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INFO: rcu detected stall in sock_alloc_file

Status: closed as invalid on 2024/02/01 10:31
Subsystems: fs
[Documentation on labels]
First crash: 810d, last: 810d
▶ ▼ Similar bugs (6)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-6.6 INFO: rcu detected stall in sock_alloc_file (2) 1 1 68d 68d 0/2 upstream: reported on 2025/12/05 04:14
linux-6.6 INFO: rcu detected stall in sock_alloc_file 1 1 170d 170d 0/2 auto-obsoleted due to no activity on 2025/12/03 21:35
linux-5.15 INFO: rcu detected stall in sock_alloc_file 1 1 221d 221d 0/3 auto-obsoleted due to no activity on 2025/10/13 16:41
upstream INFO: rcu detected stall in sock_alloc_file (2) mm 1 6 389d 441d 0/29 auto-obsoleted due to no activity on 2025/04/19 00:40
linux-5.15 INFO: rcu detected stall in sock_alloc_file (2) 1 3 50d 110d 0/3 upstream: reported on 2025/10/24 19:33
linux-6.1 INFO: rcu detected stall in sock_alloc_file 1 1 161d 161d 0/3 auto-obsoleted due to no activity on 2025/12/12 11:49

Sample crash report:
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	0-...!: (1 GPs behind) idle=4b74/1/0x4000000000000000 softirq=109799/109802 fqs=1
rcu: 	(detected by 1, t=10502 jiffies, g=167225, q=141 ncpus=2)
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 16474 Comm: syz-executor.0 Not tainted 6.7.0-rc2-syzkaller-00147-gf1a09972a45a #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/10/2023
RIP: 0010:bytes_is_nonzero mm/kasan/generic.c:85 [inline]
RIP: 0010:memory_is_nonzero mm/kasan/generic.c:102 [inline]
RIP: 0010:memory_is_poisoned_n mm/kasan/generic.c:127 [inline]
RIP: 0010:memory_is_poisoned mm/kasan/generic.c:159 [inline]
RIP: 0010:check_region_inline mm/kasan/generic.c:178 [inline]
RIP: 0010:kasan_check_range+0x10a/0x190 mm/kasan/generic.c:187
Code: b8 01 00 00 00 7c 0b 44 89 c2 e8 71 ed ff ff 83 f0 01 5b 5d 41 5c c3 48 85 d2 74 4f 48 01 ea eb 09 48 83 c0 01 48 39 d0 74 41 <80> 38 00 74 f2 eb b6 41 bc 08 00 00 00 45 29 dc 49 8d 14 2c eb 0c
RSP: 0018:ffffc90000007d00 EFLAGS: 00000082
RAX: ffffed100d16a190 RBX: ffffed100d16a191 RCX: ffffffff88a1fd0d
RDX: ffffed100d16a191 RSI: 0000000000000004 RDI: ffff888068b50c80
RBP: ffffed100d16a190 R08: 0000000000000001 R09: ffffed100d16a190
R10: ffff888068b50c83 R11: 0000000000000000 R12: 0000000000000000
R13: ffff888068b50c00 R14: 0000000000000000 R15: dffffc0000000000
FS:  00007fe3e694d6c0(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fd092c37183 CR3: 0000000031150000 CR4: 0000000000350ef0
Call Trace:
 <NMI>
 </NMI>
 <IRQ>
 instrument_atomic_write include/linux/instrumented.h:82 [inline]
 atomic_set include/linux/atomic/atomic-instrumented.h:67 [inline]
 taprio_set_budgets+0x19d/0x310 net/sched/sch_taprio.c:683
 advance_sched+0x5de/0xc60 net/sched/sch_taprio.c:988
 __run_hrtimer kernel/time/hrtimer.c:1688 [inline]
 __hrtimer_run_queues+0x203/0xc20 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+0x105/0x400 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:645
RIP: 0010:__kasan_slab_alloc+0x4/0x90 mm/kasan/common.c:300
Code: e9 21 2b 00 00 48 8d 42 ff e9 54 ff ff ff ba 02 00 00 00 e9 76 ff ff ff 66 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 00 66 0f 1f 00 <41> 55 41 89 d5 81 e2 00 04 00 00 41 54 49 89 fc 55 89 cd 53 48 89
RSP: 0018:ffffc90004a57c88 EFLAGS: 00000206
RAX: 0000000000000001 RBX: 0000000000000dc0 RCX: 0000000000000001
RDX: 0000000000000dc0 RSI: ffff8880784c2a00 RDI: ffff888015252b40
RBP: ffffc90004a57cd8 R08: 0000000000000001 R09: 0000000000000001
R10: ffffffff8f194857 R11: 0000000000000000 R12: 00000000000001d0
R13: ffff888015252b40 R14: 0000000000000dc0 R15: 0000000000000001
 kasan_slab_alloc include/linux/kasan.h:188 [inline]
 slab_post_alloc_hook mm/slab.h:763 [inline]
