rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P5824/1:b..l P5831/1:b..l
rcu: (detected by 0, t=10502 jiffies, g=53049, q=447 ncpus=2)
task:syz-executor state:R running task stack:19496 pid:5831 tgid:5831 ppid:5822 task_flags:0x400140 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5256 [inline]
__schedule+0x14bc/0x5000 kernel/sched/core.c:6863
preempt_schedule_common+0x83/0xd0 kernel/sched/core.c:7047
preempt_schedule+0xae/0xc0 kernel/sched/core.c:7071
preempt_schedule_thunk+0x16/0x30 arch/x86/entry/thunk.S:12
__raw_spin_unlock include/linux/spinlock_api_smp.h:143 [inline]
_raw_spin_unlock+0x3f/0x50 kernel/locking/spinlock.c:186
spin_unlock include/linux/spinlock.h:391 [inline]
copy_pte_range mm/memory.c:1331 [inline]
copy_pmd_range+0x74f2/0x7e00 mm/memory.c:1392
copy_pud_range mm/memory.c:1429 [inline]
copy_p4d_range mm/memory.c:1453 [inline]
copy_page_range+0xb88/0x11d0 mm/memory.c:1535
dup_mmap+0xf4a/0x1b80 mm/mmap.c:1827
dup_mm kernel/fork.c:1529 [inline]
copy_mm+0x13c/0x4b0 kernel/fork.c:1581
copy_process+0x165d/0x3950 kernel/fork.c:2221
kernel_clone+0x21e/0x820 kernel/fork.c:2651
__do_sys_clone kernel/fork.c:2792 [inline]
__se_sys_clone kernel/fork.c:2776 [inline]
__x64_sys_clone+0x18b/0x1e0 kernel/fork.c:2776
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fb331d85e93
RSP: 002b:00007ffe67177db8 EFLAGS: 00000246 ORIG_RAX: 0000000000000038
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007fb331d85e93
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000001200011
RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000000000001
R10: 00005555826d37d0 R11: 0000000000000246 R12: 0000000000000000
R13: 00000000000927c0 R14: 0000000000088c18 R15: 00007ffe67177f50
task:syz-executor state:R running task stack:19272 pid:5824 tgid:5824 ppid:5820 task_flags:0x400140 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5256 [inline]
__schedule+0x14bc/0x5000 kernel/sched/core.c:6863
preempt_schedule_common+0x83/0xd0 kernel/sched/core.c:7047
preempt_schedule+0xae/0xc0 kernel/sched/core.c:7071
preempt_schedule_thunk+0x16/0x30 arch/x86/entry/thunk.S:12
__raw_spin_unlock include/linux/spinlock_api_smp.h:143 [inline]
_raw_spin_unlock+0x3f/0x50 kernel/locking/spinlock.c:186
spin_unlock include/linux/spinlock.h:391 [inline]
copy_pte_range mm/memory.c:1331 [inline]
copy_pmd_range+0x74f2/0x7e00 mm/memory.c:1392
copy_pud_range mm/memory.c:1429 [inline]
copy_p4d_range mm/memory.c:1453 [inline]
copy_page_range+0xb88/0x11d0 mm/memory.c:1535
dup_mmap+0xf4a/0x1b80 mm/mmap.c:1827
dup_mm kernel/fork.c:1529 [inline]
copy_mm+0x13c/0x4b0 kernel/fork.c:1581
copy_process+0x165d/0x3950 kernel/fork.c:2221
kernel_clone+0x21e/0x820 kernel/fork.c:2651
__do_sys_clone kernel/fork.c:2792 [inline]
__se_sys_clone kernel/fork.c:2776 [inline]
__x64_sys_clone+0x18b/0x1e0 kernel/fork.c:2776
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f4b65985e93
RSP: 002b:00007ffe4ba9dfd8 EFLAGS: 00000246 ORIG_RAX: 0000000000000038
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f4b65985e93
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000001200011
RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000000000001
R10: 00005555834e57d0 R11: 0000000000000246 R12: 0000000000000000
R13: 00000000000927c0 R14: 00000000000878ff R15: 00007ffe4ba9e170
rcu: rcu_preempt kthread starved for 10558 jiffies! g53049 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:27200 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5256 [inline]
__schedule+0x14bc/0x5000 kernel/sched/core.c:6863
__schedule_loop kernel/sched/core.c:6945 [inline]
schedule+0x165/0x360 kernel/sched/core.c:6960
schedule_timeout+0x12b/0x270 kernel/time/sleep_timeout.c:99
rcu_gp_fqs_loop+0x301/0x1540 kernel/rcu/tree.c:2083
