syzbot

rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	0-...!: (3 ticks this GP) idle=2604/1/0x4000000000000000 softirq=41001/41001 fqs=0
rcu: 	(detected by 1, t=10502 jiffies, g=50313, q=1778 ncpus=2)
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 10918 Comm: syz.0.1758 Not tainted 6.6.101-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
RIP: 0010:perf_prepare_sample+0x5/0x1c40 kernel/events/core.c:7738
Code: c4 08 5b 41 5c 41 5d 41 5e 41 5f 5d c3 44 89 f1 80 e1 07 fe c1 38 c1 7c af 4c 89 f7 e8 54 a7 30 00 eb a5 66 90 f3 0f 1e fa 55 <48> 89 e5 41 57 41 56 41 55 41 54 53 48 83 e4 e0 48 81 ec c0 00 00
RSP: 0018:ffffc90000007410 EFLAGS: 00000046
RAX: ffffffff81ac57cb RBX: 0000000000000001 RCX: ffff88801cf65a00
RDX: ffff8880b8e36aa8 RSI: ffff888029bfcf38 RDI: ffffc90000007700
RBP: ffffc90000007528 R08: dffffc0000000000 R09: 1ffffffff21b46a4
R10: dffffc0000000000 R11: fffffbfff21b46a5 R12: 1ffff92000000e88
R13: ffff888029bfcf38 R14: ffffc90000007700 R15: ffffc90000007700
FS:  00007f487f4136c0(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000110c2c4589 CR3: 000000005b6f5000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000200000000300 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
 <IRQ>
 __perf_event_output kernel/events/core.c:7957 [inline]
 perf_event_output_forward+0x152/0x3a0 kernel/events/core.c:7978
 __perf_event_overflow+0x447/0x630 kernel/events/core.c:9703
 perf_swevent_overflow kernel/events/core.c:9779 [inline]
 perf_swevent_event+0x2f5/0x5c0 kernel/events/core.c:-1
 perf_tp_event+0x4f9/0x13a0 kernel/events/core.c:10329
 perf_trace_run_bpf_submit+0xf4/0x1c0 kernel/events/core.c:10253
 perf_trace_preemptirq_template+0x281/0x340 include/trace/events/preemptirq.h:14
 trace_irq_enable+0xbf/0xe0 include/trace/events/preemptirq.h:40
 trace_hardirqs_on+0x18/0x40 kernel/trace/trace_preemptirq.c:56
 asm_sysvec_irq_work+0x1a/0x20 arch/x86/include/asm/idtentry.h:723
RIP: 0010:rcu_read_unlock_special+0x88/0x4c0 kernel/rcu/tree_plugin.h:682
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 a9 4e 93 7e 41 f7 c6 00 00 f0 00 74 45 <48> c7 44 24 40 0e 36 e0 45 4a c7 04 2b 00 00 00 00 66 42 c7 44 2b
RSP: 0018:ffffc90000007b00 EFLAGS: 00000206
RAX: d06df1d7c3b9f600 RBX: 1ffff92000000f68 RCX: d06df1d7c3b9f600
RDX: dffffc0000000000 RSI: ffffffff8aaaba40 RDI: ffffffff8afc6780
RBP: ffffc90000007bf0 R08: ffffffff8e4a84ef R09: 1ffffffff1c9509d
R10: dffffc0000000000 R11: fffffbfff1c9509e R12: ffffffff8cd35400
R13: dffffc0000000000 R14: 0000000000000246 R15: 0000000000000001
 __rcu_read_unlock+0x7c/0xd0 kernel/rcu/tree_plugin.h:426
 rcu_read_unlock include/linux/rcupdate.h:818 [inline]
 ieee80211_iterate_active_interfaces_atomic+0x15a/0x180 net/mac80211/util.c:804
 mac80211_hwsim_beacon+0xbb/0x1b0 drivers/net/wireless/virtual/mac80211_hwsim.c:2295
 __run_hrtimer kernel/time/hrtimer.c:1755 [inline]
 __hrtimer_run_queues+0x51e/0xc40 kernel/time/hrtimer.c:1819
 hrtimer_run_softirq+0x187/0x2b0 kernel/time/hrtimer.c:1836
 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+0xc7/0x190 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:__kernel_text_address+0x0/0x30 kernel/extable.c:78
Code: 48 c7 c1 80 54 4a 8e 80 e1 07 80 c1 03 38 c1 7c c6 48 c7 c7 80 54 4a 8e e8 2d 65 84 00 eb b8 66 2e 0f 1f 84 00 00 00 00 00 90 <66> 0f 1f 00 53 48 89 fb e8 23 00 00 00 85 c0 0f 95 c0 48 81 fb 00
RSP: 0018:ffffc9000f5df838 EFLAGS: 00000246
