02/29 22:48
Subsystems: kernel
[Documentation on labels]
First crash: 123d, last: 123d
▶ ▼ Similar bugs (5)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: rcu detected stall in do_faccessat (4) fs 1 1009d 1009d 0/26 auto-closed as invalid on 2021/09/26 22:47
upstream INFO: rcu detected stall in do_faccessat (2) fs 1 1325d 1325d 0/26 auto-closed as invalid on 2020/12/14 19:23
upstream INFO: rcu detected stall in do_faccessat (3) fs 1 1228d 1228d 0/26 auto-closed as invalid on 2021/03/21 19:47
upstream INFO: rcu detected stall in do_faccessat (5) fs 2 906d 926d 0/26 auto-closed as invalid on 2022/02/07 01:08
upstream INFO: rcu detected stall in do_faccessat fs 1 1423d 1423d 0/26 auto-closed as invalid on 2020/09/07 18:08

Sample crash report:
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	0-...!: (0 ticks this GP) idle=eafc/1/0x4000000000000000 softirq=83000/83000 fqs=2
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P5099/1:b..l
rcu: 	(detected by 1, t=10502 jiffies, g=140717, q=119 ncpus=2)
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 1384 Comm: udevd Not tainted 6.7.0-rc6-next-20231222-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/17/2023
RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline]
RIP: 0010:_raw_spin_unlock_irqrestore+0x31/0x70 kernel/locking/spinlock.c:194
Code: f5 53 48 8b 74 24 10 48 89 fb 48 83 c7 18 e8 26 4b d8 f6 48 89 df e8 ee c2 d8 f6 f7 c5 00 02 00 00 75 1f 9c 58 f6 c4 02 75 2f <bf> 01 00 00 00 e8 35 6c ca f6 65 8b 05 56 a7 73 75 85 c0 74 12 5b
RSP: 0018:ffffc90000007cd8 EFLAGS: 00000046
RAX: 0000000000000046 RBX: ffffffff92c239c0 RCX: ffffffff8168de93
RDX: dffffc0000000000 RSI: 0000000000000004 RDI: ffffffff92c239c0
RBP: 0000000000000002 R08: 0000000000000000 R09: fffffbfff2584738
R10: ffffffff92c239c3 R11: ffffffff8acf3060 R12: 0000000000000002
R13: ffff88802aad6340 R14: 1ffff92000000fa2 R15: ffffffff92c239b8
FS:  00007f5623a9cc80(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000020000440 CR3: 000000001e2d0000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <NMI>
 </NMI>
 <IRQ>
 debug_object_activate+0x349/0x540 lib/debugobjects.c:726
 debug_hrtimer_activate kernel/time/hrtimer.c:422 [inline]
 debug_activate kernel/time/hrtimer.c:477 [inline]
 enqueue_hrtimer+0x25/0x320 kernel/time/hrtimer.c:1087
 __run_hrtimer kernel/time/hrtimer.c:1705 [inline]
 __hrtimer_run_queues+0xa0f/0xc20 kernel/time/hrtimer.c:1752
 hrtimer_interrupt+0x31b/0x800 kernel/time/hrtimer.c:1814
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1065 [inline]
 __sysvec_apic_timer_interrupt+0x10c/0x410 arch/x86/kernel/apic/apic.c:1082
 sysvec_apic_timer_interrupt+0x90/0xb0 arch/x86/kernel/apic/apic.c:1076
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:649
RIP: 0010:preempt_count arch/x86/include/asm/preempt.h:26 [inline]
RIP: 0010:check_kcov_mode kernel/kcov.c:173 [inline]
RIP: 0010:write_comp_data+0x11/0x80 kernel/kcov.c:236
Code: 8b 05 e3 b4 7b 7e 48 8b 80 f0 15 00 00 c3 66 66 2e 0f 1f 84 00 00 00 00 00 49 89 d2 49 89 f8 49 89 f1 65 48 8b 15 bf b4 7b 7e <65> 8b 05 c0 b4 7b 7e a9 00 01 ff 00 74 0f f6 c4 01 74 59 8b 82 fc
RSP: 0018:ffffc90003fbf990 EFLAGS: 00000293
RAX: 0000000000000000 RBX: 00007f5623716da6 RCX: ffffffff810080e5
RDX: ffff888026cd0000 RSI: 0000000000000002 RDI: 0000000000000005
RBP: 0000000000000001 R08: 0000000000000005 R09: 0000000000000002
R10: 0000000000000001 R11: 0000000000000000 R12: 0000000000000000
R13: ffffffff817562b0 R14: ffffc90003fbfac8 R15: ffff888026cd0000
