rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	0-...!: (1 GPs behind) idle=34ec/1/0x4000000000000000 softirq=55662/55663 fqs=1
rcu: 	(detected by 1, t=10506 jiffies, g=44017, q=375 ncpus=2)
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 1219 Comm: kworker/0:3 Not tainted 6.15.0-rc7-syzkaller-00014-gd608703fcdd9 #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Workqueue: usb_hub_wq hub_event
RIP: 0010:preempt_count arch/x86/include/asm/preempt.h:27 [inline]
RIP: 0010:check_kcov_mode kernel/kcov.c:183 [inline]
RIP: 0010:write_comp_data+0x11/0x90 kernel/kcov.c:246
Code: b4 09 0f 1f 80 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 49 89 d2 49 89 f8 49 89 f1 65 48 8b 15 97 20 e9 11 <65> 8b 05 a8 20 e9 11 a9 00 01 ff 00 74 1d f6 c4 01 74 67 a9 00 00
RSP: 0000:ffffc90000007c40 EFLAGS: 00000046
RAX: dffffc0000000000 RBX: ffff8880581f3340 RCX: ffffffff8b695de0
RDX: ffff8880286d8000 RSI: 0000000000000001 RDI: 0000000000000006
RBP: ffff8880b8427990 R08: 0000000000000006 R09: 0000000000000001
R10: ffff8880581f3340 R11: 0000000000000000 R12: 0000000000000001
R13: 0000000000000000 R14: ffff8880b8427840 R15: 0000000000000000
FS:  0000000000000000(0000) GS:ffff8881249da000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000110c2a6cdf CR3: 00000000330ac000 CR4: 00000000003526f0
DR0: 0100000100000000 DR1: 0000000000000006 DR2: 0000000000000005
DR3: 0000000000000011 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 timerqueue_del+0x40/0x150 lib/timerqueue.c:55
 __remove_hrtimer+0x99/0x290 kernel/time/hrtimer.c:1121
 __run_hrtimer kernel/time/hrtimer.c:1741 [inline]
 __hrtimer_run_queues+0x4f9/0xad0 kernel/time/hrtimer.c:1825
 hrtimer_interrupt+0x397/0x8e0 kernel/time/hrtimer.c:1887
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1038 [inline]
 __sysvec_apic_timer_interrupt+0x108/0x3f0 arch/x86/kernel/apic/apic.c:1055
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1049 [inline]
 sysvec_apic_timer_interrupt+0x52/0xc0 arch/x86/kernel/apic/apic.c:1049
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:handle_softirqs+0x1dd/0x8e0 kernel/softirq.c:565
Code: 88 6c 24 26 4c 89 7c 24 18 48 c7 c7 a0 89 8b 8b e8 68 6e f0 09 65 66 c7 05 d6 91 27 12 00 00 e8 19 3c 46 00 fb bb ff ff ff ff <49> c7 c7 c0 c0 00 8e 41 0f bc dc 83 c3 01 0f 85 a4 00 00 00 e9 b1
RSP: 0000:ffffc90000007f28 EFLAGS: 00000202
RAX: 0000000000144dea RBX: 00000000ffffffff RCX: 0000000000000002
RDX: 0000000000000000 RSI: ffffffff8dbe4615 RDI: ffffffff8bf4a2e0
RBP: 0000000000000000 R08: 0000000000000001 R09: 0000000000000001
R10: ffffffff90852e17 R11: 0000000000000000 R12: 0000000000000100
R13: 000000000000000a R14: 1ffff92000000fed R15: ffffed10050db000
 __do_softirq kernel/softirq.c:613 [inline]
 invoke_softirq kernel/softirq.c:453 [inline]
 __irq_exit_rcu+0x109/0x170 kernel/softirq.c:680
 irq_exit_rcu+0x9/0x30 kernel/softirq.c:696
 instr_sysvec_call_function_single arch/x86/kernel/smp.c:266 [inline]
 sysvec_call_function_single+0xa4/0xc0 arch/x86/kernel/smp.c:266
 </IRQ>
 <TASK>
 asm_sysvec_call_function_single+0x1a/0x20 arch/x86/include/asm/idtentry.h:709
