rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P17541/1:b..l
rcu: (detected by 0, t=10502 jiffies, g=220905, q=647 ncpus=1)
task:syz.1.2055 state:R running task stack:26624 pid:17541 tgid:17540 ppid:13763 task_flags:0x40054c flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5521 [inline]
__schedule+0x1b57/0x5bc0 kernel/sched/core.c:7272
preempt_schedule_common+0x7f/0xd0 kernel/sched/core.c:7451
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+0x41/0x50 kernel/locking/spinlock.c:213
spin_unlock include/linux/spinlock.h:401 [inline]
zap_pte_range mm/memory.c:2095 [inline]
zap_pmd_range mm/memory.c:2151 [inline]
zap_pud_range mm/memory.c:2179 [inline]
zap_p4d_range mm/memory.c:2200 [inline]
__zap_vma_range+0x40e1/0x4f80 mm/memory.c:2240
unmap_vmas+0x390/0x550 mm/memory.c:2309
exit_mmap+0x293/0x9f0 mm/mmap.c:1315
__mmput+0x118/0x420 kernel/fork.c:1193
exit_mm+0x221/0x2d0 kernel/exit.c:614
do_exit+0x6cd/0x2360 kernel/exit.c:996
do_group_exit+0x22d/0x2f0 kernel/exit.c:1151
get_signal+0x121b/0x12c0 kernel/signal.c:3039
arch_do_signal_or_restart+0xbb/0x860 arch/x86/kernel/signal.c:337
__exit_to_user_mode_loop kernel/entry/common.c:66 [inline]
exit_to_user_mode_loop+0x10e/0x770 kernel/entry/common.c:101
__exit_to_user_mode_prepare include/linux/irq-entry-common.h:207 [inline]
syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:230 [inline]
syscall_exit_to_user_mode include/linux/entry-common.h:336 [inline]
do_syscall_64+0x328/0x520 arch/x86/entry/syscall_64.c:89
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f70ee59e0d9
RSP: 002b:00007f70ef3800e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: fffffffffffffe00 RBX: 00007f70ee825fa8 RCX: 00007f70ee59e0d9
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f70ee825fa8
RBP: 00007f70ee825fa0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f70ee826038 R14: 00007fff825a3cf0 R15: 00007fff825a3dd8
rcu: rcu_preempt kthread starved for 10309 jiffies! g220905 f0x0 RCU_GP_DOING_FQS(6) ->state=R ->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:27496 pid:18 tgid:18 ppid:2 task_flags:0x208040 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5521 [inline]
__schedule+0x1b57/0x5bc0 kernel/sched/core.c:7272
preempt_schedule_irq+0x4b/0x90 kernel/sched/core.c:7594
irqentry_exit_to_kernel_mode include/linux/irq-entry-common.h:539 [inline]
irqentry_exit+0x14f/0x910 kernel/entry/common.c:167
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:674
RIP: 0010:force_qs_rnp kernel/rcu/tree.c:2773 [inline]
RIP: 0010:rcu_gp_fqs kernel/rcu/tree.c:-1 [inline]
RIP: 0010:rcu_gp_fqs_loop+0x637/0x11f0 kernel/rcu/tree.c:2144
Code: 28 0d 00 8b 05 7a ac cc 0e ff c8 48 63 d8 83 fb 02 0f 83 72 0a 00 00 48 8d 1c dd c0 2b d6 8e 48 89 d8 48 c1 e8 03 80 3c 30 00 <74> 12 48 89 df e8 2f ea 89 00 48 be 00 00 00 00 00 fc ff df 4c 8b
RSP: 0018:ffffc90000177be0 EFLAGS: 00000246
RAX: 1ffffffff1dac578 RBX: ffffffff8ed62bc0 RCX: ffffffff81adc650
RDX: 0000000000000001 RSI: dffffc0000000000 RDI: 00000000ffffffff
RBP: ffffc90000177d30 R08: ffffffff907a477f R09: 1ffffffff20f48ef
R10: dffffc0000000000 R11: fffffbfff20f48f0 R12: ffff88801c6ae400
R13: 1ffff9200002efac R14: ffffc90000177ca8 R15: 0000000000000000
rcu_gp_kthread+0x9e/0x2b0 kernel/rcu/tree.c:2330
kthread+0x38b/0x480 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: 17490 Comm: syz.2.2050 Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
RIP: 0010:lock_is_held_type+0x106/0x150 kernel/locking/lockdep.c:5987
Code: 1a 00 00 b8 ff ff ff ff 65 0f c1 05 dc fd b0 07 83 f8 01 75 25 9c 58 a9 00 02 00 00 75 39 41 f7 c4 00 02 00 00 74 01 fb 89 d8 <5b> 41 5c 41 5d 41 5e 41 5f 5d e9 9b 03 03 00 cc 90 0f 0b 90 48 c7
RSP: 0018:ffffc9000558faf0 EFLAGS: 00000206
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000046
RDX: 0000000000000000 RSI: ffffffff8e6ff314 RDI: ffffffff8c6d8d80
RBP: 00000000ffffffff R08: ffffc9000558f9cf R09: 1ffff92000ab1f39
R10: dffffc0000000000 R11: fffff52000ab1f3a R12: 0000000000000246
R13: ffff888033569f40 R14: ffffffff8ed5cac0 R15: 0000000000000000
FS: 00007f7be5df66c0(0000) GS:ffff888124cd8000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f95038e5730 CR3: 0000000045f6e000 CR4: 00000000003526f0
DR0: 0000000000000009 DR1: 0000000000000009 DR2: 0000000000000003
DR3: 0000000000000008 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Call Trace:
lock_is_held include/linux/lockdep.h:249 [inline]
__might_resched+0x37/0x4c0 kernel/sched/core.c:9198
__might_fault+0x76/0x130 mm/memory.c:7480
_inline_copy_to_user include/linux/uaccess.h:197 [inline]
_copy_to_user+0x2c/0xb0 lib/usercopy.c:24
copy_to_user include/linux/uaccess.h:230 [inline]
copy_siginfo_to_user+0x22/0xc0 kernel/signal.c:3506
x64_setup_rt_frame+0x764/0xc50 arch/x86/kernel/signal_64.c:194
setup_rt_frame arch/x86/kernel/signal.c:250 [inline]
handle_signal arch/x86/kernel/signal.c:294 [inline]
arch_do_signal_or_restart+0x456/0x860 arch/x86/kernel/signal.c:339
__exit_to_user_mode_loop kernel/entry/common.c:66 [inline]
exit_to_user_mode_loop+0x10e/0x770 kernel/entry/common.c:101
__exit_to_user_mode_prepare include/linux/irq-entry-common.h:207 [inline]
syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:230 [inline]
syscall_exit_to_user_mode include/linux/entry-common.h:336 [inline]
do_syscall_64+0x328/0x520 arch/x86/entry/syscall_64.c:89
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f7be7b9e0d7
Code: 83 c8 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
RSP: 002b:00007f7be5df60e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: 00000000000000ca RBX: 00007f7be7e25fa8 RCX: 00007f7be7b9e0d9
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f7be7e25fa8
RBP: 00007f7be7e25fa0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f7be7e26038 R14: 00007fffc21a3d70 R15: 00007fffc21a3e58