rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 1-...!: (1 GPs behind) idle=c75c/1/0x4000000000000000 softirq=71305/71306 fqs=3
rcu: (detected by 0, t=10502 jiffies, g=50361, q=888 ncpus=2)
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 12467 Comm: syz.8.1455 Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
RIP: 0010:arch_atomic_read arch/x86/include/asm/atomic.h:23 [inline]
RIP: 0010:raw_atomic_read include/linux/atomic/atomic-arch-fallback.h:457 [inline]
RIP: 0010:atomic_read include/linux/atomic/atomic-instrumented.h:33 [inline]
RIP: 0010:queued_spin_is_locked include/asm-generic/qspinlock.h:57 [inline]
RIP: 0010:debug_spin_unlock kernel/locking/spinlock_debug.c:101 [inline]
RIP: 0010:do_raw_spin_unlock+0x50/0x210 kernel/locking/spinlock_debug.c:141
Code: 42 0f b6 04 20 84 c0 0f 85 57 01 00 00 41 81 3e ad 4e ad de 0f 85 c6 00 00 00 48 89 df be 04 00 00 00 e8 63 aa 8e 00 48 89 d8 <48> c1 e8 03 42 0f b6 04 20 84 c0 0f 85 47 01 00 00 83 3b 00 0f 84
RSP: 0018:ffffc90000a08d88 EFLAGS: 00000056
RAX: ffffffff9a6efcb0 RBX: ffffffff9a6efcb0 RCX: ffffffff81a2577d
RDX: 0000000000000000 RSI: 0000000000000004 RDI: ffffffff9a6efcb0
RBP: ffff888054746300 R08: ffffffff9a6efcb3 R09: 1ffffffff34ddf96
R10: dffffc0000000000 R11: fffffbfff34ddf97 R12: dffffc0000000000
R13: ffff8880b8728410 R14: ffffffff9a6efcb4 R15: dffffc0000000000
FS: 00007fb9e06246c0(0000) GS:ffff88812538d000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f37d8148000 CR3: 000000005f4fc000 CR4: 0000000000350ef0
Call Trace:
__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:177 [inline]
_raw_spin_unlock_irqrestore+0x23/0x80 kernel/locking/spinlock.c:198
debug_hrtimer_deactivate kernel/time/hrtimer.c:490 [inline]
__run_hrtimer kernel/time/hrtimer.c:1898 [inline]
__hrtimer_run_queues+0x23a/0xa20 kernel/time/hrtimer.c:1994
hrtimer_interrupt+0x44b/0x950 kernel/time/hrtimer.c:2113
local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1050 [inline]
__sysvec_apic_timer_interrupt+0x102/0x430 arch/x86/kernel/apic/apic.c:1067
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1061 [inline]
sysvec_apic_timer_interrupt+0xa1/0xc0 arch/x86/kernel/apic/apic.c:1061
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:console_flush_one_record arch/x86/include/asm/irqflags.h:-1 [inline]
RIP: 0010:console_flush_all+0x801/0xb20 kernel/printk/printk.c:3343
Code: ff ff e8 62 ec 20 00 90 0f 0b 90 e9 85 fc ff ff e8 54 ec 20 00 e8 9f ef 03 0a 48 85 db 74 c0 e8 45 ec 20 00 fb 48 8b 5c 24 08 <48> 8b 44 24 20 42 80 3c 20 00 4c 8b 74 24 18 74 08 4c 89 f7 e8 c6
RSP: 0018:ffffc9000545f120 EFLAGS: 00000246
RAX: ffffffff81a4d58b RBX: ffffc9000545f280 RCX: 0000000000080000
RDX: ffffc90006402000 RSI: 000000000007ffff RDI: 0000000000080000
RBP: ffffc9000545f230 R08: ffffffff9030b6f7 R09: 1ffffffff20616de
R10: dffffc0000000000 R11: fffffbfff20616df R12: dffffc0000000000
R13: 0000000000000001 R14: 0000000000000000 R15: ffffffff8f21a020
__console_flush_and_unlock kernel/printk/printk.c:3373 [inline]
console_unlock+0xd1/0x1c0 kernel/printk/printk.c:3413
vprintk_emit+0x485/0x560 kernel/printk/printk.c:2479
_printk+0xdd/0x130 kernel/printk/printk.c:2504
__ext4_warning+0x21b/0x230 fs/ext4/super.c:1026
ext4_evict_inode+0x9d3/0x10e0 fs/ext4/inode.c:-1
evict+0x61e/0xb10 fs/inode.c:841
ext4_orphan_cleanup+0xc38/0x1470 fs/ext4/orphan.c:472
__ext4_fill_super fs/ext4/super.c:5701 [inline]
ext4_fill_super+0x5a19/0x6330 fs/ext4/super.c:5824
get_tree_bdev_flags+0x431/0x4f0 fs/super.c:1694
vfs_get_tree+0x92/0x2a0 fs/super.c:1754
fc_mount fs/namespace.c:1193 [inline]