RIP: 0010:console_flush_all+0x9a2/0xc60 kernel/printk/printk.c:3227
Code: 00 e8 b2 12 28 00 9c 5b 81 e3 00 02 00 00 31 ff 48 89 de e8 80 49 20 00 48 85 db 0f 85 55 01 00 00 e8 02 4e 20 00 fb 4c 89 e0 <48> c1 e8 03 42 80 3c 38 00 0f 84 11 ff ff ff 4c 89 e7 e8 37 ce 85
RSP: 0000:ffffc9000451f428 EFLAGS: 00000287
RAX: ffffffff8f0cdb78 RBX: 0000000000000000 RCX: ffffc900199cc000
RDX: 0000000000100000 RSI: ffffffff819af7ee RDI: 0000000000000007
RBP: 0000000000000000 R08: 0000000000000007 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: ffffffff8f0cdb78
R13: ffffffff8f0cdb20 R14: ffffc9000451f4b8 R15: dffffc0000000000
 __console_flush_and_unlock kernel/printk/printk.c:3285 [inline]
 console_unlock+0xd8/0x210 kernel/printk/printk.c:3325
 vprintk_emit+0x418/0x6d0 kernel/printk/printk.c:2450
 dev_vprintk_emit drivers/base/core.c:4917 [inline]
 dev_printk_emit+0xfa/0x140 drivers/base/core.c:4928
 __dev_printk+0xf5/0x270 drivers/base/core.c:4940
 _dev_info+0xe4/0x120 drivers/base/core.c:4986
 show_string drivers/usb/core/hub.c:2369 [inline]
 show_string drivers/usb/core/hub.c:2365 [inline]
 announce_device drivers/usb/core/hub.c:2388 [inline]
 usb_new_device+0x94c/0x1a20 drivers/usb/core/hub.c:2644
 hub_port_connect drivers/usb/core/hub.c:5531 [inline]
 hub_port_connect_change drivers/usb/core/hub.c:5671 [inline]
 port_event drivers/usb/core/hub.c:5831 [inline]
 hub_event+0x2eb7/0x4fa0 drivers/usb/core/hub.c:5913
 process_one_work+0x9cf/0x1b70 kernel/workqueue.c:3238
 process_scheduled_works kernel/workqueue.c:3319 [inline]
 worker_thread+0x6c8/0xf10 kernel/workqueue.c:3400
 kthread+0x3c2/0x780 kernel/kthread.c:464
 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:153
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
rcu: rcu_preempt kthread starved for 10500 jiffies! g44017 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=1
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:R  running task     stack:28728 pid:16    tgid:16    ppid:2      task_flags:0x208040 flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5382 [inline]
 __schedule+0x116f/0x5de0 kernel/sched/core.c:6767
 __schedule_loop kernel/sched/core.c:6845 [inline]
 schedule+0xe7/0x3a0 kernel/sched/core.c:6860
 schedule_timeout+0x123/0x290 kernel/time/sleep_timeout.c:99
 rcu_gp_fqs_loop+0x1ea/0xb00 kernel/rcu/tree.c:2046
 rcu_gp_kthread+0x270/0x380 kernel/rcu/tree.c:2248
 kthread+0x3c2/0x780 kernel/kthread.c:464
 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:153
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
CPU: 1 UID: 0 PID: 5809 Comm: syz-executor Not tainted 6.15.0-rc7-syzkaller-00014-gd608703fcdd9 #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
RIP: 0010:csd_lock_wait kernel/smp.c:340 [inline]
RIP: 0010:smp_call_function_many_cond+0x4a5/0x1290 kernel/smp.c:885
Code: 89 ee e8 de 12 0c 00 85 ed 74 48 48 8b 44 24 20 49 89 c4 83 e0 07 49 c1 ec 03 48 89 c5 4d 01 f4 83 c5 03 e8 7d 17 0c 00 f3 90 <41> 0f b6 04 24 40 38 c5 7c 08 84 c0 0f 85 de 0b 00 00 8b 43 08 31
RSP: 0018:ffffc9000436f8b8 EFLAGS: 00000293
RAX: 0000000000000000 RBX: ffff8880b8441720 RCX: ffffffff81af2e99
