INFO: rcu detected stall in sys_setsockopt

Status: upstream: reported on 2026/02/13 08:47
Reported-by: syzbot+035e355f20769f1e35a0@syzkaller.appspotmail.com
First crash: 245d, last: 7d13h
▶ ▼ Similar bugs (5)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: rcu detected stall in sys_setsockopt (2) kvm 1 2 1905d 1947d 0/29 auto-closed as invalid on 2021/10/27 00:02
upstream INFO: rcu detected stall in sys_setsockopt kvm 1 1 2067d 2067d 0/29 auto-closed as invalid on 2021/05/17 17:51
upstream INFO: rcu detected stall in sys_setsockopt (4) prio:high mm 1 syz, C done inconclusive 121 11h14m 690d 0/29 upstream: reported C repro on 2024/11/25 08:53
upstream INFO: rcu detected stall in sys_setsockopt (3) net 1 4 1778d 1805d 0/29 closed as invalid on 2022/02/08 10:00
linux-4.19 BUG: soft lockup in sys_setsockopt 1 3 2000d 2028d 0/1 auto-closed as invalid on 2021/08/23 07:10

Sample crash report:
IPVS: wrr: UDP 224.0.0.2:0 - no destination available
IPVS: wrr: UDP 224.0.0.2:0 - no destination available
IPVS: wrr: UDP 224.0.0.2:0 - no destination available
IPVS: wrr: UDP 224.0.0.2:0 - no destination available
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	1-...0: (1 GPs behind) idle=b56c/1/0x4000000000000000 softirq=57994/57995 fqs=5249
rcu: 	         hardirqs   softirqs   csw/system
rcu: 	 number:        0          0            0
rcu: 	cputime:        0          0            0   ==> 52510(ms)
rcu: 	(detected by 0, t=10502 jiffies, g=74537, q=744 ncpus=2)
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 17218 Comm: syz.3.2982 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/16/2026
RIP: 0010:__sanitizer_cov_trace_pc+0x0/0x60 kernel/kcov.c:208
Code: 00 0f 0b 0f 1f 80 00 00 00 00 f3 0f 1e fa 53 48 89 fb e8 13 00 00 00 48 8b 3d 7c cc e4 0d 48 89 de 5b e9 73 10 58 00 cc cc cc <f3> 0f 1e fa 48 8b 04 24 65 48 8b 0d 40 27 7c 7e 65 8b 15 41 27 7c
RSP: 0018:ffffc900001f0d58 EFLAGS: 00000097
RAX: ffffffff81777ea3 RBX: 0000000000000001 RCX: 0000000000010000
RDX: ffff88804e7cda00 RSI: 0000000000000001 RDI: 0000000000000007
RBP: ffffc900001f0eb8 R08: ffff8880b8d2b743 R09: 1ffff110171a56e8
R10: dffffc0000000000 R11: ffffed10171a56e9 R12: ffffffff88b9c010
R13: ffff88807df5b340 R14: ffff8880b8d2b988 R15: dffffc0000000000
FS:  00007f259f6916c0(0000) GS:ffff8880b8d00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000200000047000 CR3: 000000003fca8000 CR4: 00000000003506e0
DR0: 0000000000010000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
 <IRQ>
 cpu_max_bits_warn include/linux/cpumask.h:143 [inline]
 cpumask_check include/linux/cpumask.h:150 [inline]
 cpumask_test_cpu include/linux/cpumask.h:504 [inline]
 cpu_online include/linux/cpumask.h:1082 [inline]
 trace_hrtimer_expire_entry include/trace/events/timer.h:242 [inline]
 __run_hrtimer kernel/time/hrtimer.c:1751 [inline]
 __hrtimer_run_queues+0x451/0xc10 kernel/time/hrtimer.c:1818
 hrtimer_interrupt+0x39d/0x980 kernel/time/hrtimer.c:1880
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1077 [inline]
 __sysvec_apic_timer_interrupt+0xfb/0x3b0 arch/x86/kernel/apic/apic.c:1094
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1088 [inline]
