rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 0-...!: (1 GPs behind) idle=4edc/1/0x4000000000000000 softirq=83844/83850 fqs=3
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P7213/1:b..l
rcu: (detected by 1, t=10502 jiffies, g=63313, q=679 ncpus=2)
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 14072 Comm: syz.7.2542 Not tainted 6.15.0-next-20250603-syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
RIP: 0010:arch_irqs_disabled_flags arch/x86/include/asm/irqflags.h:146 [inline]
RIP: 0010:lock_acquire+0xee/0x360 kernel/locking/lockdep.c:5872
Code: 00 00 00 00 9c 8f 44 24 30 4c 89 74 24 10 4d 89 fe 4c 8b 7c 24 30 fa 48 c7 c7 19 5f 99 8d e8 49 de c7 09 65 ff 05 e2 da fe 10 <45> 31 c9 4c 89 7c 24 08 41 f7 c7 00 02 00 00 41 0f 94 c1 4c 89 ef
RSP: 0018:ffffc90000007b60 EFLAGS: 00000002
RAX: 0000000000000000 RBX: 0000000000000000 RCX: be4941f5871df000
RDX: 0000000000000000 RSI: ffffffff8d995f19 RDI: ffffffff8be29c00
RBP: ffffffff84c7704a R08: 0000000000000001 R09: 0000000000000000
R10: ffffc90000007cb0 R11: fffff52000000f98 R12: 0000000000000000
R13: ffffffff99cc5970 R14: 0000000000000001 R15: 0000000000000046
FS: 0000000000000000(0000) GS:ffff888125c53000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b3211eff8 CR3: 000000000df38000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
__raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
_raw_spin_lock_irqsave+0xa7/0xf0 kernel/locking/spinlock.c:162
debug_object_deactivate+0x9a/0x250 lib/debugobjects.c:873
debug_hrtimer_deactivate kernel/time/hrtimer.c:450 [inline]
debug_deactivate+0x1d/0x200 kernel/time/hrtimer.c:490
__run_hrtimer kernel/time/hrtimer.c:1729 [inline]
__hrtimer_run_queues+0x2b0/0xc60 kernel/time/hrtimer.c:1825
hrtimer_interrupt+0x45b/0xaa0 kernel/time/hrtimer.c:1887
local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1039 [inline]
__sysvec_apic_timer_interrupt+0x108/0x410 arch/x86/kernel/apic/apic.c:1056
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1050 [inline]
sysvec_apic_timer_interrupt+0xa1/0xc0 arch/x86/kernel/apic/apic.c:1050
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:lock_acquire+0x175/0x360 kernel/locking/lockdep.c:5875
Code: 00 00 00 00 9c 8f 44 24 30 f7 44 24 30 00 02 00 00 0f 85 cd 00 00 00 f7 44 24 08 00 02 00 00 74 01 fb 65 48 8b 05 3b 9a fe 10 <48> 3b 44 24 58 0f 85 f2 00 00 00 48 83 c4 60 5b 41 5c 41 5d 41 5e
RSP: 0018:ffffc90004a7f4f0 EFLAGS: 00000206
RAX: be4941f5871df000 RBX: 0000000000000000 RCX: be4941f5871df000
RDX: 0000000000000000 RSI: ffffffff8db6f555 RDI: ffffffff8be29c00
RBP: ffffffff822f03a7 R08: 0000000000000000 R09: ffffffff822f03a7
R10: dffffc0000000000 R11: fffff940002ff581 R12: 0000000000000002
R13: ffffffff8e13ee80 R14: 0000000000000000 R15: 0000000000000246
rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
rcu_read_lock include/linux/rcupdate.h:841 [inline]
page_table_check_clear+0x1a4/0x700 mm/page_table_check.c:77
ptep_get_and_clear_full arch/x86/include/asm/jump_label.h:-1 [inline]
get_and_clear_full_ptes include/linux/pgtable.h:714 [inline]
zap_present_folio_ptes mm/memory.c:1505 [inline]
zap_present_ptes mm/memory.c:1590 [inline]
do_zap_pte_range mm/memory.c:1691 [inline]
zap_pte_range mm/memory.c:1735 [inline]
zap_pmd_range mm/memory.c:1827 [inline]
zap_pud_range mm/memory.c:1856 [inline]
zap_p4d_range mm/memory.c:1877 [inline]
unmap_page_range+0x3249/0x41c0 mm/memory.c:1898
unmap_single_vma mm/memory.c:1941 [inline]
unmap_vmas+0x399/0x580 mm/memory.c:1985
exit_mmap+0x248/0xb50 mm/mmap.c:1284
__mmput+0x118/0x420 kernel/fork.c:1121
exit_mm+0x1da/0x2c0 kernel/exit.c:581
do_exit+0x640/0x22e0 kernel/exit.c:943
do_group_exit+0x21c/0x2d0 kernel/exit.c:1104
__do_sys_exit_group kernel/exit.c:1115 [inline]
__se_sys_exit_group kernel/exit.c:1113 [inline]
__x64_sys_exit_group+0x3f/0x40 kernel/exit.c:1113
x64_sys_call+0x21ba/0x21c0 arch/x86/include/generated/asm/syscalls_64.h:232
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f72d238e969
Code: Unable to access opcode bytes at 0x7f72d238e93f.
