rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 0-...!: (1 GPs behind) idle=d67c/1/0x4000000000000000 softirq=57390/57391 fqs=2
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P7567/1:b..l
rcu: (detected by 1, t=10502 jiffies, g=59921, q=195 ncpus=2)
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 12818 Comm: syz.0.1632 Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/05/2026
RIP: 0010:task_irq_context kernel/locking/lockdep.c:4698 [inline]
RIP: 0010:__lock_acquire+0x165/0x1ec0 kernel/locking/lockdep.c:5190
Code: 1c 08 0f b7 43 20 4c 89 7b 10 66 25 00 e0 09 d0 31 d2 66 89 43 20 48 8b 84 24 b0 00 00 00 48 89 43 08 48 8b 04 24 48 89 43 18 <65> 8b 05 e4 a1 a4 12 41 8b 8c 24 8c 0b 00 00 85 c0 0f 95 c2 31 c0
RSP: 0018:ffffc90000007c98 EFLAGS: 00000046
RAX: 0000000000000000 RBX: ffff888033233128 RCX: 0000000000000000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff8edec060
RBP: 0000000000000007 R08: 0000000000000000 R09: 0000000000000001
R10: 0000000000000000 R11: 0000000000000001 R12: ffff888033232580
R13: 0000000000000002 R14: 0000000000000000 R15: ffffffff8edec060
FS: 00007f6b52b856c0(0000) GS:ffff888123b6b000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f9593b556c8 CR3: 000000004bcd1000 CR4: 00000000003526f0
Call Trace:
lock_acquire kernel/locking/lockdep.c:5886 [inline]
lock_acquire+0x1b9/0x370 kernel/locking/lockdep.c:5843
rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
rcu_read_lock include/linux/rcupdate.h:849 [inline]
advance_sched+0x718/0xd20 net/sched/sch_taprio.c:993
__run_hrtimer kernel/time/hrtimer.c:2067 [inline]
__hrtimer_run_queues+0x462/0x9c0 kernel/time/hrtimer.c:2124
hrtimer_interrupt+0x441/0xaa0 kernel/time/hrtimer.c:2243
local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1051 [inline]
__sysvec_apic_timer_interrupt+0x109/0x470 arch/x86/kernel/apic/apic.c:1068
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1062 [inline]
sysvec_apic_timer_interrupt+0x9e/0xc0 arch/x86/kernel/apic/apic.c:1062
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:674
RIP: 0010:__raw_spin_unlock_irq_enable include/linux/spinlock_api_smp.h:229 [inline]
RIP: 0010:_raw_spin_unlock_irq_enable+0x4c/0x90 kernel/locking/spinlock.c:237
Code: 00 ff ff 65 48 0f c1 05 1a a6 ba 08 48 2d 00 00 01 00 a9 00 00 ff 00 75 11 65 f6 05 06 e8 ba 08 02 75 22 9c 58 f6 c4 02 75 35 01 00 00 00 e8 ba c8 05 f6 65 48 83 3d e9 a5 ba 08 00 74 15 5b
RSP: 0018:ffffc90005d07d90 EFLAGS: 00000246
RAX: 0000000000000002 RBX: ffffffff9b990438 RCX: 0000000000000000
RDX: 0000000000000001 RSI: ffffffff8e3ec481 RDI: ffffffff8c61fb80
RBP: ffffc90005d07e40 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000000 R12: 1ffff92000ba0fb7
R13: 000000000ca5703d R14: 000000000ca5703d R15: 0000000000000000
class_raw_spinlock_irqsave_destructor include/linux/spinlock.h:594 [inline]
do_settimeofday64+0x31c/0x4c0 kernel/time/timekeeping.c:1711
do_sys_settimeofday64+0x1dc/0x260 kernel/time/time.c:204
__do_sys_clock_settime kernel/time/posix-timers.c:1139 [inline]
__se_sys_clock_settime kernel/time/posix-timers.c:1123 [inline]
__x64_sys_clock_settime+0x1c1/0x2a0 kernel/time/posix-timers.c:1123
do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
do_syscall_64+0x123/0x790 arch/x86/entry/syscall_64.c:84
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f6b51d9e0d9
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:00007f6b52b85028 EFLAGS: 00000246 ORIG_RAX: 00000000000000e3
RAX: ffffffffffffffda RBX: 00007f6b52025fa0 RCX: 00007f6b51d9e0d9
RDX: 0000000000000000 RSI: 0000200000000240 RDI: 0000000000000000
RBP: 00007f6b51e35024 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f6b52026038 R14: 00007f6b52025fa0 R15: 00007ffd18cbe738
task:syz-executor state:R running task stack:22760 pid:7567 tgid:7567 ppid:7559 task_flags:0x400140 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5520 [inline]
__schedule+0x1259/0x6920 kernel/sched/core.c:7270
preempt_schedule_common+0x3c/0xb0 kernel/sched/core.c:7449
preempt_schedule_thunk+0x16/0x40 arch/x86/entry/thunk.S:12
__raw_spin_unlock include/linux/spinlock_api_smp.h:201 [inline]
_raw_spin_unlock+0x3e/0x50 kernel/locking/spinlock.c:213
spin_unlock include/linux/spinlock.h:401 [inline]