 sysvec_apic_timer_interrupt+0x9f/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:lock_acquire+0x208/0x420 kernel/locking/lockdep.c:5794
Code: f7 84 24 80 00 00 00 00 02 00 00 43 c6 44 3c 04 f8 0f 85 f0 00 00 00 41 f7 c6 00 02 00 00 74 01 fb 48 c7 44 24 60 0e 36 e0 45 <4b> c7 04 3c 00 00 00 00 43 c7 44 3c 08 00 00 00 00 65 48 8b 04 25
RSP: 0018:ffffc900037ffac0 EFLAGS: 00000206
RAX: 0000000000000001 RBX: 0000000000000000 RCX: b8380cebe6a55400
RDX: 0000000000000000 RSI: ffffffff8acae160 RDI: ffffffff8b1d5160
RBP: ffffc900037ffbc8 R08: dffffc0000000000 R09: 1ffffffff23fe2a6
R10: dffffc0000000000 R11: fffffbfff23fe2a7 R12: 1ffff920006fff64
R13: ffff88803736baa0 R14: 0000000000000246 R15: dffffc0000000000
 __might_fault+0xc6/0x120 mm/memory.c:5968
 _copy_from_user+0x2a/0xe0 lib/usercopy.c:14
 copy_from_user include/linux/uaccess.h:183 [inline]
 copy_from_sockptr_offset include/linux/sockptr.h:48 [inline]
 tcp_repair_options_est+0x103/0x410 net/ipv4/tcp.c:3199
 do_tcp_setsockopt+0x16f5/0x1c50 net/ipv4/tcp.c:3636
 do_sock_setsockopt+0x175/0x1a0 net/socket.c:2322
 __sys_setsockopt net/socket.c:2345 [inline]
 __do_sys_setsockopt net/socket.c:2354 [inline]
 __se_sys_setsockopt net/socket.c:2351 [inline]
 __x64_sys_setsockopt+0x182/0x200 net/socket.c:2351
 do_syscall_x64 arch/x86/entry/common.c:46 [inline]
 do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:76
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f259e79e1d9
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:00007f259f691028 EFLAGS: 00000246 ORIG_RAX: 0000000000000036
RAX: ffffffffffffffda RBX: 00007f259ea25fa0 RCX: 00007f259e79e1d9
RDX: 0000000000000016 RSI: 0000000000000006 RDI: 0000000000000003
RBP: 00007f259e835888 R08: 0000000020000328 R09: 0000000000000000
R10: 0000200000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f259ea26038 R14: 00007f259ea25fa0 R15: 00007ffca1de53f8
 </TASK>
IPVS: wrr: UDP 224.0.0.2:0 - no destination available
IPVS: wrr: UDP 224.0.0.2:0 - no destination available
IPVS: wrr: UDP 224.0.0.2:0 - no destination available
IPVS: wrr: UDP 224.0.0.2:0 - no destination available
IPVS: wrr: UDP 224.0.0.2:0 - no destination available
IPVS: wrr: UDP 224.0.0.2:0 - no destination available
IPVS: wrr: UDP 224.0.0.2:0 - no destination available
IPVS: wrr: UDP 224.0.0.2:0 - no destination available
IPVS: wrr: UDP 224.0.0.2:0 - no destination available

Crashes (5):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/10/08 22:16 linux-6.6.y a91a6aa9253c b2734a59 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan INFO: rcu detected stall in sys_setsockopt
2026/08/03 05:22 linux-6.6.y a1153c0deb44 e611ffe1 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan-perf INFO: rcu detected stall in sys_setsockopt
2026/06/24 15:42 linux-6.6.y d1cfde2d5d15 302586aa .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan INFO: rcu detected stall in sys_setsockopt
2026/05/21 03:26 linux-6.6.y eac8889a3a1c 41b8c833 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan INFO: rcu detected stall in sys_setsockopt
2026/02/13 08:46 linux-6.6.y 1b4ef5214f17 6a673c50 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan-perf INFO: rcu detected stall in sys_setsockopt
* Struck through repros no longer work on HEAD.