RDX: ffff888028138000 RSI: ffffffff81af2e73 RDI: 0000000000000005
RBP: 0000000000000003 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000000 R12: ffffed10170882e5
R13: 0000000000000001 R14: dffffc0000000000 R15: ffff8880b853b040
FS:  0000555582b2f500(0000) GS:ffff888124ada000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fbfd6ae56c0 CR3: 0000000061519000 CR4: 00000000003526f0
DR0: 0100000100000000 DR1: 0000000000000006 DR2: 0000000000000005
DR3: 0000000000000011 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 on_each_cpu_cond_mask+0x40/0x90 kernel/smp.c:1052
 __flush_tlb_multi arch/x86/include/asm/paravirt.h:91 [inline]
 flush_tlb_multi arch/x86/mm/tlb.c:1291 [inline]
 flush_tlb_mm_range+0x322/0x1780 arch/x86/mm/tlb.c:1381
 dup_mmap kernel/fork.c:766 [inline]
 dup_mm kernel/fork.c:1735 [inline]
 copy_mm kernel/fork.c:1787 [inline]
 copy_process+0x7957/0x91b0 kernel/fork.c:2430
 kernel_clone+0xfc/0x960 kernel/fork.c:2845
 __do_sys_clone+0xce/0x120 kernel/fork.c:2988
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xcd/0x260 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fbfd5d851d3
Code: 1f 84 00 00 00 00 00 64 48 8b 04 25 10 00 00 00 45 31 c0 31 d2 31 f6 bf 11 00 20 01 4c 8d 90 d0 02 00 00 b8 38 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 35 89 c2 85 c0 75 2c 64 48 8b 04 25 10 00 00
RSP: 002b:00007fff95e23c08 EFLAGS: 00000246 ORIG_RAX: 0000000000000038
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007fbfd5d851d3
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000001200011
RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000000000001
R10: 0000555582b2f7d0 R11: 0000000000000246 R12: 0000000000000000
R13: 00000000000927c0 R14: 000000000007776e R15: 00007fff95e23da0
 </TASK>
watchdog: BUG: soft lockup - CPU#1 stuck for 241s! [syz-executor:5809]
Modules linked in:
irq event stamp: 8798950
hardirqs last  enabled at (8798949): [<ffffffff8b6d2fcb>] irqentry_exit+0x3b/0x90 kernel/entry/common.c:357
hardirqs last disabled at (8798950): [<ffffffff8b6d171e>] sysvec_apic_timer_interrupt+0xe/0xc0 arch/x86/kernel/apic/apic.c:1049
softirqs last  enabled at (8798938): [<ffffffff817cd24e>] softirq_handle_end kernel/softirq.c:425 [inline]
softirqs last  enabled at (8798938): [<ffffffff817cd24e>] handle_softirqs+0x5be/0x8e0 kernel/softirq.c:607
softirqs last disabled at (8798873): [<ffffffff817cd709>] __do_softirq kernel/softirq.c:613 [inline]
softirqs last disabled at (8798873): [<ffffffff817cd709>] invoke_softirq kernel/softirq.c:453 [inline]
softirqs last disabled at (8798873): [<ffffffff817cd709>] __irq_exit_rcu+0x109/0x170 kernel/softirq.c:680
CPU: 1 UID: 0 PID: 5809 Comm: syz-executor Not tainted 6.15.0-rc7-syzkaller-00014-gd608703fcdd9 #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
RIP: 0010:csd_lock_wait kernel/smp.c:340 [inline]
RIP: 0010:smp_call_function_many_cond+0x4a5/0x1290 kernel/smp.c:885
Code: 89 ee e8 de 12 0c 00 85 ed 74 48 48 8b 44 24 20 49 89 c4 83 e0 07 49 c1 ec 03 48 89 c5 4d 01 f4 83 c5 03 e8 7d 17 0c 00 f3 90 <41> 0f b6 04 24 40 38 c5 7c 08 84 c0 0f 85 de 0b 00 00 8b 43 08 31
RSP: 0018:ffffc9000436f8b8 EFLAGS: 00000293