RAX: ffffffff813aa157 RBX: ffffc9000f5df8b0 RCX: 0000000000000002
RDX: ffff88801cf65a00 RSI: 0000000000000001 RDI: ffffffff817470cc
RBP: 0000000000000001 R08: ffff88801cf65a00 R09: 0000000000000003
R10: 0000000000000004 R11: 0000000000000002 R12: ffff88801cf65a00
R13: 0000000000000780 R14: dffffc0000000000 R15: 1ffff92001ebbf16
 unwind_get_return_address+0x5d/0xc0 arch/x86/kernel/unwind_orc.c:369
 arch_stack_walk+0x11d/0x190 arch/x86/kernel/stacktrace.c:26
 stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122
 kasan_save_stack mm/kasan/common.c:45 [inline]
 kasan_set_track+0x4e/0x70 mm/kasan/common.c:52
 __kasan_slab_alloc+0x6c/0x80 mm/kasan/common.c:328
 kasan_slab_alloc include/linux/kasan.h:188 [inline]
 slab_post_alloc_hook+0x6e/0x4d0 mm/slab.h:767
 slab_alloc_node mm/slub.c:3485 [inline]
 slab_alloc mm/slub.c:3493 [inline]
 __kmem_cache_alloc_lru mm/slub.c:3500 [inline]
 kmem_cache_alloc+0x11e/0x2e0 mm/slub.c:3509
 sk_prot_alloc+0x57/0x210 net/core/sock.c:2088
 sk_alloc+0x3a/0x360 net/core/sock.c:2147
 unix_create1+0xb0/0x790 net/unix/af_unix.c:-1
 unix_create+0x154/0x1f0 net/unix/af_unix.c:1084
 __sock_create+0x4a6/0x940 net/socket.c:1571
 sock_create net/socket.c:1627 [inline]
 __sys_socketpair+0x1c1/0x550 net/socket.c:1778
 __do_sys_socketpair net/socket.c:1831 [inline]
 __se_sys_socketpair net/socket.c:1828 [inline]
 __x64_sys_socketpair+0x9b/0xb0 net/socket.c:1828
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f487e58ebe9
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:00007f487f413038 EFLAGS: 00000246 ORIG_RAX: 0000000000000035
RAX: ffffffffffffffda RBX: 00007f487e7b5fa0 RCX: 00007f487e58ebe9
RDX: 0000000000000000 RSI: 0000000000000005 RDI: 0000000000000001
RBP: 00007f487e611e19 R08: 0000000000000000 R09: 0000000000000000
R10: 0000200000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f487e7b6038 R14: 00007f487e7b5fa0 R15: 00007ffe815ebfb8
 </TASK>
rcu: rcu_preempt kthread timer wakeup didn't happen for 10501 jiffies! g50313 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402
rcu: 	Possible timer handling issue on cpu=0 timer-softirq=37582
rcu: rcu_preempt kthread starved for 10502 jiffies! g50313 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:26776 pid:17    ppid:2      flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5381 [inline]
 __schedule+0x14d2/0x44d0 kernel/sched/core.c:6700
 schedule+0xbd/0x170 kernel/sched/core.c:6774
 schedule_timeout+0x160/0x280 kernel/time/timer.c:2167
 rcu_gp_fqs_loop+0x302/0x1560 kernel/rcu/tree.c:1667
 rcu_gp_kthread+0x99/0x380 kernel/rcu/tree.c:1866
 kthread+0x2fa/0x390 kernel/kthread.c:388
 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152
 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 10918 Comm: syz.0.1758 Not tainted 6.6.101-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
RIP: 0010:asm_sysvec_irq_work+0x0/0x20 arch/x86/include/asm/idtentry.h:723
Code: 66 f5 ec ff e9 a1 03 00 00 90 f3 0f 1e fa 0f 01 ca fc 6a ff e8 a1 02 00 00 48 89 c4 48 89 e7 e8 56 d7 ec ff e9 81 03 00 00 90 <f3> 0f 1e fa 0f 01 ca fc 6a ff e8 81 02 00 00 48 89 c4 48 89 e7 e8
RSP: 0018:ffffc90000007ad8 EFLAGS: 00000006
RAX: d06df1d7c3b9f600 RBX: 1ffff92000000f68 RCX: d06df1d7c3b9f600
RDX: dffffc0000000000 RSI: ffffffff8aaaba40 RDI: ffffffff8afc6780
RBP: ffffc90000007bf0 R08: ffffffff8e4a84ef R09: 1ffffffff1c9509d
R10: dffffc0000000000 R11: fffffbfff1c9509e R12: ffffffff8cd35400
