rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	1-...!: (1 GPs behind) idle=6a0c/1/0x4000000000000000 softirq=27932/27933 fqs=11
rcu: 	(detected by 0, t=10502 jiffies, g=29453, q=332 ncpus=2)
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 9564 Comm: syz.6.1274 Not tainted 6.14.0-syzkaller-11270-g08733088b566 #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
RIP: 0010:do_raw_spin_unlock+0x13d/0x8b0 kernel/locking/spinlock_debug.c:143
Code: 03 80 3c 28 00 74 0c 48 c7 c7 48 69 ba 8e e8 5a e6 8c 00 48 83 3d 8a b8 1a 0d 00 0f 84 9f 05 00 00 4c 89 ff e8 c4 48 91 0a 90 <48> 83 c4 28 5b 41 5c 41 5d 41 5e 41 5f 5d e9 2b 90 70 ff e8 2b e7
RSP: 0018:ffffc90000a08c00 EFLAGS: 00000046
RAX: 0000000000000001 RBX: 1ffff1100b9ff05e RCX: 0000000000000001
RDX: 0000000000000000 RSI: 0000000000000004 RDI: ffff88805cff82e8
RBP: dffffc0000000000 R08: ffff88805cff82eb R09: 1ffff1100b9ff05d
R10: dffffc0000000000 R11: ffffed100b9ff05e R12: 1ffff1100b9ff05f
R13: ffff88805cff82f8 R14: ffff88805cff82f0 R15: ffff88805cff82e8
FS:  00007f77660576c0(0000) GS:ffff8881250ac000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f7765170030 CR3: 000000006bf62000 CR4: 0000000000350ef0
Call Trace:
 <IRQ>
 __raw_spin_unlock include/linux/spinlock_api_smp.h:142 [inline]
 _raw_spin_unlock+0x1e/0x50 kernel/locking/spinlock.c:186
 spin_unlock include/linux/spinlock.h:391 [inline]
 advance_sched+0x9b4/0xca0 net/sched/sch_taprio.c:981
 __run_hrtimer kernel/time/hrtimer.c:1791 [inline]
 __hrtimer_run_queues+0x5a8/0xd40 kernel/time/hrtimer.c:1855
 hrtimer_interrupt+0x403/0xa40 kernel/time/hrtimer.c:1917
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1038 [inline]
 __sysvec_apic_timer_interrupt+0x112/0x420 arch/x86/kernel/apic/apic.c:1055
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1049 [inline]
 sysvec_apic_timer_interrupt+0xa1/0xc0 arch/x86/kernel/apic/apic.c:1049
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:console_flush_all+0x998/0xec0 arch/x86/include/asm/irqflags.h:-1
Code: 48 21 c3 0f 85 16 02 00 00 e8 94 17 21 00 4c 8b 7c 24 10 4d 85 f6 75 07 e8 85 17 21 00 eb 06 e8 7e 17 21 00 fb 48 8b 5c 24 18 <48> 8b 44 24 30 42 80 3c 28 00 74 08 48 89 df e8 d4 2f 8a 00 4c 8b
RSP: 0018:ffffc9000bfaf3c0 EFLAGS: 00000287
RAX: ffffffff81a26722 RBX: ffffffff8f59c898 RCX: 0000000000080000
RDX: ffffc9000f14b000 RSI: 0000000000005c02 RDI: 0000000000005c03
RBP: ffffc9000bfaf570 R08: ffffffff81a266f9 R09: 1ffffffff20beece
R10: dffffc0000000000 R11: fffffbfff20beecf R12: ffffffff8f59c840
R13: dffffc0000000000 R14: 0000000000000200 R15: ffffc9000bfaf5c0
 __console_flush_and_unlock kernel/printk/printk.c:3285 [inline]
 console_unlock+0x151/0x3b0 kernel/printk/printk.c:3325
 vprintk_emit+0x761/0xa40 kernel/printk/printk.c:2450
 _printk+0xd5/0x120 kernel/printk/printk.c:2475
 __ext4_msg+0x2f5/0x300 fs/ext4/super.c:985
 ext4_check_journal_data_mode+0x27b/0x420 fs/ext4/super.c:5001
 __ext4_fill_super fs/ext4/super.c:5312 [inline]
 ext4_fill_super+0x2d49/0x67c0 fs/ext4/super.c:5726
 get_tree_bdev_flags+0x492/0x5c0 fs/super.c:1636
 vfs_get_tree+0x92/0x2b0 fs/super.c:1759
 do_new_mount+0x2cf/0xb70 fs/namespace.c:3878