RAX: 0000000000000000 RBX: ffff8880b8441720 RCX: ffffffff81af2e99
RDX: ffff888028138000 RSI: ffffffff81af2e73 RDI: 0000000000000005
RBP: 0000000000000003 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000000 R12: ffffed10170882e5
R13: 0000000000000001 R14: dffffc0000000000 R15: ffff8880b853b040
FS:  0000555582b2f500(0000) GS:ffff888124ada000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fbfd6ae56c0 CR3: 0000000061519000 CR4: 00000000003526f0
DR0: 0100000100000000 DR1: 0000000000000006 DR2: 0000000000000005
DR3: 0000000000000011 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 on_each_cpu_cond_mask+0x40/0x90 kernel/smp.c:1052
 __flush_tlb_multi arch/x86/include/asm/paravirt.h:91 [inline]
 flush_tlb_multi arch/x86/mm/tlb.c:1291 [inline]
 flush_tlb_mm_range+0x322/0x1780 arch/x86/mm/tlb.c:1381
 dup_mmap kernel/fork.c:766 [inline]
 dup_mm kernel/fork.c:1735 [inline]
 copy_mm kernel/fork.c:1787 [inline]
 copy_process+0x7957/0x91b0 kernel/fork.c:2430
 kernel_clone+0xfc/0x960 kernel/fork.c:2845
 __do_sys_clone+0xce/0x120 kernel/fork.c:2988
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xcd/0x260 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fbfd5d851d3
Code: 1f 84 00 00 00 00 00 64 48 8b 04 25 10 00 00 00 45 31 c0 31 d2 31 f6 bf 11 00 20 01 4c 8d 90 d0 02 00 00 b8 38 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 35 89 c2 85 c0 75 2c 64 48 8b 04 25 10 00 00
RSP: 002b:00007fff95e23c08 EFLAGS: 00000246 ORIG_RAX: 0000000000000038
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007fbfd5d851d3
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000001200011
RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000000000001
R10: 0000555582b2f7d0 R11: 0000000000000246 R12: 0000000000000000
R13: 00000000000927c0 R14: 000000000007776e R15: 00007fff95e23da0
 </TASK>
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 1219 Comm: kworker/0:3 Not tainted 6.15.0-rc7-syzkaller-00014-gd608703fcdd9 #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Workqueue: usb_hub_wq hub_event
RIP: 0010:write_comp_data+0x0/0x90 kernel/kcov.c:240
Code: 48 8b 05 cb 20 e9 11 48 8b 80 30 16 00 00 e9 87 d9 b4 09 0f 1f 80 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 <49> 89 d2 49 89 f8 49 89 f1 65 48 8b 15 97 20 e9 11 65 8b 05 a8 20
RSP: 0000:ffffc90000007c68 EFLAGS: 00000046
RAX: 0000000000000000 RBX: ffff8880581f3340 RCX: ffffffff81a86e17
RDX: 0000000000000001 RSI: 000000000000001f RDI: 0000000000000005
RBP: 0000000000000001 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000000 R14: ffff8880b8427840 R15: 0000000000000000
FS:  0000000000000000(0000) GS:ffff8881249da000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000110c2a6cdf CR3: 00000000330ac000 CR4: 00000000003526f0
DR0: 0100000100000000 DR1: 0000000000000006 DR2: 0000000000000005
DR3: 0000000000000011 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 __remove_hrtimer+0xe7/0x290 kernel/time/hrtimer.c:1122
 __run_hrtimer kernel/time/hrtimer.c:1741 [inline]
 __hrtimer_run_queues+0x4f9/0xad0 kernel/time/hrtimer.c:1825
 hrtimer_interrupt+0x397/0x8e0 kernel/time/hrtimer.c:1887
