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INFO: rcu detected stall in sock_alloc_file (2)

Status: upstream: reported on 2025/10/24 19:33
Reported-by: syzbot+adbc0bd310742910f945@syzkaller.appspotmail.com
First crash: 52d, last: 15d
▶ ▼ 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 10d 10d 0/2 upstream: reported on 2025/12/05 04:14
linux-6.6 INFO: rcu detected stall in sock_alloc_file 1 1 112d 112d 0/2 auto-obsoleted due to no activity on 2025/12/03 21:35
upstream INFO: rcu detected stall in sock_alloc_file fs 1 1 752d 752d 0/29 closed as invalid on 2024/02/01 10:31
linux-5.15 INFO: rcu detected stall in sock_alloc_file 1 1 163d 163d 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 331d 383d 0/29 auto-obsoleted due to no activity on 2025/04/19 00:40
linux-6.1 INFO: rcu detected stall in sock_alloc_file 1 1 103d 103d 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=3f1/1/0x4000000000000002 softirq=8081/8082 fqs=2101 
	(detected by 1, t=10506 jiffies, g=8565, q=1975)
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 4986 Comm: syz.2.194 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
RIP: 0010:check_preemption_disabled+0x18/0x110 lib/smp_processor_id.c:14
Code: 00 cc 48 c7 c7 20 e5 59 8a 48 c7 c6 60 e5 59 8a eb 00 55 41 57 41 56 53 48 83 ec 10 65 48 8b 04 25 28 00 00 00 48 89 44 24 08 <65> 8b 05 49 97 58 76 65 8b 0d b2 f1 58 76 f7 c1 ff ff ff 7f 74 1f
RSP: 0018:ffffc90000007468 EFLAGS: 00000082
RAX: f4e657b633bc8d00 RBX: ffff888029afe578 RCX: ffff888029c33b80
RDX: 0000000000000100 RSI: ffffffff8a59e560 RDI: ffffffff8a59e520
RBP: ffffc900000075d0 R08: dffffc0000000000 R09: fffffbfff1ff7c19
R10: fffffbfff1ff7c19 R11: 1ffffffff1ff7c18 R12: 0000000000000001
R13: 1ffff92000000e9c R14: ffffc90000007560 R15: ffffc900000076c0
FS:  00007f50000d36c0(0000) GS:ffff8880b9000000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffb4f2c5d58 CR3: 000000007cac2000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
 <IRQ>
 rcu_dynticks_curr_cpu_in_eqs kernel/rcu/tree.c:331 [inline]
 rcu_is_watching+0x11/0xa0 kernel/rcu/tree.c:1123
 rcu_read_lock include/linux/rcupdate.h:741 [inline]
 __perf_event_output kernel/events/core.c:7800 [inline]
 perf_event_output_forward+0xb9/0x280 kernel/events/core.c:7822
 __perf_event_overflow+0x364/0x530 kernel/events/core.c:9515
 perf_tp_event+0x32c/0xb50 kernel/events/core.c:10047
 perf_trace_run_bpf_submit+0xf3/0x1c0 kernel/events/core.c:10021
 perf_trace_preemptirq_template+0x2be/0x380 include/trace/events/preemptirq.h:14
 trace_irq_enable_rcuidle+0x108/0x180 include/trace/events/preemptirq.h:40
 trace_hardirqs_on+0x57/0x80 kernel/trace/trace_preemptirq.c:44
 asm_sysvec_irq_work+0x16/0x20 arch/x86/include/asm/idtentry.h:713
RIP: 0010:rcu_read_unlock_special+0x84/0x480 kernel/rcu/tree_plugin.h:674
Code: f1 f1 f1 00 f2 f2 f2 4a 89 04 2b 66 42 c7 44 2b 09 f3 f3 42 c6 44 2b 0b f3 65 44 8b 35 ed 11 9e 7e 41 f7 c6 00 00 f0 00 74 45 <48> c7 44 24 20 0e 36 e0 45 4a c7 04 2b 00 00 00 00 66 42 c7 44 2b
RSP: 0018:ffffc90000007b00 EFLAGS: 00000206
RAX: f4e657b633bc8d00 RBX: 1ffff92000000f64 RCX: f4e657b633bc8d00
RDX: dffffc0000000000 RSI: ffffffff8a0b1c60 RDI: ffffffff8a59e580
RBP: ffffc90000007be0 R08: dffffc0000000000 R09: ffffed1017207662
R10: ffffed1017207662 R11: 1ffff11017207661 R12: ffffffff8c120c00
R13: dffffc0000000000 R14: 0000000000000246 R15: 0000000000000001
 __rcu_read_unlock+0x78/0xd0 kernel/rcu/tree_plugin.h:422
 rcu_read_unlock include/linux/rcupdate.h:772 [inline]