 slab_alloc_node mm/slub.c:3478 [inline]
 slab_alloc mm/slub.c:3486 [inline]
 __kmem_cache_alloc_lru mm/slub.c:3493 [inline]
 kmem_cache_alloc+0x15d/0x2f0 mm/slub.c:3502
 kmem_cache_zalloc include/linux/slab.h:711 [inline]
 alloc_empty_file+0x73/0x1d0 fs/file_table.c:216
 alloc_file+0x5e/0x7f0 fs/file_table.c:303
 alloc_file_pseudo+0x174/0x240 fs/file_table.c:346
 sock_alloc_file+0x50/0x1d0 net/socket.c:469
 __sys_socketpair+0x319/0x5a0 net/socket.c:1791
 __do_sys_socketpair net/socket.c:1820 [inline]
 __se_sys_socketpair net/socket.c:1817 [inline]
 __x64_sys_socketpair+0x96/0x100 net/socket.c:1817
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x40/0x110 arch/x86/entry/common.c:82
 entry_SYSCALL_64_after_hwframe+0x63/0x6b
RIP: 0033:0x7fe3e5c7cae9
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 20 00 00 90 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 b0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fe3e694d0c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000035
RAX: ffffffffffffffda RBX: 00007fe3e5d9c050 RCX: 00007fe3e5c7cae9
RDX: 0000000000000000 RSI: 0000000000000002 RDI: 0000000000000001
RBP: 00007fe3e5cc847a R08: 0000000000000000 R09: 0000000000000000
R10: 0000000020000200 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000006e R14: 00007fe3e5d9c050 R15: 00007fffa1ac2588
 </TASK>
rcu: rcu_preempt kthread starved for 10500 jiffies! g167225 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:27904 pid:17    tgid:17    ppid:2      flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5376 [inline]
 __schedule+0xedb/0x5af0 kernel/sched/core.c:6688
 __schedule_loop kernel/sched/core.c:6763 [inline]
 schedule+0xe9/0x270 kernel/sched/core.c:6778
 schedule_timeout+0x137/0x290 kernel/time/timer.c:2167
 rcu_gp_fqs_loop+0x1ec/0xb10 kernel/rcu/tree.c:1631
 rcu_gp_kthread+0x24b/0x380 kernel/rcu/tree.c:1830
 kthread+0x2c6/0x3a0 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: 12769 Comm: kworker/u4:8 Not tainted 6.7.0-rc2-syzkaller-00147-gf1a09972a45a #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/10/2023
Workqueue: events_unbound toggle_allocation_gate
RIP: 0010:csd_lock_wait kernel/smp.c:311 [inline]
RIP: 0010:smp_call_function_many_cond+0x4e9/0x1550 kernel/smp.c:855
Code: 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 b8 0b 00 f3 90 41 0f b6 04 24 <40> 38 c5 7c 08 84 c0 0f 85 24 0e 00 00 8b 43 08 31 ff 83 e0 01 41
RSP: 0018:ffffc9001197f930 EFLAGS: 00000293
RAX: 0000000000000000 RBX: ffff8880b98442c0 RCX: ffffffff817bd1d8
RDX: ffff8880798abb80 RSI: ffffffff817bd1b2 RDI: 0000000000000005
RBP: 0000000000000003 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000006 R12: ffffed1017308859
R13: 0000000000000001 R14: ffff8880b98442c8 R15: ffff8880b993d8c0
FS:  0000000000000000(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b31927000 CR3: 000000000cd77000 CR4: 0000000000350ef0
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:2006 [inline]
 text_poke_bp_batch+0x655/0x750 arch/x86/kernel/alternative.c:2216
 text_poke_flush arch/x86/kernel/alternative.c:2407 [inline]
 text_poke_flush arch/x86/kernel/alternative.c:2404 [inline]
 text_poke_finish+0x30/0x40 arch/x86/kernel/alternative.c:2414
 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:830 [inline]
 toggle_allocation_gate+0xf4/0x250 mm/kfence/core.c:822
 process_one_work+0x886/0x15d0 kernel/workqueue.c:2630
 process_scheduled_works kernel/workqueue.c:2703 [inline]
 worker_thread+0x8b9/0x1290 kernel/workqueue.c:2784
 kthread+0x2c6/0x3a0 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
2023/11/24 19:50 upstream f1a09972a45a 5b429f39 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root INFO: rcu detected stall in sock_alloc_file
* Struck through repros no longer work on HEAD.