do_new_mount_fc fs/namespace.c:3758 [inline]
do_new_mount+0x341/0xd30 fs/namespace.c:3834
do_mount fs/namespace.c:4167 [inline]
__do_sys_mount fs/namespace.c:4383 [inline]
__se_sys_mount+0x31d/0x420 fs/namespace.c:4360
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x15f/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fb9df79e0ca
Code: 48 c7 c2 e8 ff ff ff f7 d8 64 89 02 b8 ff ff ff ff c3 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 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fb9e0623e58 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007fb9e0623ee0 RCX: 00007fb9df79e0ca
RDX: 00002000000004c0 RSI: 00002000000001c0 RDI: 00007fb9e0623ea0
RBP: 00002000000004c0 R08: 00007fb9e0623ee0 R09: 000000000080078b
R10: 000000000080078b R11: 0000000000000246 R12: 00002000000001c0
R13: 00007fb9e0623ea0 R14: 000000000000046f R15: 00002000000000c0
rcu: rcu_preempt kthread starved for 10485 jiffies! g50361 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:26784 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5388 [inline]
__schedule+0x1821/0x5740 kernel/sched/core.c:7189
__schedule_loop kernel/sched/core.c:7268 [inline]
schedule+0x164/0x360 kernel/sched/core.c:7283
schedule_timeout+0x158/0x2c0 kernel/time/sleep_timeout.c:99
rcu_gp_fqs_loop+0x312/0x11d0 kernel/rcu/tree.c:2095
rcu_gp_kthread+0x9e/0x2b0 kernel/rcu/tree.c:2297
kthread+0x388/0x470 kernel/kthread.c:436
ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
rcu: Stack dump where RCU GP kthread last ran:
CPU: 0 UID: 0 PID: 8345 Comm: syz-executor Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
RIP: 0010:csd_lock_wait kernel/smp.c:342 [inline]
RIP: 0010:smp_call_function_many_cond+0xfcf/0x13d0 kernel/smp.c:892
Code: 79 45 8b 2e 44 89 ee 83 e6 01 31 ff e8 da 07 0c 00 41 83 e5 01 49 bd 00 00 00 00 00 fc ff df 75 07 e8 85 03 0c 00 eb 37 f3 90 <43> 0f b6 04 2c 84 c0 75 10 41 f7 06 01 00 00 00 74 1e e8 6a 03 0c
RSP: 0018:ffffc90004fd7560 EFLAGS: 00000293
RAX: ffffffff81b9be66 RBX: ffff8880b863c148 RCX: ffff8880274d8000
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc90004fd7688 R08: ffffffff9030b6f7 R09: 1ffffffff20616de
R10: dffffc0000000000 R11: fffffbfff20616df R12: 1ffff110170e8169
R13: dffffc0000000000 R14: ffff8880b8740b48 R15: 0000000000000001
FS: 000055557fb43500(0000) GS:ffff88812528d000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f8ddac40ff8 CR3: 000000008398b000 CR4: 0000000000350ef0
Call Trace:
on_each_cpu_cond_mask+0x3f/0x80 kernel/smp.c:1057
__flush_tlb_multi arch/x86/include/asm/paravirt.h:46 [inline]
flush_tlb_multi arch/x86/mm/tlb.c:1361 [inline]
flush_tlb_mm_range+0x5c3/0x10b0 arch/x86/mm/tlb.c:1451
dup_mmap+0x17a2/0x1d90 mm/mmap.c:1905
dup_mm kernel/fork.c:1534 [inline]
copy_mm+0x13b/0x4a0 kernel/fork.c:1586
copy_process+0x1f1c/0x4440 kernel/fork.c:2264
kernel_clone+0x284/0x8f0 kernel/fork.c:2721
__do_sys_clone kernel/fork.c:2862 [inline]
__se_sys_clone kernel/fork.c:2846 [inline]
__x64_sys_clone+0x1b6/0x230 kernel/fork.c:2846
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x15f/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7faa001c58d2
Code: 89 e7 e8 71 8b f7 ff 45 31 c0 31 d2 31 f6 64 48 8b 04 25 10 00 00 00 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 66 89 c5 85 c0 75 3b 64 48 8b 04 25 10 00 00
RSP: 002b:00007ffcba320a30 EFLAGS: 00000246 ORIG_RAX: 0000000000000038
RAX: ffffffffffffffda RBX: 00007ffcba320a30 RCX: 00007faa001c58d2
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000001200011
RBP: 00007ffcba320bbc R08: 0000000000000000 R09: 0000000000000001