RSP: 002b:00007ffda85c00a8 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f72d238e969
RDX: 0000000000000064 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007ffda85c010c R08: 00000004a85c019f R09: 00000000000927c0
R10: 0000000000000001 R11: 0000000000000246 R12: 0000000000000058
R13: 00000000000927c0 R14: 0000000000075544 R15: 00007ffda85c0160
task:udevd state:R running task stack:22408 pid:7213 tgid:7213 ppid:5204 task_flags:0x400140 flags:0x00004002
Call Trace:
context_switch kernel/sched/core.c:5396 [inline]
__schedule+0x16f5/0x4d00 kernel/sched/core.c:6785
preempt_schedule_irq+0xb5/0x150 kernel/sched/core.c:7108
irqentry_exit+0x6f/0x90 kernel/entry/common.c:307
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:kasan_check_byte include/linux/kasan.h:399 [inline]
RIP: 0010:lock_acquire+0x85/0x360 kernel/locking/lockdep.c:5845
Code: 81 f2 08 00 84 c0 75 0d f6 05 c0 e0 ec 0d 01 0f 84 d7 01 00 00 83 3d 49 21 03 0e 00 0f 84 f0 00 00 00 48 8b b4 24 90 00 00 00 <4c> 89 ef e8 13 86 85 00 83 3d 2c 21 03 0e 00 0f 84 fa 00 00 00 65
RSP: 0018:ffffc900049ef730 EFLAGS: 00000202
RAX: 0000000000000001 RBX: 0000000000000000 RCX: e9dbf7521c1adc00
RDX: 0000000000000000 RSI: ffffffff825daa98 RDI: ffffffff8be29ba0
RBP: ffffffff825daa7c R08: 0000000000000000 R09: 0000000000000000
R10: dffffc0000000000 R11: ffffed1028097e3d R12: 0000000000000002
R13: ffffffff8e13ee80 R14: 0000000000000000 R15: 0000000000000000
rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
rcu_read_lock include/linux/rcupdate.h:841 [inline]
class_rcu_constructor include/linux/rcupdate.h:1155 [inline]
kernfs_root+0x38/0x230 fs/kernfs/kernfs-internal.h:75
kernfs_root_is_locked fs/kernfs/kernfs-internal.h:109 [inline]
kernfs_rcu_name fs/kernfs/kernfs-internal.h:119 [inline]
kernfs_dop_revalidate+0x365/0x5d0 fs/kernfs/dir.c:1192
d_revalidate fs/namei.c:929 [inline]
lookup_fast+0x253/0x5b0 fs/namei.c:-1
walk_component fs/namei.c:2134 [inline]
link_path_walk+0x642/0xea0 fs/namei.c:2506
path_openat+0x28c/0x3830 fs/namei.c:4042
do_filp_open+0x1fa/0x410 fs/namei.c:4073
do_sys_openat2+0x121/0x1c0 fs/open.c:1437
do_sys_open fs/open.c:1452 [inline]
__do_sys_openat fs/open.c:1468 [inline]
__se_sys_openat fs/open.c:1463 [inline]
__x64_sys_openat+0x138/0x170 fs/open.c:1463
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fa9b36a7407
RSP: 002b:00007ffc7e690f40 EFLAGS: 00000202 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007fa9b3dc2880 RCX: 00007fa9b36a7407
RDX: 0000000000080000 RSI: 000055e29365e190 RDI: ffffffffffffff9c
RBP: 000055e29365e190 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000009
rcu: rcu_preempt kthread starved for 10496 jiffies! g63313 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:27320 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00004000
