[v5.15] INFO: rcu detected stall in tcp_setsockopt (3)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 241d66fa280c Linux 5.15.208
git tree: linux-5.15.y
console output: https://syzkaller.appspot.com/x/log.txt?x=1713127e580000
kernel config: https://syzkaller.appspot.com/x/.config?x=353ae28c40b35af5
dashboard link: https://syzkaller.appspot.com/bug?extid=485ab36ce0cc9e2b8859
compiler: Debian clang version 21.1.8 (++20251221033036+2078da43e25a-1~exp1~20251221153213.50), Debian LLD 21.1.8

Unfortunately, I don't have any reproducer for this issue yet.

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/aa5371307962/disk-241d66fa.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/df72e55b8c3c/vmlinux-241d66fa.xz
kernel image: https://storage.googleapis.com/syzbot-assets/96a6e7e64a47/bzImage-241d66fa.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+485ab3...@syzkaller.appspotmail.com

rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 1-...!: (1 GPs behind) idle=ca5/1/0x4000000000000000 softirq=16949/16950 fqs=3
(detected by 0, t=10502 jiffies, g=23197, q=87)
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 7220 Comm: syz.6.661 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
RIP: 0010:rcu_rnp_online_cpus kernel/rcu/tree.c:222 [inline]
RIP: 0010:rcu_lockdep_current_cpu_online+0xbd/0x130 kernel/rcu/tree.c:1173
Code: 20 4c 89 f0 48 c1 e8 03 42 80 3c 38 00 74 08 4c 89 f7 e8 56 71 59 00 4d 8b 26 4c 8d 73 70 4c 89 f0 48 c1 e8 03 42 80 3c 38 00 <74> 08 4c 89 f7 e8 39 71 59 00 4d 85 26 75 27 48 83 c3 78 48 89 d8
RSP: 0018:ffffc9000388ee68 EFLAGS: 00000046
RAX: 1ffffffff18646fe RBX: ffffffff8c323780 RCX: eba86f3121859f00
RDX: 0000000000000002 RSI: ffffffff8a7a06e0 RDI: ffff8880b913b1d8
RBP: ffffc9000388ef98 R08: dffffc0000000000 R09: 1ffffffff203ac18
R10: dffffc0000000000 R11: fffffbfff203ac19 R12: 0000000000000002
R13: dffffc0000000000 R14: ffffffff8c3237f0 R15: dffffc0000000000
FS: 00007f4ea6c546c0(0000) GS:ffff8880b9100000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fcb3285b158 CR3: 0000000077932000 CR4: 00000000003506e0
DR0: 0000200000000300 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
<TASK>
rcu_read_lock_held_common kernel/rcu/update.c:112 [inline]
rcu_read_lock_held+0x1a/0x40 kernel/rcu/update.c:309
BPF_PROG_RUN_ARRAY include/linux/bpf.h:1432 [inline]
trace_call_bpf+0x19c/0x5b0 kernel/trace/bpf_trace.c:127
perf_trace_run_bpf_submit+0x79/0x1c0 kernel/events/core.c:10016
perf_trace_preemptirq_template+0x2aa/0x360 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+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 d2 df 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:ffffc9000388f1c0 EFLAGS: 00000206
RAX: eba86f3121859f00 RBX: 1ffff92000711e3c RCX: eba86f3121859f00
RDX: dffffc0000000000 RSI: ffffffff8a2b3100 RDI: ffffffff8a7a0700
RBP: ffffc9000388f298 R08: ffffffff901d60c7 R09: 1ffffffff203ac18
R10: dffffc0000000000 R11: fffffbfff203ac19 R12: ffffffff8c323800
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]
pfn_valid include/linux/mmzone.h:-1 [inline]
__virt_addr_valid+0x3b8/0x470 arch/x86/mm/physaddr.c:65
free_pages+0x12/0x50 mm/page_alloc.c:5587
kasan_depopulate_vmalloc_pte+0x67/0x80 mm/kasan/shadow.c:375