 in_gate_area_no_mm+0x25/0x60 arch/x86/entry/vsyscall/vsyscall_64.c:345
 is_kernel_text include/linux/kallsyms.h:31 [inline]
 core_kernel_text kernel/extable.c:68 [inline]
 kernel_text_address+0x31/0xf0 kernel/extable.c:99
 __kernel_text_address+0xd/0x30 kernel/extable.c:79
 unwind_get_return_address+0x78/0xe0 arch/x86/kernel/unwind_orc.c:369
 arch_stack_walk+0xbe/0x170 arch/x86/kernel/stacktrace.c:26
 stack_trace_save+0x95/0xd0 kernel/stacktrace.c:122
 kasan_save_stack+0x33/0x50 mm/kasan/common.c:47
 kasan_set_track+0x24/0x30 mm/kasan/common.c:61
 unpoison_slab_object mm/kasan/common.c:282 [inline]
 __kasan_slab_alloc+0x81/0x90 mm/kasan/common.c:308
 kasan_slab_alloc include/linux/kasan.h:200 [inline]
 slab_post_alloc_hook mm/slub.c:3817 [inline]
 slab_alloc_node mm/slub.c:3864 [inline]
 kmem_cache_alloc+0x136/0x320 mm/slub.c:3871
 getname_flags.part.0+0x50/0x4e0 fs/namei.c:140
 getname_flags+0x9b/0xf0 include/linux/audit.h:322
 user_path_at_empty+0x2c/0x60 fs/namei.c:2919
 user_path_at include/linux/namei.h:57 [inline]
 do_faccessat+0x13c/0xae0 fs/open.c:488
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0x40/0x110 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x62/0x6a
RIP: 0033:0x7f5623716da6
Code: 89 e0 5b 5d 41 5c 41 5d 41 5e 41 5f c3 41 55 41 89 ca 41 89 d5 b8 b7 01 00 00 41 54 41 89 cc 55 53 48 81 ec 98 00 00 00 0f 05 <48> 89 c2 48 3d 00 f0 ff ff 76 10 48 8b 05 50 a0 0d 00 f7 da 64 89
RSP: 002b:00007ffe5a0273c0 EFLAGS: 00000206 ORIG_RAX: 00000000000001b7
RAX: ffffffffffffffda RBX: 00007ffe5a028550 RCX: 00007f5623716da6
RDX: 0000000000000000 RSI: 00007f5623b8a9d0 RDI: 000000000000000b
RBP: 0000561977897c60 R08: 0000561977867140 R09: 00007f56237f1b20
R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
 </TASK>
task:syz-executor.1  state:R  running task     stack:24224 pid:5099  tgid:5099  ppid:5084   flags:0x00000002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5400 [inline]
 __schedule+0xf15/0x5c80 kernel/sched/core.c:6727
 preempt_schedule_common+0x44/0xc0 kernel/sched/core.c:6904
 preempt_schedule_thunk+0x1a/0x30 arch/x86/entry/thunk_64.S:45
 unwind_next_frame+0x1c7a/0x2390 arch/x86/kernel/unwind_orc.c:672
 __unwind_start+0x5a2/0x880 arch/x86/kernel/unwind_orc.c:760
 unwind_start arch/x86/include/asm/unwind.h:64 [inline]
 arch_stack_walk+0xaf/0x170 arch/x86/kernel/stacktrace.c:24
 stack_trace_save+0x95/0xd0 kernel/stacktrace.c:122
 save_stack+0x15e/0x1f0 mm/page_owner.c:130
 __reset_page_owner+0x51/0x2e0 mm/page_owner.c:151
 reset_page_owner include/linux/page_owner.h:24 [inline]
 free_pages_prepare mm/page_alloc.c:1140 [inline]
 free_unref_page_prepare+0x51f/0xb10 mm/page_alloc.c:2383
 free_unref_page+0x33/0x3c0 mm/page_alloc.c:2523
 vfree+0x181/0x7a0 mm/vmalloc.c:2842
 copy_entries_to_user net/ipv6/netfilter/ip6_tables.c:882 [inline]
 get_entries net/ipv6/netfilter/ip6_tables.c:1039 [inline]
 do_ip6t_get_ctl+0x8e8/0xae0 net/ipv6/netfilter/ip6_tables.c:1669
 nf_getsockopt+0x76/0xe0 net/netfilter/nf_sockopt.c:116
 ipv6_getsockopt+0x1f9/0x2b0 net/ipv6/ipv6_sockglue.c:1488
 tcp_getsockopt+0x97/0xf0 net/ipv4/tcp.c:4361
 do_sock_getsockopt+0x2e1/0x6c0 net/socket.c:2371
 __sys_getsockopt+0x1a1/0x270 net/socket.c:2400
 __do_sys_getsockopt net/socket.c:2410 [inline]
 __se_sys_getsockopt net/socket.c:2407 [inline]
 __x64_sys_getsockopt+0xbd/0x150 net/socket.c:2407
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0x40/0x110 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x62/0x6a