 do_mount fs/namespace.c:4218 [inline]
 __do_sys_mount fs/namespace.c:4429 [inline]
 __se_sys_mount+0x38c/0x400 fs/namespace.c:4406
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xf3/0x230 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f776518e90a
Code: d8 64 89 02 48 c7 c0 ff ff ff ff eb a6 e8 de 1a 00 00 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 49 89 ca b8 a5 00 00 00 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:00007f7766056e68 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007f7766056ef0 RCX: 00007f776518e90a
RDX: 0000200000000040 RSI: 00002000000001c0 RDI: 00007f7766056eb0
RBP: 0000200000000040 R08: 00007f7766056ef0 R09: 0000000000000404
R10: 0000000000000404 R11: 0000000000000246 R12: 00002000000001c0
R13: 00007f7766056eb0 R14: 0000000000000439 R15: 000000000000002c
 </TASK>
rcu: rcu_preempt kthread starved for 10480 jiffies! g29453 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->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:R  running task     stack:26976 pid:16    tgid:16    ppid:2      task_flags:0x208040 flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5382 [inline]
 __schedule+0x1b88/0x5240 kernel/sched/core.c:6767
 __schedule_loop kernel/sched/core.c:6845 [inline]
 schedule+0x163/0x360 kernel/sched/core.c:6860
 schedule_timeout+0x15b/0x2b0 kernel/time/sleep_timeout.c:99
 rcu_gp_fqs_loop+0x2e1/0x1340 kernel/rcu/tree.c:2046
 rcu_gp_kthread+0xa7/0x3b0 kernel/rcu/tree.c:2248
 kthread+0x7b9/0x940 kernel/kthread.c:464
 ret_from_fork+0x4d/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: 0 UID: 0 PID: 2955 Comm: kworker/u8:7 Not tainted 6.14.0-syzkaller-11270-g08733088b566 #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
Workqueue: netns cleanup_net
RIP: 0010:csd_lock_wait kernel/smp.c:340 [inline]
RIP: 0010:smp_call_function_single+0x466/0x1990 kernel/smp.c:679
Code: 83 e4 01 75 16 e8 9a 3d 0c 00 4d 89 fc 44 8b 7c 24 24 eb 46 e8 8b 3d 0c 00 eb 3f 4d 89 fc 44 8b 7c 24 24 f3 90 42 0f b6 04 2b <84> c0 75 10 41 f7 06 01 00 00 00 74 1e e8 68 3d 0c 00 eb e5 44 89
RSP: 0018:ffffc9000bc2f5c0 EFLAGS: 00000293
RAX: 0000000000000000 RBX: 1ffff92001785ed5 RCX: ffff888030c99e00
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc9000bc2f758 R08: ffffffff81b740fb R09: 1ffffffff20beece
R10: dffffc0000000000 R11: ffffffff816b7a60 R12: ffffffff93674020
R13: dffffc0000000000 R14: ffffc9000bc2f6a8 R15: 0000000000000000
FS:  0000000000000000(0000) GS:ffff888124fac000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b3081eff8 CR3: 000000004c5a0000 CR4: 0000000000350ef0
Call Trace:
 <TASK>
 rcu_barrier+0x327/0x530 kernel/rcu/tree.c:3826
 netdev_wait_allrefs_any net/core/dev.c:11206 [inline]
 netdev_run_todo+0x902/0xf30 net/core/dev.c:11298
 default_device_exit_batch+0x804/0x880 net/core/dev.c:12528
 ops_exit_list net/core/net_namespace.c:177 [inline]
 cleanup_net+0x8b1/0xd60 net/core/net_namespace.c:654
 process_one_work kernel/workqueue.c:3238 [inline]
 process_scheduled_works+0xac5/0x18e0 kernel/workqueue.c:3319
 worker_thread+0x870/0xd50 kernel/workqueue.c:3400
 kthread+0x7b9/0x940 kernel/kthread.c:464
 ret_from_fork+0x4d/0x80 arch/x86/kernel/process.c:153
