syzbot


INFO: rcu detected stall in sys_socket

Status: upstream: reported on 2025/07/12 12:18
Reported-by: syzbot+3a18ae63a3331d652199@syzkaller.appspotmail.com
First crash: 293d, last: 8h15m
Similar bugs (16)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: rcu detected stall in sys_socket (4) fs 1 1 1829d 1829d 0/29 auto-closed as invalid on 2021/07/27 17:27
linux-5.15 INFO: rcu detected stall in sys_socket 1 1 941d 941d 0/3 auto-obsoleted due to no activity on 2024/01/11 06:48
upstream INFO: rcu detected stall in sys_socket (5) net 1 2 1667d 1692d 0/29 auto-closed as invalid on 2022/01/06 01:08
upstream INFO: rcu detected stall in sys_socket mm 1 11 2340d 2341d 0/29 closed as invalid on 2019/12/04 14:04
linux-4.19 INFO: rcu detected stall in sys_socket 1 1 1470d 1470d 0/1 auto-closed as invalid on 2022/08/20 07:08
upstream INFO: rcu detected stall in sys_socket (10) mm 1 C done 229 5d19h 883d 0/29 upstream: reported C repro on 2023/11/30 15:24
linux-6.1 INFO: rcu detected stall in sys_socket 1 2 634d 635d 0/3 auto-obsoleted due to no activity on 2024/11/13 04:32
linux-6.1 INFO: rcu detected stall in sys_socket (3) origin:lts-only 1 C inconclusive 45 5d01h 235d 0/3 upstream: reported C repro on 2025/09/09 01:58
upstream INFO: rcu detected stall in sys_socket (6) cgroups mm 1 2 1326d 1370d 0/29 auto-obsoleted due to no activity on 2022/12/12 22:48
upstream INFO: rcu detected stall in sys_socket (7) kernel 1 2 1185d 1217d 0/29 auto-obsoleted due to no activity on 2023/05/02 14:50
linux-6.1 INFO: rcu detected stall in sys_socket (2) 1 3 424d 478d 0/3 auto-obsoleted due to no activity on 2025/06/11 16:02
upstream INFO: rcu detected stall in sys_socket (9) mm kasan 1 2 1002d 1012d 0/29 closed as invalid on 2023/09/07 14:25
upstream INFO: rcu detected stall in sys_socket (2) mm 1 3 2306d 2306d 0/29 closed as invalid on 2020/01/08 05:23
linux-5.15 INFO: rcu detected stall in sys_socket (2) origin:upstream 1 C error 63 2d15h 790d 0/3 upstream: reported C repro on 2024/03/02 17:55
upstream INFO: rcu detected stall in sys_socket (3) mm 1 4 2305d 2305d 0/29 closed as invalid on 2020/01/09 08:13
android-5-15 BUG: soft lockup in sys_socket 1 C error 26 602d 751d 0/2 auto-obsoleted due to no activity on 2024/11/29 22:24

Sample crash report:
rcu: INFO: rcu_preempt self-detected stall on CPU
rcu: 	1-....: (10458 ticks this GP) idle=bb5c/1/0x4000000000000000 softirq=79839/79839 fqs=5239
rcu: 	         hardirqs   softirqs   csw/system
rcu: 	 number:  1254747          0            0
rcu: 	cputime:    18024      34455           69   ==> 52490(ms)
rcu: 	(t=10501 jiffies g=105461 q=454 ncpus=2)
CPU: 1 PID: 20256 Comm: syz.1.4741 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
RIP: 0010:arch_static_branch arch/x86/include/asm/jump_label.h:27 [inline]
RIP: 0010:static_key_false include/linux/jump_label.h:207 [inline]
RIP: 0010:native_write_msr arch/x86/include/asm/msr.h:147 [inline]
RIP: 0010:wrmsr arch/x86/include/asm/msr.h:254 [inline]
RIP: 0010:native_apic_msr_write+0x39/0x50 arch/x86/include/asm/apic.h:196
Code: 74 2a 83 ff 30 74 25 eb 10 81 ff d0 00 00 00 74 1b 81 ff e0 00 00 00 74 13 c1 ef 04 81 c7 00 08 00 00 89 f9 89 f0 31 d2 0f 30 <66> 90 c3 89 f6 31 d2 e9 7b f8 23 03 66 2e 0f 1f 84 00 00 00 00 00
RSP: 0018:ffffc900001f0638 EFLAGS: 00000246
RAX: 00000000000000f6 RBX: 0000000000000200 RCX: 000000000000083f
RDX: 0000000000000000 RSI: 00000000000000f6 RDI: 000000000000083f
RBP: 0000000000000000 R08: ffffc900001f05a7 R09: 1ffff9200003e0b4