R10: 000055557fb437d0 R11: 0000000000000246 R12: 0000000000000001
R13: 00000000000927c0 R14: 00000000000adc5e R15: 00007ffcba320c10
watchdog: BUG: soft lockup - CPU#0 stuck for 246s! [syz-executor:8345]
Modules linked in:
irq event stamp: 1861312
hardirqs last enabled at (1861311): [] irqentry_exit_to_kernel_mode_after_preempt include/linux/irq-entry-common.h:515 [inline]
hardirqs last enabled at (1861311): [] irqentry_exit_to_kernel_mode include/linux/irq-entry-common.h:550 [inline]
hardirqs last enabled at (1861311): [] irqentry_exit+0x218/0x760 kernel/entry/common.c:164
hardirqs last disabled at (1861312): [] sysvec_apic_timer_interrupt+0xe/0xc0 arch/x86/kernel/apic/apic.c:1061
softirqs last enabled at (1861308): [] __do_softirq kernel/softirq.c:656 [inline]
softirqs last enabled at (1861308): [] invoke_softirq kernel/softirq.c:496 [inline]
softirqs last enabled at (1861308): [] __irq_exit_rcu+0xca/0x220 kernel/softirq.c:735
softirqs last disabled at (1861281): [] __do_softirq kernel/softirq.c:656 [inline]
softirqs last disabled at (1861281): [] invoke_softirq kernel/softirq.c:496 [inline]
softirqs last disabled at (1861281): [] __irq_exit_rcu+0xca/0x220 kernel/softirq.c:735
CPU: 0 UID: 0 PID: 8345 Comm: syz-executor Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
RIP: 0010:csd_lock_wait kernel/smp.c:342 [inline]
RIP: 0010:smp_call_function_many_cond+0xfd4/0x13d0 kernel/smp.c:892
Code: 89 ee 83 e6 01 31 ff e8 da 07 0c 00 41 83 e5 01 49 bd 00 00 00 00 00 fc ff df 75 07 e8 85 03 0c 00 eb 37 f3 90 43 0f b6 04 2c <84> c0 75 10 41 f7 06 01 00 00 00 74 1e e8 6a 03 0c 00 eb e5 44 89
RSP: 0018:ffffc90004fd7560 EFLAGS: 00000293
RAX: 0000000000000000 RBX: ffff8880b863c148 RCX: ffff8880274d8000
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc90004fd7688 R08: ffffffff9030b6f7 R09: 1ffffffff20616de
R10: dffffc0000000000 R11: fffffbfff20616df R12: 1ffff110170e8169
R13: dffffc0000000000 R14: ffff8880b8740b48 R15: 0000000000000001
FS: 000055557fb43500(0000) GS:ffff88812528d000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f8ddac40ff8 CR3: 000000008398b000 CR4: 0000000000350ef0
Call Trace:
on_each_cpu_cond_mask+0x3f/0x80 kernel/smp.c:1057
__flush_tlb_multi arch/x86/include/asm/paravirt.h:46 [inline]
flush_tlb_multi arch/x86/mm/tlb.c:1361 [inline]
flush_tlb_mm_range+0x5c3/0x10b0 arch/x86/mm/tlb.c:1451
dup_mmap+0x17a2/0x1d90 mm/mmap.c:1905
dup_mm kernel/fork.c:1534 [inline]
copy_mm+0x13b/0x4a0 kernel/fork.c:1586
copy_process+0x1f1c/0x4440 kernel/fork.c:2264
kernel_clone+0x284/0x8f0 kernel/fork.c:2721
__do_sys_clone kernel/fork.c:2862 [inline]
__se_sys_clone kernel/fork.c:2846 [inline]
__x64_sys_clone+0x1b6/0x230 kernel/fork.c:2846
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x15f/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7faa001c58d2
Code: 89 e7 e8 71 8b f7 ff 45 31 c0 31 d2 31 f6 64 48 8b 04 25 10 00 00 00 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 66 89 c5 85 c0 75 3b 64 48 8b 04 25 10 00 00
RSP: 002b:00007ffcba320a30 EFLAGS: 00000246 ORIG_RAX: 0000000000000038
RAX: ffffffffffffffda RBX: 00007ffcba320a30 RCX: 00007faa001c58d2
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000001200011
RBP: 00007ffcba320bbc R08: 0000000000000000 R09: 0000000000000001
R10: 000055557fb437d0 R11: 0000000000000246 R12: 0000000000000001
R13: 00000000000927c0 R14: 00000000000adc5e R15: 00007ffcba320c10
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 12467 Comm: syz.8.1455 Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