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1038 [inline]
 __sysvec_apic_timer_interrupt+0x108/0x3f0 arch/x86/kernel/apic/apic.c:1055
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1049 [inline]
 sysvec_apic_timer_interrupt+0x52/0xc0 arch/x86/kernel/apic/apic.c:1049
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:handle_softirqs+0x1dd/0x8e0 kernel/softirq.c:565
Code: 88 6c 24 26 4c 89 7c 24 18 48 c7 c7 a0 89 8b 8b e8 68 6e f0 09 65 66 c7 05 d6 91 27 12 00 00 e8 19 3c 46 00 fb bb ff ff ff ff <49> c7 c7 c0 c0 00 8e 41 0f bc dc 83 c3 01 0f 85 a4 00 00 00 e9 b1
RSP: 0000:ffffc90000007f28 EFLAGS: 00000202
RAX: 0000000000144dea RBX: 00000000ffffffff RCX: 0000000000000002
RDX: 0000000000000000 RSI: ffffffff8dbe4615 RDI: ffffffff8bf4a2e0
RBP: 0000000000000000 R08: 0000000000000001 R09: 0000000000000001
R10: ffffffff90852e17 R11: 0000000000000000 R12: 0000000000000100
R13: 000000000000000a R14: 1ffff92000000fed R15: ffffed10050db000
 __do_softirq kernel/softirq.c:613 [inline]
 invoke_softirq kernel/softirq.c:453 [inline]
 __irq_exit_rcu+0x109/0x170 kernel/softirq.c:680
 irq_exit_rcu+0x9/0x30 kernel/softirq.c:696
 instr_sysvec_call_function_single arch/x86/kernel/smp.c:266 [inline]
 sysvec_call_function_single+0xa4/0xc0 arch/x86/kernel/smp.c:266
 </IRQ>
 <TASK>
 asm_sysvec_call_function_single+0x1a/0x20 arch/x86/include/asm/idtentry.h:709
RIP: 0010:console_flush_all+0x9a2/0xc60 kernel/printk/printk.c:3227
Code: 00 e8 b2 12 28 00 9c 5b 81 e3 00 02 00 00 31 ff 48 89 de e8 80 49 20 00 48 85 db 0f 85 55 01 00 00 e8 02 4e 20 00 fb 4c 89 e0 <48> c1 e8 03 42 80 3c 38 00 0f 84 11 ff ff ff 4c 89 e7 e8 37 ce 85
RSP: 0000:ffffc9000451f428 EFLAGS: 00000287
RAX: ffffffff8f0cdb78 RBX: 0000000000000000 RCX: ffffc900199cc000
RDX: 0000000000100000 RSI: ffffffff819af7ee RDI: 0000000000000007
RBP: 0000000000000000 R08: 0000000000000007 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: ffffffff8f0cdb78
R13: ffffffff8f0cdb20 R14: ffffc9000451f4b8 R15: dffffc0000000000
 __console_flush_and_unlock kernel/printk/printk.c:3285 [inline]
 console_unlock+0xd8/0x210 kernel/printk/printk.c:3325
 vprintk_emit+0x418/0x6d0 kernel/printk/printk.c:2450
 dev_vprintk_emit drivers/base/core.c:4917 [inline]
 dev_printk_emit+0xfa/0x140 drivers/base/core.c:4928
 __dev_printk+0xf5/0x270 drivers/base/core.c:4940
 _dev_info+0xe4/0x120 drivers/base/core.c:4986
 show_string drivers/usb/core/hub.c:2369 [inline]
 show_string drivers/usb/core/hub.c:2365 [inline]
 announce_device drivers/usb/core/hub.c:2388 [inline]
 usb_new_device+0x94c/0x1a20 drivers/usb/core/hub.c:2644
 hub_port_connect drivers/usb/core/hub.c:5531 [inline]
 hub_port_connect_change drivers/usb/core/hub.c:5671 [inline]
 port_event drivers/usb/core/hub.c:5831 [inline]
 hub_event+0x2eb7/0x4fa0 drivers/usb/core/hub.c:5913
 process_one_work+0x9cf/0x1b70 kernel/workqueue.c:3238
 process_scheduled_works kernel/workqueue.c:3319 [inline]
 worker_thread+0x6c8/0xf10 kernel/workqueue.c:3400
 kthread+0x3c2/0x780 kernel/kthread.c:464
 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:153
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>