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INFO: rcu detected stall in __sock_create (2)

Status: upstream: reported on 2025/08/14 08:18
Reported-by: syzbot+6301ec717de1cc8fd0f0@syzkaller.appspotmail.com
First crash: 209d, last: 1d10h
▶ ▼ Similar bugs (9)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-6.1 INFO: rcu detected stall in __sock_create (3) 1 10 23d 207d 0/3 upstream: reported on 2025/08/16 13:35
upstream INFO: rcu detected stall in __sock_create mm 1 1 2289d 2289d 0/29 closed as invalid on 2019/12/04 14:04
linux-6.6 INFO: rcu detected stall in __sock_create 1 9 23d 213d 0/2 upstream: reported on 2025/08/10 05:00
upstream INFO: rcu detected stall in __sock_create (3) mm 1 21 354d 588d 0/29 auto-obsoleted due to no activity on 2025/06/20 21:57
upstream INFO: rcu detected stall in __sock_create (2) mm 1 2 2254d 2254d 0/29 closed as invalid on 2020/01/08 05:33
linux-5.15 INFO: rcu detected stall in __sock_create 1 1 658d 658d 0/3 auto-obsoleted due to no activity on 2024/08/30 14:48
linux-6.1 INFO: rcu detected stall in __sock_create 1 3 526d 627d 0/3 auto-obsoleted due to no activity on 2025/01/09 18:19
linux-6.1 INFO: rcu detected stall in __sock_create (2) 1 2 362d 395d 0/3 auto-obsoleted due to no activity on 2025/06/22 07:20
android-5-15 BUG: soft lockup in __sock_create 1 18 556d 692d 0/2 auto-obsoleted due to no activity on 2024/11/30 09:28

