rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 1-...!: (0 ticks this GP) idle=a4a4/1/0x4000000000000000 softirq=99879/99879 fqs=2
rcu: (detected by 0, t=10502 jiffies, g=99037, q=323 ncpus=2)
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 19736 Comm: syz.0.3871 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_local_irq_restore arch/x86/include/asm/irqflags.h:158 [inline]
RIP: 0010:lock_release kernel/locking/lockdep.c:5892 [inline]
RIP: 0010:lock_release+0x191/0x310 kernel/locking/lockdep.c:5875
Code: 83 99 ee 8d e8 c0 c8 a4 09 b8 ff ff ff ff 65 0f c1 05 1b 65 25 12 83 f8 01 0f 85 28 01 00 00 9c 58 f6 c4 02 0f 85 13 01 00 00 <41> f7 c6 00 02 00 00 0f 85 c0 00 00 00 48 8b 44 24 10 65 48 2b 05
RSP: 0018:ffffc90000a08d80 EFLAGS: 00000046
RAX: 0000000000000046 RBX: ffff888069d372c0 RCX: ffffc90000a08d8c
RDX: 0000000000000000 RSI: ffffffff8dee9983 RDI: ffffffff8c1c4480
RBP: ffffffff899a5ea2 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000001 R12: ffff88803e7a0000
R13: 18b3fb673a514ca4 R14: 0000000000000006 R15: 0000000000000001
FS: 00007fed006f36c0(0000) GS:ffff888124486000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f1de624f156 CR3: 00000000357dc000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
__raw_spin_unlock include/linux/spinlock_api_smp.h:167 [inline]
_raw_spin_unlock+0x16/0x50 kernel/locking/spinlock.c:190
spin_unlock include/linux/spinlock.h:390 [inline]
advance_sched+0x6a2/0xd20 net/sched/sch_taprio.c:988
__run_hrtimer kernel/time/hrtimer.c:1930 [inline]
__hrtimer_run_queues+0x470/0xa00 kernel/time/hrtimer.c:1994
hrtimer_interrupt+0x3e5/0x940 kernel/time/hrtimer.c:2113
local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1050 [inline]
__sysvec_apic_timer_interrupt+0x10b/0x460 arch/x86/kernel/apic/apic.c:1067
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1061 [inline]
sysvec_apic_timer_interrupt+0x9e/0xc0 arch/x86/kernel/apic/apic.c:1061
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:179 [inline]
RIP: 0010:_raw_spin_unlock_irqrestore+0x31/0x80 kernel/locking/spinlock.c:198
Code: f5 53 48 8b 74 24 10 48 89 fb 48 83 c7 18 e8 26 5e 58 f6 48 89 df e8 fe ad 58 f6 f7 c5 00 02 00 00 75 23 9c 58 f6 c4 02 75 37 01 00 00 00 e8 f5 79 48 f6 65 8b 05 3e 7d 7d 08 85 c0 74 16 5b
RSP: 0018:ffffc900055a7b28 EFLAGS: 00000246
RAX: 0000000000000006 RBX: ffffffff9b195118 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffffffff8df0eee6 RDI: ffffffff8c1c4480
RBP: 0000000000000286 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000800000000 R12: ffffffff9b194e80
R13: 0000000000000000 R14: ffffc900055a7c80 R15: ffffffff9b19505c
class_raw_spinlock_irqsave_destructor include/linux/spinlock.h:571 [inline]
__do_adjtimex+0x892/0xe70 kernel/time/timekeeping.c:2871
do_adjtimex+0xa0/0x370 kernel/time/timekeeping.c:2914
do_clock_adjtime kernel/time/posix-timers.c:1154 [inline]
__do_sys_clock_adjtime+0x177/0x290 kernel/time/posix-timers.c:1166
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x115/0x870 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fecff79ce59
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:00007fed006f3028 EFLAGS: 00000246 ORIG_RAX: 0000000000000131
RAX: ffffffffffffffda RBX: 00007fecffa15fa0 RCX: 00007fecff79ce59
RDX: 0000000000000000 RSI: 0000200000000340 RDI: 0000000000000000
RBP: 00007fecff832d6f R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fecffa16038 R14: 00007fecffa15fa0 R15: 00007ffedfcf7248
rcu: rcu_preempt kthread starved for 10498 jiffies! g99037 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:27992 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5388 [inline]
__schedule+0x1295/0x67a0 kernel/sched/core.c:7189
__schedule_loop kernel/sched/core.c:7268 [inline]
schedule+0xdd/0x390 kernel/sched/core.c:7283
schedule_timeout+0x127/0x280 kernel/time/sleep_timeout.c:99
rcu_gp_fqs_loop+0x1a9/0x900 kernel/rcu/tree.c:2095
rcu_gp_kthread+0x179/0x230 kernel/rcu/tree.c:2297
kthread+0x370/0x450 kernel/kthread.c:436
ret_from_fork+0x72b/0xd50 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: 14861 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+0x589/0x1700 kernel/smp.c:892
Code: b8 00 00 00 00 00 fc ff df 48 8b 54 24 08 49 89 d5 49 89 d4 49 c1 ed 03 41 83 e4 07 49 01 c5 41 83 c4 03 e8 39 84 0c 00 f3 90 <41> 0f b6 45 00 41 38 c4 7c 08 84 c0 0f 85 63 0f 00 00 8b 45 08 31
RSP: 0018:ffffc900069ff618 EFLAGS: 00000293
RAX: 0000000000000000 RBX: 0000000000000001 RCX: ffffffff81fc1d0d
RDX: ffff88803345ca80 RSI: ffffffff81fc1ce7 RDI: ffff88803345ca80
RBP: ffff8880b8540f80 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000000 R12: 0000000000000003
R13: ffffed10170a81f1 R14: 0000000000000001 R15: ffff8880b843c600
FS: 000055557a431500(0000) GS:ffff888124386000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000200000003000 CR3: 00000000ab240000 CR4: 00000000003526f0
Call Trace:
on_each_cpu_cond_mask+0x40/0x90 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+0x45f/0x16f0 arch/x86/mm/tlb.c:1451
dup_mmap+0x1307/0x21b0 mm/mmap.c:1905
dup_mm kernel/fork.c:1534 [inline]
copy_mm kernel/fork.c:1586 [inline]
copy_process+0x6c78/0x7ed0 kernel/fork.c:2264
kernel_clone+0x176/0x9e0 kernel/fork.c:2722
__do_sys_clone+0xd9/0x120 kernel/fork.c:2863
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x115/0x870 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f5a571c58d2
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:00007ffc4b9532c0 EFLAGS: 00000246 ORIG_RAX: 0000000000000038
RAX: ffffffffffffffda RBX: 00007ffc4b9532c0 RCX: 00007f5a571c58d2
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000001200011
RBP: 00007ffc4b95344c R08: 0000000000000000 R09: 0000000000000001
R10: 000055557a4317d0 R11: 0000000000000246 R12: 0000000000000001
R13: 00000000000927c0 R14: 00000000000e1ea1 R15: 00007ffc4b9534a0