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
watchdog: BUG: soft lockup - CPU#0 stuck for 246s! [kworker/u8:7:2955]
Modules linked in:
irq event stamp: 2882964
hardirqs last  enabled at (2882963): [<ffffffff8c2e3f13>] irqentry_exit+0x63/0x90 kernel/entry/common.c:357
hardirqs last disabled at (2882964): [<ffffffff8c2e1b0e>] sysvec_apic_timer_interrupt+0xe/0xc0 arch/x86/kernel/apic/apic.c:1049
softirqs last  enabled at (2882962): [<ffffffff8184596b>] __do_softirq kernel/softirq.c:613 [inline]
softirqs last  enabled at (2882962): [<ffffffff8184596b>] invoke_softirq kernel/softirq.c:453 [inline]
softirqs last  enabled at (2882962): [<ffffffff8184596b>] __irq_exit_rcu+0xfb/0x220 kernel/softirq.c:680
softirqs last disabled at (2882945): [<ffffffff8184596b>] __do_softirq kernel/softirq.c:613 [inline]
softirqs last disabled at (2882945): [<ffffffff8184596b>] invoke_softirq kernel/softirq.c:453 [inline]
softirqs last disabled at (2882945): [<ffffffff8184596b>] __irq_exit_rcu+0xfb/0x220 kernel/softirq.c:680
CPU: 0 UID: 0 PID: 2955 Comm: kworker/u8:7 Not tainted 6.14.0-syzkaller-11270-g08733088b566 #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
Workqueue: netns cleanup_net
RIP: 0010:csd_lock_wait kernel/smp.c:340 [inline]
RIP: 0010:smp_call_function_single+0x466/0x1990 kernel/smp.c:679
Code: 83 e4 01 75 16 e8 9a 3d 0c 00 4d 89 fc 44 8b 7c 24 24 eb 46 e8 8b 3d 0c 00 eb 3f 4d 89 fc 44 8b 7c 24 24 f3 90 42 0f b6 04 2b <84> c0 75 10 41 f7 06 01 00 00 00 74 1e e8 68 3d 0c 00 eb e5 44 89
RSP: 0018:ffffc9000bc2f5c0 EFLAGS: 00000293
RAX: 0000000000000000 RBX: 1ffff92001785ed5 RCX: ffff888030c99e00
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc9000bc2f758 R08: ffffffff81b740fb R09: 1ffffffff20beece
R10: dffffc0000000000 R11: ffffffff816b7a60 R12: ffffffff93674020
R13: dffffc0000000000 R14: ffffc9000bc2f6a8 R15: 0000000000000000
FS:  0000000000000000(0000) GS:ffff888124fac000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b3081eff8 CR3: 000000004c5a0000 CR4: 0000000000350ef0
Call Trace:
 <TASK>
 rcu_barrier+0x327/0x530 kernel/rcu/tree.c:3826
 netdev_wait_allrefs_any net/core/dev.c:11206 [inline]
 netdev_run_todo+0x902/0xf30 net/core/dev.c:11298
 default_device_exit_batch+0x804/0x880 net/core/dev.c:12528
 ops_exit_list net/core/net_namespace.c:177 [inline]
 cleanup_net+0x8b1/0xd60 net/core/net_namespace.c:654
 process_one_work kernel/workqueue.c:3238 [inline]
 process_scheduled_works+0xac5/0x18e0 kernel/workqueue.c:3319
 worker_thread+0x870/0xd50 kernel/workqueue.c:3400
 kthread+0x7b9/0x940 kernel/kthread.c:464
 ret_from_fork+0x4d/0x80 arch/x86/kernel/process.c:153
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 9564 Comm: syz.6.1274 Not tainted 6.14.0-syzkaller-11270-g08733088b566 #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
RIP: 0010:__sanitizer_cov_trace_pc+0x0/0x70 kernel/kcov.c:210
Code: 89 fb e8 23 00 00 00 48 8b 3d 34 85 b5 0c 48 89 de 5b e9 53 a0 5d 00 0f 1f 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 <f3> 0f 1e fa 48 8b 04 24 65 48 8b 0c 25 08 40 67 93 65 8b 15 78 c1
RSP: 0018:ffffc90000a08cd0 EFLAGS: 00000046
RAX: dffffc0000000000 RBX: 1ffff110170e4f22 RCX: ffff888028da0000