apply_to_pte_range mm/memory.c:2573 [inline]
apply_to_pmd_range mm/memory.c:2617 [inline]
apply_to_pud_range mm/memory.c:2653 [inline]
apply_to_p4d_range mm/memory.c:2689 [inline]
__apply_to_page_range+0x983/0xd10 mm/memory.c:2725
kasan_release_vmalloc+0x93/0xb0 mm/kasan/shadow.c:485
__purge_vmap_area_lazy+0xafc/0x1950 mm/vmalloc.c:1711
_vm_unmap_aliases+0x410/0x4a0 mm/vmalloc.c:2114
change_page_attr_set_clr+0x323/0xca0 arch/x86/mm/pat/set_memory.c:1740
change_page_attr_clear arch/x86/mm/pat/set_memory.c:1797 [inline]
set_memory_x+0xd3/0x110 arch/x86/mm/pat/set_memory.c:1930
bpf_jit_binary_lock_ro include/linux/filter.h:920 [inline]
bpf_int_jit_compile+0xc6f0/0xcd80 arch/x86/net/bpf_jit_comp.c:2478
bpf_prog_select_runtime+0x46f/0x7c0 kernel/bpf/core.c:1977
bpf_prog_load+0x1017/0x1510 kernel/bpf/syscall.c:2358
__sys_bpf+0x532/0x6f0 kernel/bpf/syscall.c:4657
__do_sys_bpf kernel/bpf/syscall.c:4761 [inline]
__se_sys_bpf kernel/bpf/syscall.c:4759 [inline]
__x64_sys_bpf+0x78/0x90 kernel/bpf/syscall.c:4759
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: 0033:0x7f4ea89fae59
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:00007f4ea6c54028 EFLAGS: 00000246 ORIG_RAX: 0000000000000141
RAX: ffffffffffffffda RBX: 00007f4ea8c73fa0 RCX: 00007f4ea89fae59
RDX: 0000000000000048 RSI: 0000200000000200 RDI: 0000000000000005
RBP: 00007f4ea8a90d6f R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f4ea8c74038 R14: 00007f4ea8c73fa0 R15: 00007fff649f8c48
</TASK>
rcu: rcu_preempt kthread timer wakeup didn't happen for 10495 jiffies! g23197 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402
rcu: Possible timer handling issue on cpu=0 timer-softirq=14473
rcu: rcu_preempt kthread starved for 10496 jiffies! g23197 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->cpu=0
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:I stack:27384 pid: 15 ppid: 2 flags:0x00004000
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5049 [inline]
__schedule+0x11ef/0x43c0 kernel/sched/core.c:6395
schedule+0x11b/0x1e0 kernel/sched/core.c:6478
schedule_timeout+0x184/0x2d0 kernel/time/timer.c:2117
rcu_gp_fqs_loop+0x2be/0x11d0 kernel/rcu/tree.c:1972
rcu_gp_kthread+0x9b/0x370 kernel/rcu/tree.c:2145
kthread+0x436/0x520 kernel/kthread.c:334
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
</TASK>
rcu: Stack dump where RCU GP kthread last ran:
NMI backtrace for cpu 0
CPU: 0 PID: 4194 Comm: syz-executor Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
Call Trace:
<IRQ>
dump_stack_lvl+0x188/0x250 lib/dump_stack.c:106
nmi_cpu_backtrace+0x3a2/0x3d0 lib/nmi_backtrace.c:111
nmi_trigger_cpumask_backtrace+0x163/0x280 lib/nmi_backtrace.c:62
trigger_single_cpu_backtrace include/linux/nmi.h:166 [inline]
rcu_check_gp_kthread_starvation+0x1cd/0x250 kernel/rcu/tree_stall.h:487
print_other_cpu_stall+0x1110/0x1270 kernel/rcu/tree_stall.h:592
check_cpu_stall kernel/rcu/tree_stall.h:745 [inline]
rcu_pending kernel/rcu/tree.c:3936 [inline]
rcu_sched_clock_irq+0x843/0x1120 kernel/rcu/tree.c:2619
update_process_times+0x193/0x200 kernel/time/timer.c:2021
tick_sched_handle kernel/time/tick-sched.c:254 [inline]
tick_sched_timer+0x37d/0x560 kernel/time/tick-sched.c:1473