copy_pte_range mm/memory.c:1367 [inline]
copy_pmd_range mm/memory.c:1428 [inline]
copy_pud_range mm/memory.c:1465 [inline]
copy_p4d_range mm/memory.c:1489 [inline]
copy_page_range+0x1c2b/0x5820 mm/memory.c:1575
dup_mmap+0x1230/0x2370 mm/mmap.c:1819
dup_mm kernel/fork.c:1543 [inline]
copy_mm kernel/fork.c:1595 [inline]
copy_process+0x4820/0x8370 kernel/fork.c:2307
kernel_clone+0x176/0x9d0 kernel/fork.c:2766
__do_sys_clone+0xd9/0x120 kernel/fork.c:2908
do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
do_syscall_64+0x123/0x790 arch/x86/entry/syscall_64.c:84
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f9592dc6b52
RSP: 002b:00007ffe9049a7f0 EFLAGS: 00000246 ORIG_RAX: 0000000000000038
RAX: ffffffffffffffda RBX: 00007ffe9049a7f0 RCX: 00007f9592dc6b52
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000001200011
RBP: 00007ffe9049a97c R08: 0000000000000000 R09: 0000000000000001
R10: 000055556510f7d0 R11: 0000000000000246 R12: 0000000000000001
R13: 00000000000927c0 R14: 00000000000b7817 R15: 00007ffe9049a9d0
rcu: rcu_preempt kthread starved for 10498 jiffies! g59921 f0x0 RCU_GP_WAIT_FQS(5) ->state=R ->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:28840 pid:17 tgid:17 ppid:2 task_flags:0x208040 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5520 [inline]
__schedule+0x1259/0x6920 kernel/sched/core.c:7270
__schedule_loop kernel/sched/core.c:7347 [inline]
schedule+0xdd/0x2c0 kernel/sched/core.c:7362
schedule_timeout+0x127/0x280 kernel/time/sleep_timeout.c:99
rcu_gp_fqs_loop+0x1a9/0x8f0 kernel/rcu/tree.c:2122
rcu_gp_kthread+0x17a/0x220 kernel/rcu/tree.c:2330
kthread+0x373/0x450 kernel/kthread.c:436
ret_from_fork+0x730/0xd60 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: 1 UID: 0 PID: 12820 Comm: syz.0.1632 Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/05/2026
RIP: 0010:csd_lock_wait kernel/smp.c:363 [inline]
RIP: 0010:csd_lock kernel/smp.c:396 [inline]
RIP: 0010:smp_call_function_many_cond+0x577/0x18c0 kernel/smp.c:944
Code: e4 74 50 48 b8 00 00 00 00 00 fc ff df 48 89 ea 49 89 ec 48 c1 ea 03 41 83 e4 07 4c 8d 2c 02 41 83 c4 03 e8 5b c0 0c 00 f3 90 <41> 0f b6 45 00 41 38 c4 7c 08 84 c0 0f 85 51 11 00 00 44 8b 73 08
RSP: 0018:ffffc90005fef0b8 EFLAGS: 00000246
RAX: 0000000000080000 RBX: ffff8880b8443d60 RCX: ffffc9000ef5a000
RDX: 0000000000080000 RSI: ffffffff81ff1595 RDI: ffff888036852580
RBP: ffff8880b8443d68 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000000 R12: 0000000000000003
R13: ffffed10170887ad R14: 0000000000000001 R15: 0000000000000000
FS: 00007f6b4fff66c0(0000) GS:ffff888123c6b000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f1bab63eff8 CR3: 000000004bcd1000 CR4: 00000000003526f0
Call Trace:
__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+0x3c9/0x1350 arch/x86/mm/tlb.c:1435
tlb_flush arch/x86/include/asm/tlb.h:23 [inline]
tlb_flush_mmu_tlbonly include/asm-generic/tlb.h:509 [inline]
tlb_flush_mmu_tlbonly include/asm-generic/tlb.h:499 [inline]
tlb_flush_mmu mm/mmu_gather.c:423 [inline]
tlb_finish_mmu+0x3fe/0x810 mm/mmu_gather.c:549
unmap_region+0x2d9/0x3b0 mm/vma.c:506
vms_clear_ptes mm/vma.c:1348 [inline]
vms_clean_up_area mm/vma.c:1360 [inline]
__mmap_setup mm/vma.c:2533 [inline]
__mmap_region+0x1bab/0x30b0 mm/vma.c:2818
mmap_region+0x3db/0x6d0 mm/vma.c:2921
do_mmap+0x12c7/0x1c30 mm/mmap.c:573
vm_mmap_pgoff+0x28d/0x470 mm/util.c:581
ksys_mmap_pgoff+0x285/0x610 mm/mmap.c:619
__do_sys_mmap arch/x86/kernel/sys_x86_64.c:89 [inline]
__se_sys_mmap arch/x86/kernel/sys_x86_64.c:82 [inline]
__x64_sys_mmap+0x125/0x190 arch/x86/kernel/sys_x86_64.c:82
do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
do_syscall_64+0x123/0x790 arch/x86/entry/syscall_64.c:84
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f6b51d9e0d9
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:00007f6b4fff6028 EFLAGS: 00000246 ORIG_RAX: 0000000000000009
RAX: ffffffffffffffda RBX: 00007f6b52026090 RCX: 00007f6b51d9e0d9
RDX: 0000000002000009 RSI: 0000000000400000 RDI: 0000200000000000
RBP: 00007f6b51e35024 R08: ffffffffffffffff R09: 0000000000000000
R10: 000200000006c832 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f6b52026128 R14: 00007f6b52026090 R15: 00007ffd18cbe738