Sample crash report:
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	1-....: (1 GPs behind) idle=a5d/1/0x4000000000000002 softirq=8357/8358 fqs=2099 
	(detected by 0, t=10504 jiffies, g=10141, q=1191)
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 5049 Comm: syz.2.241 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
RIP: 0010:check_kcov_mode kernel/kcov.c:172 [inline]
RIP: 0010:__sanitizer_cov_trace_pc+0x1b/0x60 kernel/kcov.c:206
Code: 89 de 5b e9 b7 41 44 00 00 00 cc cc 00 00 cc 48 8b 04 24 65 48 8b 0d a4 4e 89 7e 65 8b 15 a5 4e 89 7e 81 e2 00 01 ff 00 74 11 <81> fa 00 01 00 00 75 35 83 b9 34 16 00 00 00 74 2c 8b 91 10 16 00
RSP: 0018:ffffc90000dd08e0 EFLAGS: 00000006
RAX: ffffffff817f4f55 RBX: 0000000000000001 RCX: ffff88801de1d940
RDX: 0000000000000100 RSI: 0000000000000001 RDI: 0000000000000007
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
FS:  00007fdb5bfc56c0(0000) GS:ffff8880b9100000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000110c31a5f5 CR3: 000000005fab3000 CR4: 00000000003506e0
DR0: 0000200000000300 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
 <IRQ>
 cpu_max_bits_warn include/linux/cpumask.h:108 [inline]
 cpumask_check include/linux/cpumask.h:115 [inline]
 cpumask_test_cpu include/linux/cpumask.h:344 [inline]
 cpu_online include/linux/cpumask.h:895 [inline]
 trace_irq_disable include/trace/events/preemptirq.h:36 [inline]
 trace_hardirqs_off_finish+0x85/0x1f0 kernel/trace/trace_preemptirq.c:67
 irqentry_enter+0x33/0x50 kernel/entry/common.c:384
 sysvec_irq_work+0xa/0xc0 arch/x86/kernel/irq_work.c:17
 asm_sysvec_irq_work+0x16/0x20 arch/x86/include/asm/idtentry.h:713
RIP: 0010:rcu_read_unlock_special+0x7f/0x4a0 kernel/rcu/tree_plugin.h:674
Code: eb 03 48 b8 f1 f1 f1 f1 f8 f2 f2 f2 4a 89 04 2b 42 c7 44 2b 08 f8 f3 f3 f3 65 44 8b 35 12 f2 9c 7e 41 f7 c6 00 00 f0 00 74 40 <48> c7 44 24 20 0e 36 e0 45 4a c7 04 2b 00 00 00 00 42 c7 44 2b 08
RSP: 0018:ffffc90000dd09e0 EFLAGS: 00000206
RAX: d4ee7ed0d6f41500 RBX: 1ffff920001ba140 RCX: d4ee7ed0d6f41500
RDX: dffffc0000000000 RSI: ffffffff8a2b2780 RDI: ffffffff8a79f980
RBP: ffffc90000dd0ac0 R08: ffffffff901d41bf R09: 1ffffffff203a837
R10: dffffc0000000000 R11: fffffbfff203a838 R12: ffffffff8c322f00
R13: dffffc0000000000 R14: 0000000000000246 R15: 0000000000000002
 __rcu_read_unlock+0x78/0xd0 kernel/rcu/tree_plugin.h:422
 rcu_read_unlock include/linux/rcupdate.h:772 [inline]
 hsr_announce+0x29a/0x310 net/hsr/hsr_device.c:410
 call_timer_fn+0x17b/0x540 kernel/time/timer.c:1648
 expire_timers kernel/time/timer.c:1699 [inline]
 __run_timers+0x53e/0x800 kernel/time/timer.c:1970
 run_timer_softirq+0x63/0xf0 kernel/time/timer.c:1983
 handle_softirqs+0x339/0x830 kernel/softirq.c:576
 __do_softirq kernel/softirq.c:610 [inline]
 invoke_softirq kernel/softirq.c:450 [inline]
 __irq_exit_rcu+0x13b/0x230 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:preempt_schedule_irq+0xb6/0x160 kernel/sched/core.c:6799
Code: 00 00 43 c6 44 37 04 f8 74 0b 0f 0b 48 f7 03 08 00 00 00 74 7f bf 01 00 00 00 e8 85 ae 8d f7 e8 c0 9a ba f7 fb bf 01 00 00 00 <e8> 65 b5 ff ff 43 c6 44 37 08 00 48 c7 44 24 40 00 00 00 00 9c 8f
RSP: 0018:ffffc900032ef8e0 EFLAGS: 00000282
RAX: d4ee7ed0d6f41500 RBX: 0000000000000000 RCX: d4ee7ed0d6f41500
RDX: dffffc0000000000 RSI: ffffffff8a2b2780 RDI: 0000000000000001
RBP: ffffc900032ef980 R08: ffff8880b913b30b R09: 1ffff11017227661
R10: dffffc0000000000 R11: ffffed1017227662 R12: 0000000000000000
R13: 0000000000000000 R14: dffffc0000000000 R15: 1ffff9200065df1c
 irqentry_exit+0x63/0x70 kernel/entry/common.c:432
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676
RIP: 0010:put_cpu_partial+0x15e/0x190 mm/slub.c:2591
Code: 00 00 48 3b 44 24 08 75 4d 48 83 c4 10 5b 41 5c 41 5d 41 5e 41 5f 5d c3 e8 3f aa fe 07 41 f7 c5 00 02 00 00 74 c3 fb 4d 85 ff <75> c2 eb cb 48 c7 c7 d0 21 3f 8c 4c 89 e6 e8 5f 34 46 02 e9 e5 fe
RSP: 0018:ffffc900032efa48 EFLAGS: 00000246
RAX: d4ee7ed0d6f41500 RBX: ffff888016c41500 RCX: d4ee7ed0d6f41500
RDX: dffffc0000000000 RSI: ffffffff8a2b2780 RDI: ffffffff8a79f980
RBP: 0000000000000001 R08: ffff8880b913b30b R09: 1ffff11017227661
R10: dffffc0000000000 R11: ffffed1017227662 R12: 0000000000000001
R13: 0000000000000286 R14: ffff8880b913dd30 R15: 0000000000000000
 qlist_free_all+0x35/0x90 mm/kasan/quarantine.c:176
 kasan_quarantine_reduce+0x150/0x160 mm/kasan/quarantine.c:283
 __kasan_slab_alloc+0x2f/0xd0 mm/kasan/common.c:444
 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
 sock_alloc_inode+0x17/0xb0 net/socket.c:305
 alloc_inode fs/inode.c:261 [inline]
 new_inode_pseudo+0x5f/0x210 fs/inode.c:1001
 sock_alloc net/socket.c:628 [inline]
 __sock_create+0x129/0x900 net/socket.c:1459
 sock_create net/socket.c:1551 [inline]
 __sys_socketpair+0x1bd/0x540 net/socket.c:1651
 __do_sys_socketpair net/socket.c:1704 [inline]
 __se_sys_socketpair net/socket.c:1701 [inline]
 __x64_sys_socketpair+0x97/0xb0 net/socket.c:1701
 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: 0033:0x7fdb5dd6b799
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 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 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fdb5bfc5028 EFLAGS: 00000246 ORIG_RAX: 0000000000000035
RAX: ffffffffffffffda RBX: 00007fdb5dfe4fa0 RCX: 00007fdb5dd6b799
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000001
RBP: 00007fdb5de01bd9 R08: 0000000000000000 R09: 0000000000000000
R10: 0000200000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fdb5dfe5038 R14: 00007fdb5dfe4fa0 R15: 00007ffca1bcfa98
 </TASK>

Crashes (11):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/03/10 12:02 linux-5.15.y 91d48252ad4b 6972f302 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf INFO: rcu detected stall in __sock_create
2026/03/08 23:27 linux-5.15.y 91d48252ad4b 5cb44a80 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf INFO: rcu detected stall in __sock_create
2026/01/28 15:58 linux-5.15.y 9eec9a14ee10 004c195c .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf INFO: rcu detected stall in __sock_create
2025/12/22 15:09 linux-5.15.y 68efe5a6c16a d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf INFO: rcu detected stall in __sock_create
2025/12/15 17:24 linux-5.15.y 68efe5a6c16a d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf INFO: rcu detected stall in __sock_create
2025/12/04 19:39 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_create
2025/11/20 07:26 linux-5.15.y cc5ec8769306 26ee5237 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf INFO: rcu detected stall in __sock_create
2025/10/28 00:49 linux-5.15.y ac56c046adf4 fd2207e7 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf INFO: rcu detected stall in __sock_create
2025/09/20 08:53 linux-5.15.y 43bb85222e53 67c37560 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf INFO: rcu detected stall in __sock_create
2025/09/17 13:01 linux-5.15.y 43bb85222e53 e2beed91 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf INFO: rcu detected stall in __sock_create
2025/08/14 08:18 linux-5.15.y c79648372d02 22ec1469 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf INFO: rcu detected stall in __sock_create
* Struck through repros no longer work on HEAD.