__run_hrtimer kernel/time/hrtimer.c:1685 [inline]
__hrtimer_run_queues+0x4b4/0xb70 kernel/time/hrtimer.c:1749
hrtimer_interrupt+0x3bb/0x8d0 kernel/time/hrtimer.c:1811
local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1097 [inline]
__sysvec_apic_timer_interrupt+0x137/0x4a0 arch/x86/kernel/apic/apic.c:1114
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1108 [inline]
sysvec_apic_timer_interrupt+0x9b/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:native_safe_halt arch/x86/include/asm/irqflags.h:51 [inline]
RIP: 0010:arch_safe_halt arch/x86/include/asm/irqflags.h:89 [inline]
RIP: 0010:kvm_wait+0x159/0x1b0 arch/x86/kernel/kvm.c:918
Code: 89 df 48 89 f8 48 c1 e8 03 42 0f b6 04 30 84 c0 75 4b 0f b6 1f e8 77 b8 4a 00 44 38 e3 75 10 66 90 0f 00 2d f9 db f3 08 fb f4 <e9> 16 ff ff ff fb e9 10 ff ff ff e8 27 30 88 08 89 f9 80 e1 07 38
RSP: 0018:ffffc90002e0ee60 EFLAGS: 00000246
RAX: cb62983171b96c00 RBX: 0000000000000003 RCX: cb62983171b96c00
RDX: dffffc0000000000 RSI: ffffffff8a2b3100 RDI: ffffffff8a7a0700
RBP: ffffc90002e0ef10 R08: ffffffff901d60c7 R09: 1ffffffff203ac18
R10: dffffc0000000000 R11: fffffbfff203ac19 R12: 0000000000000003
R13: ffff8880b903b154 R14: dffffc0000000000 R15: 1ffff920005c1dcc
pv_wait arch/x86/include/asm/paravirt.h:597 [inline]
pv_wait_head_or_lock kernel/locking/qspinlock_paravirt.h:470 [inline]
__pv_queued_spin_lock_slowpath+0x60f/0x9c0 kernel/locking/qspinlock.c:508
pv_queued_spin_lock_slowpath arch/x86/include/asm/paravirt.h:585 [inline]
queued_spin_lock_slowpath+0x43/0x50 arch/x86/include/asm/qspinlock.h:51
queued_spin_lock include/asm-generic/qspinlock.h:85 [inline]
do_raw_spin_lock+0x265/0x2f0 kernel/locking/spinlock_debug.c:115
spin_lock include/linux/spinlock.h:364 [inline]
preload_this_cpu_lock mm/vmalloc.c:1507 [inline]
alloc_vmap_area+0x23c/0x1a10 mm/vmalloc.c:1549
__get_vm_area_node+0x14f/0x2d0 mm/vmalloc.c:2430
__vmalloc_node_range+0xef/0x8b0 mm/vmalloc.c:3027
__vmalloc_node mm/vmalloc.c:3087 [inline]
vzalloc+0x75/0x80 mm/vmalloc.c:3157
__do_replace+0xab/0x9c0 net/ipv6/netfilter/ip6_tables.c:1065
do_replace net/ipv6/netfilter/ip6_tables.c:1160 [inline]
do_ip6t_set_ctl+0xaaa/0xd90 net/ipv6/netfilter/ip6_tables.c:1646
nf_setsockopt+0x25f/0x280 net/netfilter/nf_sockopt.c:101
ipv6_setsockopt+0x2086/0x3cc0 net/ipv6/ipv6_sockglue.c:1014
tcp_setsockopt+0x240/0x1e90 net/ipv4/tcp.c:3722
__sys_setsockopt+0x2bf/0x3d0 net/socket.c:2212
__do_sys_setsockopt net/socket.c:2223 [inline]
__se_sys_setsockopt net/socket.c:2220 [inline]
__x64_sys_setsockopt+0xb1/0xc0 net/socket.c:2220
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: 0033:0x7fcb3261169a
Code: 48 83 ec 10 48 63 c9 48 63 ff 45 89 c9 6a 2c e8 6c 99 fb ff 48 83 c4 18 c3 0f 1f 80 00 00 00 00 49 89 ca b8 36 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 06 c3 0f 1f 44 00 00 48 c7 c2 e8 ff ff ff f7
RSP: 002b:00007ffeb383f948 EFLAGS: 00000206 ORIG_RAX: 0000000000000036
RAX: ffffffffffffffda RBX: 00007ffeb383f9d0 RCX: 00007fcb3261169a
RDX: 0000000000000040 RSI: 0000000000000029 RDI: 0000000000000003
RBP: 0000000000000003 R08: 0000000000000558 R09: 0000000000000000
R10: 00007fcb3285cbe0 R11: 0000000000000206 R12: 00007fcb3285cb80
R13: 00007ffeb383f96c R14: 0000000000000000 R15: 00007fcb3285dfc0
</TASK>


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