 ieee80211_rx_napi+0x1f4/0x360 net/mac80211/rx.c:5010
 ieee80211_rx include/net/mac80211.h:4573 [inline]
 ieee80211_handle_queued_frames+0x105/0x1b0 net/mac80211/main.c:237
 tasklet_action_common+0x298/0x400 kernel/softirq.c:806
 handle_softirqs+0x328/0x820 kernel/softirq.c:576
 __do_softirq kernel/softirq.c:610 [inline]
 invoke_softirq kernel/softirq.c:450 [inline]
 __irq_exit_rcu+0x12f/0x220 kernel/softirq.c:659
 irq_exit_rcu+0x5/0x20 kernel/softirq.c:671
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1108 [inline]
 sysvec_apic_timer_interrupt+0xa0/0xc0 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:orc_ip arch/x86/kernel/unwind_orc.c:30 [inline]
RIP: 0010:__orc_find arch/x86/kernel/unwind_orc.c:52 [inline]
RIP: 0010:orc_find arch/x86/kernel/unwind_orc.c:178 [inline]
RIP: 0010:unwind_next_frame+0x105e/0x1d90 arch/x86/kernel/unwind_orc.c:448
Code: c1 48 c1 f9 02 48 c1 e8 3f 48 01 c8 48 83 e0 fe 4d 8d 74 45 00 4c 89 f0 48 c1 e8 03 48 b9 00 00 00 00 00 fc ff df 0f b6 04 08 <84> c0 75 27 49 63 06 4c 01 f0 49 8d 4e 04 48 39 e8 4c 0f 46 e9 49
RSP: 0018:ffffc900034bf788 EFLAGS: 00000a03
RAX: 0000000000000000 RBX: ffffc900034bf848 RCX: dffffc0000000000
RDX: ffffffff8d7f98d4 RSI: ffffffff8def1c0e RDI: ffffffff8134794c
RBP: ffffffff81c6ec61 R08: 0000000000000001 R09: 0000000000000004
R10: fffff52000697f15 R11: 1ffff92000697f13 R12: ffffffff8d7f98d4
R13: ffffffff8d7f98d4 R14: ffffffff8d7f98d4 R15: ffffffff8d7f98d4
 arch_stack_walk+0x10c/0x140 arch/x86/kernel/stacktrace.c:25
 stack_trace_save+0x98/0xe0 kernel/stacktrace.c:122
 kasan_save_stack mm/kasan/common.c:38 [inline]
 kasan_set_track mm/kasan/common.c:46 [inline]
 set_alloc_info mm/kasan/common.c:434 [inline]
 __kasan_slab_alloc+0x9c/0xd0 mm/kasan/common.c:467
 kasan_slab_alloc include/linux/kasan.h:254 [inline]
 slab_post_alloc_hook+0x4c/0x380 mm/slab.h:519
 slab_alloc_node mm/slub.c:3225 [inline]
 slab_alloc mm/slub.c:3233 [inline]
 kmem_cache_alloc+0x100/0x290 mm/slub.c:3238
 kmem_cache_zalloc include/linux/slab.h:728 [inline]
 lsm_file_alloc security/security.c:574 [inline]
 security_file_alloc+0x30/0x110 security/security.c:1530
 __alloc_file+0xc2/0x240 fs/file_table.c:137
 alloc_empty_file+0x90/0x180 fs/file_table.c:181
 alloc_file+0x5b/0x4f0 fs/file_table.c:223
 alloc_file_pseudo+0x17a/0x1f0 fs/file_table.c:263
 sock_alloc_file+0xb3/0x240 net/socket.c:464
 __sys_socketpair+0x2cc/0x540 net/socket.c:1676
 __do_sys_socketpair net/socket.c:1705 [inline]
 __se_sys_socketpair net/socket.c:1702 [inline]
 __x64_sys_socketpair+0x97/0xb0 net/socket.c:1702
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f5001e6c749
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 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f50000d3038 EFLAGS: 00000246 ORIG_RAX: 0000000000000035
RAX: ffffffffffffffda RBX: 00007f50020c2fa0 RCX: 00007f5001e6c749
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000001
RBP: 00007f5001ef0f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000200000000580 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f50020c3038 R14: 00007f50020c2fa0 R15: 00007ffc42978fc8
 </TASK>

Crashes (2):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/11/30 01:31 linux-5.15.y cc5ec8769306 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf INFO: rcu detected stall in sock_alloc_file
2025/10/24 19:33 linux-5.15.y ac56c046adf4 c0460fcd .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf INFO: rcu detected stall in sock_alloc_file
* Struck through repros no longer work on HEAD.