R10: dffffc0000000000 R11: fffff5200003e0b5 R12: 0000000000000001
R13: 0000000000000001 R14: ffffffff8d22e3e8 R15: 0000000000000020
FS:  00007efdd05d56c0(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fd6b534da08 CR3: 000000007effa000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000200000000300 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
 <IRQ>
 __apic_send_IPI_self arch/x86/include/asm/apic.h:454 [inline]
 arch_irq_work_raise+0x68/0x70 arch/x86/kernel/irq_work.c:31
 irq_work_queue+0x99/0x140 kernel/irq_work.c:124
 __kfence_alloc+0x2a0/0x3d0 mm/kfence/core.c:1126
 kfence_alloc include/linux/kfence.h:129 [inline]
 slab_alloc_node mm/slub.c:3481 [inline]
 kmem_cache_alloc_node+0x2b4/0x320 mm/slub.c:3540
 kmalloc_reserve+0x95/0x240 net/core/skbuff.c:562
 __alloc_skb+0x138/0x2c0 net/core/skbuff.c:653
 alloc_skb include/linux/skbuff.h:1316 [inline]
 ndisc_alloc_skb+0xa6/0x450 net/ipv6/ndisc.c:423
 ndisc_send_rs+0x2a6/0x610 net/ipv6/ndisc.c:707
 addrconf_rs_timer+0x2d5/0x630 net/ipv6/addrconf.c:4024
 call_timer_fn+0x189/0x540 kernel/time/timer.c:1701
 expire_timers kernel/time/timer.c:1752 [inline]
 __run_timers+0x542/0x800 kernel/time/timer.c:2023
 run_timer_softirq+0x67/0xf0 kernel/time/timer.c:2036
 handle_softirqs+0x280/0x820 kernel/softirq.c:578
 __do_softirq kernel/softirq.c:612 [inline]
 invoke_softirq kernel/softirq.c:452 [inline]
 __irq_exit_rcu+0xd3/0x190 kernel/softirq.c:661
 irq_exit_rcu+0x9/0x20 kernel/softirq.c:673
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1088 [inline]
 sysvec_apic_timer_interrupt+0xa4/0xc0 arch/x86/kernel/apic/apic.c:1088
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:687
RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline]
RIP: 0010:_raw_spin_unlock_irqrestore+0xc0/0x120 kernel/locking/spinlock.c:194
Code: c7 44 24 20 00 00 00 00 9c 8f 44 24 20 f7 44 24 20 00 02 00 00 41 c6 04 07 f8 75 4b f7 c3 00 02 00 00 74 01 fb bf 01 00 00 00 <e8> 0b 74 cc f6 65 8b 05 4c a1 73 75 85 c0 74 3c 48 c7 04 24 0e 36
RSP: 0018:ffffc9000475fae0 EFLAGS: 00000206
RAX: dffffc0000000004 RBX: 0000000000000a06 RCX: 722658736d199e00
RDX: dffffc0000000000 RSI: ffffffff8acac9e0 RDI: 0000000000000001
RBP: ffffc9000475fb68 R08: ffffffff911c652f R09: 1ffffffff2238ca5
R10: dffffc0000000000 R11: fffffbfff2238ca6 R12: dffffc0000000000
R13: 0000000000000000 R14: ffff888017c409c0 R15: 1ffff920008ebf5c
 spin_unlock_irqrestore include/linux/spinlock.h:406 [inline]
 __unfreeze_partials+0x190/0x210 mm/slub.c:2660
 put_cpu_partial+0x17c/0x250 mm/slub.c:2743
 __slab_free+0x319/0x400 mm/slub.c:3700
 qlink_free mm/kasan/quarantine.c:166 [inline]
 qlist_free_all+0x75/0xd0 mm/kasan/quarantine.c:185
 kasan_quarantine_reduce+0x143/0x160 mm/kasan/quarantine.c:292
 __kasan_slab_alloc+0x22/0x80 mm/kasan/common.c:306
 kasan_slab_alloc include/linux/kasan.h:188 [inline]
 slab_post_alloc_hook+0x6e/0x4b0 mm/slab.h:767
 slab_alloc_node mm/slub.c:3495 [inline]
 slab_alloc mm/slub.c:3503 [inline]
 __kmem_cache_alloc_lru mm/slub.c:3510 [inline]
 kmem_cache_alloc_lru+0x111/0x2d0 mm/slub.c:3526
 alloc_inode_sb include/linux/fs.h:2946 [inline]
 sock_alloc_inode+0x28/0xc0 net/socket.c:308
 alloc_inode fs/inode.c:261 [inline]
 new_inode_pseudo+0x63/0x1d0 fs/inode.c:1049
 sock_alloc net/socket.c:634 [inline]
 __sock_create+0x12d/0x940 net/socket.c:1534
 sock_create net/socket.c:1626 [inline]