RIP: 0010:debug_lockdep_rcu_enabled+0x0/0x40 kernel/rcu/update.c:319
Code: 48 8d 3d d3 50 8b 04 48 c7 c6 3a 05 f9 8d 67 48 0f b9 3a 90 eb ca cc cc cc cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 0f 1e fa 31 c0 83 3d 63 ed 87 04 00 74 1d 83 3d 1a 1f 88 04 00
RSP: 0018:ffffc90000a08d08 EFLAGS: 00000046
RAX: 5674fcbe7a001900 RBX: ffff88807bcd0036 RCX: 0000000000000001
RDX: 0000000000000001 RSI: 0000000000000004 RDI: ffffc90000a08c80
RBP: ffff888054746300 R08: 0000000000000003 R09: 0000000000000004
R10: dffffc0000000000 R11: fffff52000141190 R12: ffff888028d5e7b8
R13: ffff888054746000 R14: ffff888054746300 R15: dffffc0000000000
FS: 00007fb9e06246c0(0000) GS:ffff88812538d000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f37d8148000 CR3: 000000005f4fc000 CR4: 0000000000350ef0
Call Trace:
advance_sched+0xb9/0xc20 net/sched/sch_taprio.c:931
__run_hrtimer kernel/time/hrtimer.c:1930 [inline]
__hrtimer_run_queues+0x3c0/0xa20 kernel/time/hrtimer.c:1994
hrtimer_interrupt+0x44b/0x950 kernel/time/hrtimer.c:2113
local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1050 [inline]
__sysvec_apic_timer_interrupt+0x102/0x430 arch/x86/kernel/apic/apic.c:1067
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1061 [inline]
sysvec_apic_timer_interrupt+0xa1/0xc0 arch/x86/kernel/apic/apic.c:1061
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:console_flush_one_record arch/x86/include/asm/irqflags.h:-1 [inline]
RIP: 0010:console_flush_all+0x801/0xb20 kernel/printk/printk.c:3343
Code: ff ff e8 62 ec 20 00 90 0f 0b 90 e9 85 fc ff ff e8 54 ec 20 00 e8 9f ef 03 0a 48 85 db 74 c0 e8 45 ec 20 00 fb 48 8b 5c 24 08 <48> 8b 44 24 20 42 80 3c 20 00 4c 8b 74 24 18 74 08 4c 89 f7 e8 c6
RSP: 0018:ffffc9000545f120 EFLAGS: 00000246
RAX: ffffffff81a4d58b RBX: ffffc9000545f280 RCX: 0000000000080000
RDX: ffffc90006402000 RSI: 000000000007ffff RDI: 0000000000080000
RBP: ffffc9000545f230 R08: ffffffff9030b6f7 R09: 1ffffffff20616de
R10: dffffc0000000000 R11: fffffbfff20616df R12: dffffc0000000000
R13: 0000000000000001 R14: 0000000000000000 R15: ffffffff8f21a020
__console_flush_and_unlock kernel/printk/printk.c:3373 [inline]
console_unlock+0xd1/0x1c0 kernel/printk/printk.c:3413
vprintk_emit+0x485/0x560 kernel/printk/printk.c:2479
_printk+0xdd/0x130 kernel/printk/printk.c:2504
__ext4_warning+0x21b/0x230 fs/ext4/super.c:1026
ext4_evict_inode+0x9d3/0x10e0 fs/ext4/inode.c:-1
evict+0x61e/0xb10 fs/inode.c:841
ext4_orphan_cleanup+0xc38/0x1470 fs/ext4/orphan.c:472
__ext4_fill_super fs/ext4/super.c:5701 [inline]
ext4_fill_super+0x5a19/0x6330 fs/ext4/super.c:5824
get_tree_bdev_flags+0x431/0x4f0 fs/super.c:1694
vfs_get_tree+0x92/0x2a0 fs/super.c:1754
fc_mount fs/namespace.c:1193 [inline]
do_new_mount_fc fs/namespace.c:3758 [inline]
do_new_mount+0x341/0xd30 fs/namespace.c:3834
do_mount fs/namespace.c:4167 [inline]
__do_sys_mount fs/namespace.c:4383 [inline]
__se_sys_mount+0x31d/0x420 fs/namespace.c:4360
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x15f/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fb9df79e0ca
Code: 48 c7 c2 e8 ff ff ff f7 d8 64 89 02 b8 ff ff ff ff c3 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 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fb9e0623e58 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007fb9e0623ee0 RCX: 00007fb9df79e0ca
RDX: 00002000000004c0 RSI: 00002000000001c0 RDI: 00007fb9e0623ea0
RBP: 00002000000004c0 R08: 00007fb9e0623ee0 R09: 000000000080078b
R10: 000000000080078b R11: 0000000000000246 R12: 00002000000001c0
R13: 00007fb9e0623ea0 R14: 000000000000046f R15: 00002000000000c0