R13: dffffc0000000000 R14: 0000000000000246 R15: 0000000000000001
FS:  00007f487f4136c0(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000110c2c4589 CR3: 000000005b6f5000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000200000000300 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
 <IRQ>
RIP: 0010:rcu_read_unlock_special+0x88/0x4c0 kernel/rcu/tree_plugin.h:682
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 a9 4e 93 7e 41 f7 c6 00 00 f0 00 74 45 <48> c7 44 24 40 0e 36 e0 45 4a c7 04 2b 00 00 00 00 66 42 c7 44 2b
RSP: 0018:ffffc90000007b00 EFLAGS: 00000206
 __rcu_read_unlock+0x7c/0xd0 kernel/rcu/tree_plugin.h:426
 rcu_read_unlock include/linux/rcupdate.h:818 [inline]
 ieee80211_iterate_active_interfaces_atomic+0x15a/0x180 net/mac80211/util.c:804
 mac80211_hwsim_beacon+0xbb/0x1b0 drivers/net/wireless/virtual/mac80211_hwsim.c:2295
 __run_hrtimer kernel/time/hrtimer.c:1755 [inline]
 __hrtimer_run_queues+0x51e/0xc40 kernel/time/hrtimer.c:1819
 hrtimer_run_softirq+0x187/0x2b0 kernel/time/hrtimer.c:1836
 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+0xc7/0x190 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:__kernel_text_address+0x0/0x30 kernel/extable.c:78
Code: 48 c7 c1 80 54 4a 8e 80 e1 07 80 c1 03 38 c1 7c c6 48 c7 c7 80 54 4a 8e e8 2d 65 84 00 eb b8 66 2e 0f 1f 84 00 00 00 00 00 90 <66> 0f 1f 00 53 48 89 fb e8 23 00 00 00 85 c0 0f 95 c0 48 81 fb 00
RSP: 0018:ffffc9000f5df838 EFLAGS: 00000246
RAX: ffffffff813aa157 RBX: ffffc9000f5df8b0 RCX: 0000000000000002
RDX: ffff88801cf65a00 RSI: 0000000000000001 RDI: ffffffff817470cc
RBP: 0000000000000001 R08: ffff88801cf65a00 R09: 0000000000000003
R10: 0000000000000004 R11: 0000000000000002 R12: ffff88801cf65a00
R13: 0000000000000780 R14: dffffc0000000000 R15: 1ffff92001ebbf16
 unwind_get_return_address+0x5d/0xc0 arch/x86/kernel/unwind_orc.c:369
 arch_stack_walk+0x11d/0x190 arch/x86/kernel/stacktrace.c:26
 stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122
 kasan_save_stack mm/kasan/common.c:45 [inline]
 kasan_set_track+0x4e/0x70 mm/kasan/common.c:52
 __kasan_slab_alloc+0x6c/0x80 mm/kasan/common.c:328
 kasan_slab_alloc include/linux/kasan.h:188 [inline]
 slab_post_alloc_hook+0x6e/0x4d0 mm/slab.h:767
 slab_alloc_node mm/slub.c:3485 [inline]
 slab_alloc mm/slub.c:3493 [inline]
 __kmem_cache_alloc_lru mm/slub.c:3500 [inline]
 kmem_cache_alloc+0x11e/0x2e0 mm/slub.c:3509
 sk_prot_alloc+0x57/0x210 net/core/sock.c:2088
 sk_alloc+0x3a/0x360 net/core/sock.c:2147
 unix_create1+0xb0/0x790 net/unix/af_unix.c:-1
 unix_create+0x154/0x1f0 net/unix/af_unix.c:1084
 __sock_create+0x4a6/0x940 net/socket.c:1571
 sock_create net/socket.c:1627 [inline]
 __sys_socketpair+0x1c1/0x550 net/socket.c:1778
 __do_sys_socketpair net/socket.c:1831 [inline]
 __se_sys_socketpair net/socket.c:1828 [inline]
 __x64_sys_socketpair+0x9b/0xb0 net/socket.c:1828
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f487e58ebe9
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:00007f487f413038 EFLAGS: 00000246 ORIG_RAX: 0000000000000035
RAX: ffffffffffffffda RBX: 00007f487e7b5fa0 RCX: 00007f487e58ebe9
RDX: 0000000000000000 RSI: 0000000000000005 RDI: 0000000000000001
RBP: 00007f487e611e19 R08: 0000000000000000 R09: 0000000000000000
R10: 0000200000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f487e7b6038 R14: 00007f487e7b5fa0 R15: 00007ffe815ebfb8
 </TASK>