rcu_gp_kthread+0x99/0x390 kernel/rcu/tree.c:2285
kthread+0x711/0x8a0 kernel/kthread.c:463
ret_from_fork+0x599/0xb30 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246
rcu: Stack dump where RCU GP kthread last ran:
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 11344 Comm: syz.6.1162 Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:rb_next+0x6/0xe0 lib/rbtree.c:464
Code: 5d 41 5e 41 5f 5d c3 cc cc cc cc cc 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 41 57 <41> 56 53 48 89 fb 49 bf 00 00 00 00 00 fc ff df 48 89 f8 48 c1 e8
RSP: 0018:ffffc90000a08cf8 EFLAGS: 00000006
RAX: ffffffff8b57d942 RBX: ffff8880b8728310 RCX: ffff88802e8c5b80
RDX: 0000000000010000 RSI: ffff888075b59b18 RDI: ffff888075b59b18
RBP: 1ffff1100eb6b363 R08: ffffffff8f822a77 R09: 1ffffffff1f0454e
R10: dffffc0000000000 R11: fffffbfff1f0454f R12: ffff8880b8728318
R13: dffffc0000000000 R14: ffff888075b59b18 R15: 1ffff110170e5063
FS: 00005555682af500(0000) GS:ffff888125f31000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000110c41c28a CR3: 000000007988e000 CR4: 00000000003526f0
Call Trace:
rb_erase_cached include/linux/rbtree.h:152 [inline]
timerqueue_del+0x8a/0x100 lib/timerqueue.c:57
__remove_hrtimer kernel/time/hrtimer.c:1114 [inline]
__run_hrtimer kernel/time/hrtimer.c:1757 [inline]
__hrtimer_run_queues+0x364/0xc30 kernel/time/hrtimer.c:1841
hrtimer_interrupt+0x45b/0xaa0 kernel/time/hrtimer.c:1903
local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1045 [inline]
__sysvec_apic_timer_interrupt+0x102/0x3e0 arch/x86/kernel/apic/apic.c:1062
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1056 [inline]
sysvec_apic_timer_interrupt+0xa1/0xc0 arch/x86/kernel/apic/apic.c:1056
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:__raw_spin_unlock_irq include/linux/spinlock_api_smp.h:160 [inline]
RIP: 0010:_raw_spin_unlock_irq+0x29/0x50 kernel/locking/spinlock.c:202
Code: 90 f3 0f 1e fa 53 48 89 fb 48 83 c7 18 48 8b 74 24 08 e8 5a 0f 40 f6 48 89 df e8 92 86 40 f6 e8 bd ee 6a f6 fb bf 01 00 00 00 12 76 32 f6 65 8b 05 4b 50 20 07 85 c0 74 07 5b c3 cc cc cc cc
RSP: 0018:ffffc9000caafc60 EFLAGS: 00000286
RAX: c0dfc52cbe4d6f00 RBX: ffff888027bb3780 RCX: c0dfc52cbe4d6f00
RDX: 0000000000000000 RSI: ffffffff8d7939c1 RDI: 0000000000000001
RBP: 0000000000000011 R08: ffffffff8f822a77 R09: 1ffffffff1f0454e
R10: dffffc0000000000 R11: fffffbfff1f0454f R12: 1ffff11004f76743
R13: 0000000000000000 R14: 0000000004000000 R15: ffff888027bb3a18
spin_unlock_irq include/linux/spinlock.h:401 [inline]
get_signal+0x11a7/0x1340 kernel/signal.c:3037
arch_do_signal_or_restart+0x9a/0x7a0 arch/x86/kernel/signal.c:337
__exit_to_user_mode_loop kernel/entry/common.c:41 [inline]
exit_to_user_mode_loop+0x87/0x4f0 kernel/entry/common.c:75
__exit_to_user_mode_prepare include/linux/irq-entry-common.h:226 [inline]
syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:256 [inline]
syscall_exit_to_user_mode_work include/linux/entry-common.h:159 [inline]
syscall_exit_to_user_mode include/linux/entry-common.h:194 [inline]
do_syscall_64+0x2d0/0xf80 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fe78fe4d723
Code: 00 00 00 0f 1f 40 00 41 89 fb 44 8d 56 04 4c 8d 0d f2 48 38 00 89 f0 4c 8d 05 e9 28 38 00 89 c2 81 e2 ff 1f 00 00 49 8b 0c d1 <48> 39 f1 74 28 48 85 c9 74 29 45 38 1c 10 75 23 83 c0 01 44 39 d0
RSP: 002b:00007fff01131f08 EFLAGS: 00000202
RAX: 000000008231f70e RBX: 00007fe790d15720 RCX: ffffffff8218570e
RDX: 000000000000170e RSI: ffffffff8231f70e RDI: 0000000000000019
RBP: ffffffff8231f70e R08: 00007fe7901d0000 R09: 00007fe7901d2000
R10: 000000008231f712 R11: 0000000000000019 R12: 0000000000000019
R13: 0000000000000000 R14: ffffffff8231f143 R15: 0000000000000096