Call Trace:
context_switch kernel/sched/core.c:5396 [inline]
__schedule+0x16f5/0x4d00 kernel/sched/core.c:6785
__schedule_loop kernel/sched/core.c:6863 [inline]
schedule+0x165/0x360 kernel/sched/core.c:6878
schedule_timeout+0x12b/0x270 kernel/time/sleep_timeout.c:99
rcu_gp_fqs_loop+0x301/0x1540 kernel/rcu/tree.c:2054
rcu_gp_kthread+0x99/0x390 kernel/rcu/tree.c:2256
kthread+0x70e/0x8a0 kernel/kthread.c:464
ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148
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: 12688 Comm: syz-executor Not tainted 6.15.0-next-20250603-syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
RIP: 0010:csd_lock_wait kernel/smp.c:340 [inline]
RIP: 0010:smp_call_function_many_cond+0xf69/0x12d0 kernel/smp.c:885
Code: 00 45 8b 2f 44 89 ee 83 e6 01 31 ff e8 60 78 0b 00 41 83 e5 01 49 bd 00 00 00 00 00 fc ff df 75 07 e8 0b 74 0b 00 eb 37 f3 90 <43> 0f b6 04 2c 84 c0 75 10 41 f7 07 01 00 00 00 74 1e e8 f0 73 0b
RSP: 0018:ffffc900043bf560 EFLAGS: 00000293
RAX: ffffffff81b4ebc0 RBX: ffff8880b873cb40 RCX: ffff88807f2b9e00
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc900043bf6c0 R08: ffffffff8fa124f7 R09: 1ffffffff1f4249e
R10: dffffc0000000000 R11: fffffbfff1f4249f R12: 1ffff110170c86b5
R13: dffffc0000000000 R14: 0000000000000000 R15: ffff8880b86435a8
FS: 0000555555e79500(0000) GS:ffff888125d53000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f85040e56c0 CR3: 000000006d0ae000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
on_each_cpu_cond_mask+0x3f/0x80 kernel/smp.c:1052
__flush_tlb_multi arch/x86/include/asm/paravirt.h:91 [inline]
flush_tlb_multi arch/x86/mm/tlb.c:1361 [inline]
flush_tlb_mm_range+0x6b1/0x12c0 arch/x86/mm/tlb.c:1451
dup_mmap+0x15a0/0x1ac0 mm/mmap.c:1877
dup_mm kernel/fork.c:1477 [inline]
copy_mm+0x13c/0x4b0 kernel/fork.c:1529
copy_process+0x1706/0x3c00 kernel/fork.c:2169
kernel_clone+0x21e/0x870 kernel/fork.c:2599
__do_sys_clone kernel/fork.c:2742 [inline]
__se_sys_clone kernel/fork.c:2726 [inline]
__x64_sys_clone+0x18b/0x1e0 kernel/fork.c:2726
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f85033851d3
Code: 1f 84 00 00 00 00 00 64 48 8b 04 25 10 00 00 00 45 31 c0 31 d2 31 f6 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 35 89 c2 85 c0 75 2c 64 48 8b 04 25 10 00 00
RSP: 002b:00007ffcf8a3b428 EFLAGS: 00000246 ORIG_RAX: 0000000000000038
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f85033851d3
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000001200011
RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000000000001
R10: 0000555555e797d0 R11: 0000000000000246 R12: 0000000000000000
R13: 00000000000927c0 R14: 000000000007541a R15: 00007ffcf8a3b5c0