RDX: 0000000000010000 RSI: ffff88805cff8340 RDI: ffff88805cff8340
RBP: 1ffff1100b9ff068 R08: ffffffff8c29fe5b R09: 1ffffffff20beece
R10: dffffc0000000000 R11: fffffbfff20beecf R12: ffff8880b8727910
R13: dffffc0000000000 R14: 0000000000000000 R15: ffff88805cff8340
FS:  00007f77660576c0(0000) GS:ffff8881250ac000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f7765170030 CR3: 000000006bf62000 CR4: 0000000000350ef0
Call Trace:
 <IRQ>
 rb_link_node include/linux/rbtree.h:-1 [inline]
 rb_add_cached include/linux/rbtree.h:182 [inline]
 timerqueue_add+0x1f1/0x290 lib/timerqueue.c:40
 __run_hrtimer kernel/time/hrtimer.c:1808 [inline]
 __hrtimer_run_queues+0x6d6/0xd40 kernel/time/hrtimer.c:1855
 hrtimer_interrupt+0x403/0xa40 kernel/time/hrtimer.c:1917
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1038 [inline]
 __sysvec_apic_timer_interrupt+0x112/0x420 arch/x86/kernel/apic/apic.c:1055
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1049 [inline]
 sysvec_apic_timer_interrupt+0xa1/0xc0 arch/x86/kernel/apic/apic.c:1049
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:console_flush_all+0x998/0xec0 arch/x86/include/asm/irqflags.h:-1
Code: 48 21 c3 0f 85 16 02 00 00 e8 94 17 21 00 4c 8b 7c 24 10 4d 85 f6 75 07 e8 85 17 21 00 eb 06 e8 7e 17 21 00 fb 48 8b 5c 24 18 <48> 8b 44 24 30 42 80 3c 28 00 74 08 48 89 df e8 d4 2f 8a 00 4c 8b
RSP: 0018:ffffc9000bfaf3c0 EFLAGS: 00000287
RAX: ffffffff81a26722 RBX: ffffffff8f59c898 RCX: 0000000000080000
RDX: ffffc9000f14b000 RSI: 0000000000005c02 RDI: 0000000000005c03
RBP: ffffc9000bfaf570 R08: ffffffff81a266f9 R09: 1ffffffff20beece
R10: dffffc0000000000 R11: fffffbfff20beecf R12: ffffffff8f59c840
R13: dffffc0000000000 R14: 0000000000000200 R15: ffffc9000bfaf5c0
 __console_flush_and_unlock kernel/printk/printk.c:3285 [inline]
 console_unlock+0x151/0x3b0 kernel/printk/printk.c:3325
 vprintk_emit+0x761/0xa40 kernel/printk/printk.c:2450
 _printk+0xd5/0x120 kernel/printk/printk.c:2475
 __ext4_msg+0x2f5/0x300 fs/ext4/super.c:985
 ext4_check_journal_data_mode+0x27b/0x420 fs/ext4/super.c:5001
 __ext4_fill_super fs/ext4/super.c:5312 [inline]
 ext4_fill_super+0x2d49/0x67c0 fs/ext4/super.c:5726
 get_tree_bdev_flags+0x492/0x5c0 fs/super.c:1636
 vfs_get_tree+0x92/0x2b0 fs/super.c:1759
 do_new_mount+0x2cf/0xb70 fs/namespace.c:3878
 do_mount fs/namespace.c:4218 [inline]
 __do_sys_mount fs/namespace.c:4429 [inline]
 __se_sys_mount+0x38c/0x400 fs/namespace.c:4406
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xf3/0x230 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f776518e90a
Code: d8 64 89 02 48 c7 c0 ff ff ff ff eb a6 e8 de 1a 00 00 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 49 89 ca b8 a5 00 00 00 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:00007f7766056e68 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007f7766056ef0 RCX: 00007f776518e90a
RDX: 0000200000000040 RSI: 00002000000001c0 RDI: 00007f7766056eb0
RBP: 0000200000000040 R08: 00007f7766056ef0 R09: 0000000000000404
R10: 0000000000000404 R11: 0000000000000246 R12: 00002000000001c0
R13: 00007f7766056eb0 R14: 0000000000000439 R15: 000000000000002c
 </TASK>