RIP: 0033:0x7f98a267e88a
RSP: 002b:00007ffff24ba4e8 EFLAGS: 00000212 ORIG_RAX: 0000000000000037
RAX: ffffffffffffffda RBX: 00007ffff24ba570 RCX: 00007f98a267e88a
RDX: 0000000000000041 RSI: 0000000000000029 RDI: 0000000000000003
RBP: 0000000000000003 R08: 00007ffff24ba50c R09: 0079746972756365
R10: 00007ffff24ba570 R11: 0000000000000212 R12: 00007f98a277a640
R13: 00007ffff24ba50c R14: 0000000000000000 R15: 00007f98a277ad00
 </TASK>
rcu: rcu_preempt kthread starved for 10498 jiffies! g140717 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=1
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:28256 pid:17    tgid:17    ppid:2      flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5400 [inline]
 __schedule+0xf15/0x5c80 kernel/sched/core.c:6727
 __schedule_loop kernel/sched/core.c:6802 [inline]
 schedule+0xe7/0x270 kernel/sched/core.c:6817
 schedule_timeout+0x136/0x290 kernel/time/timer.c:2183
 rcu_gp_fqs_loop+0x1eb/0xb00 kernel/rcu/tree.c:1631
 rcu_gp_kthread+0x271/0x380 kernel/rcu/tree.c:1830
 kthread+0x2c1/0x3a0 kernel/kthread.c:388
 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:242
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
CPU: 1 PID: 2780 Comm: kworker/u4:8 Not tainted 6.7.0-rc6-next-20231222-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/17/2023
Workqueue: events_unbound toggle_allocation_gate
RIP: 0010:csd_lock_wait kernel/smp.c:311 [inline]
RIP: 0010:smp_call_function_many_cond+0x4e4/0x1570 kernel/smp.c:855
Code: 0b 00 85 ed 74 4d 48 b8 00 00 00 00 00 fc ff df 4d 89 f4 4c 89 f5 49 c1 ec 03 83 e5 07 49 01 c4 83 c5 03 e8 7e c5 0b 00 f3 90 <41> 0f b6 04 24 40 38 c5 7c 08 84 c0 0f 85 44 0e 00 00 8b 43 08 31
RSP: 0018:ffffc9000af47920 EFLAGS: 00000293
RAX: 0000000000000000 RBX: ffff8880b9844840 RCX: ffffffff817c4e68
RDX: ffff888028cd8000 RSI: ffffffff817c4e42 RDI: 0000000000000005
RBP: 0000000000000003 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000000 R12: ffffed1017308909
R13: 0000000000000001 R14: ffff8880b9844848 R15: ffff8880b993dec0
FS:  0000000000000000(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000555557122918 CR3: 000000000cf78000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 </IRQ>
 <TASK>
 on_each_cpu_cond_mask+0x40/0x90 kernel/smp.c:1023
 on_each_cpu include/linux/smp.h:71 [inline]
 text_poke_sync arch/x86/kernel/alternative.c:2086 [inline]
 text_poke_bp_batch+0x22b/0x750 arch/x86/kernel/alternative.c:2296
 text_poke_flush arch/x86/kernel/alternative.c:2487 [inline]
 text_poke_flush arch/x86/kernel/alternative.c:2484 [inline]
 text_poke_finish+0x30/0x40 arch/x86/kernel/alternative.c:2494
 arch_jump_label_transform_apply+0x1c/0x30 arch/x86/kernel/jump_label.c:146
 jump_label_update+0x1d7/0x400 kernel/jump_label.c:829
 static_key_enable_cpuslocked+0x1b7/0x270 kernel/jump_label.c:205
 static_key_enable+0x1a/0x20 kernel/jump_label.c:218
 toggle_allocation_gate mm/kfence/core.c:826 [inline]
 toggle_allocation_gate+0xf4/0x250 mm/kfence/core.c:818
 process_one_work+0x8a4/0x15f0 kernel/workqueue.c:2633
 process_scheduled_works kernel/workqueue.c:2706 [inline]
 worker_thread+0x8b6/0x1290 kernel/workqueue.c:2787
 kthread+0x2c1/0x3a0 kernel/kthread.c:388
 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:242
 </TASK>

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2023/12/31 22:37 linux-next 39676dfe5233 fb427a07 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root INFO: rcu detected stall in do_faccessat
* Struck through repros no longer work on HEAD.