 __sys_socket_create net/socket.c:1663 [inline]
 __sys_socket+0xd7/0x1a0 net/socket.c:1714
 __do_sys_socket net/socket.c:1728 [inline]
 __se_sys_socket net/socket.c:1726 [inline]
 __x64_sys_socket+0x7a/0x90 net/socket.c:1726
 do_syscall_x64 arch/x86/entry/common.c:46 [inline]
 do_syscall_64+0x55/0xa0 arch/x86/entry/common.c:76
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7efdd239cdd9
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:00007efdd05d5028 EFLAGS: 00000246 ORIG_RAX: 0000000000000029
RAX: ffffffffffffffda RBX: 00007efdd2616090 RCX: 00007efdd239cdd9
RDX: 0000000000000000 RSI: 0000000000000002 RDI: 0000000000000010
RBP: 00007efdd2432d69 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007efdd2616128 R14: 00007efdd2616090 R15: 00007ffe2ecde3c8
 </TASK>

Crashes (18):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/05/01 19:55 linux-6.6.y 258cf62a6dfd 753c55b9 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan-perf INFO: rcu detected stall in sys_socket
2026/05/01 12:12 linux-6.6.y 258cf62a6dfd 753c55b9 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan-perf INFO: rcu detected stall in sys_socket
2026/04/23 20:13 linux-6.6.y 9760bf04666d 4c3406dc .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan-perf INFO: rcu detected stall in sys_socket
2026/03/27 20:24 linux-6.6.y c09fbcd31ae6 74a13a23 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan-perf INFO: rcu detected stall in sys_socket
2026/03/07 22:54 linux-6.6.y 4fc00fe35d46 5cb44a80 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan INFO: rcu detected stall in sys_socket
2026/01/29 06:54 linux-6.6.y cbb31f77b879 0adc945e .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan-perf INFO: rcu detected stall in sys_socket
2026/01/07 12:09 linux-6.6.y 5fa4793a2d2d d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan INFO: rcu detected stall in sys_socket
2025/12/20 01:03 linux-6.6.y 5fa4793a2d2d d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan-perf INFO: rcu detected stall in sys_socket
2025/12/11 06:11 linux-6.6.y 5fa4793a2d2d d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan-perf INFO: rcu detected stall in sys_socket
2025/11/27 11:58 linux-6.6.y 1e89a1be4fe9 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan-perf INFO: rcu detected stall in sys_socket
2025/11/19 02:31 linux-6.6.y 0a805b6ea8cd ef766cd7 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan-perf INFO: rcu detected stall in sys_socket
2025/10/27 01:47 linux-6.6.y 4a243110dc88 c0460fcd .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan-perf INFO: rcu detected stall in sys_socket
2025/10/03 21:37 linux-6.6.y f34f16e5c632 49379ee0 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan INFO: rcu detected stall in sys_socket
2025/08/28 14:20 linux-6.6.y bb9c90ab9c5a e12e5ba4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan-perf INFO: rcu detected stall in sys_socket
2025/08/28 11:58 linux-6.6.y bb9c90ab9c5a e12e5ba4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan-perf INFO: rcu detected stall in sys_socket
2025/08/25 14:44 linux-6.6.y bb9c90ab9c5a bf27483f .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan-perf INFO: rcu detected stall in sys_socket
2025/08/06 11:41 linux-6.6.y 3a8ababb8b6a ffe1dd46 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan-perf INFO: rcu detected stall in sys_socket
2025/07/12 12:18 linux-6.6.y 59a2de10b81a 3cda49cf .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan INFO: rcu detected stall in sys_socket
* Struck through repros no longer work on HEAD.