rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P12123/3:b..l
rcu: (detected by 0, t=10502 jiffies, g=43197, q=366 ncpus=2)
task:syz.4.531 state:R running task stack:25416 pid:12123 tgid:12120 ppid:5842 task_flags:0x40054c flags:0x00004006
Call Trace:
context_switch kernel/sched/core.c:5357 [inline]
__schedule+0x16f3/0x4c20 kernel/sched/core.c:6961
preempt_schedule_irq+0xb5/0x150 kernel/sched/core.c:7288
irqentry_exit+0x6f/0x90 kernel/entry/common.c:197
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:bytes_is_nonzero mm/kasan/generic.c:87 [inline]
RIP: 0010:memory_is_nonzero mm/kasan/generic.c:104 [inline]
RIP: 0010:memory_is_poisoned_n mm/kasan/generic.c:129 [inline]
RIP: 0010:memory_is_poisoned mm/kasan/generic.c:161 [inline]
RIP: 0010:check_region_inline mm/kasan/generic.c:180 [inline]
RIP: 0010:kasan_check_range+0x9f/0x2c0 mm/kasan/generic.c:189
Code: 00 fc ff df 4d 8d 34 19 4d 89 f4 4d 29 dc 49 83 fc 10 7f 29 4d 85 e4 0f 84 41 01 00 00 4c 89 cb 48 f7 d3 4c 01 fb 41 80 3b 00 <0f> 85 de 01 00 00 49 ff c3 48 ff c3 75 ee e9 21 01 00 00 44 89 dd
RSP: 0018:ffffc90005877338 EFLAGS: 00000246
RAX: 1ffffffff3211201 RBX: ffffffffffffffff RCX: ffffffff82246cdb
RDX: 0000000000000000 RSI: 0000000000000004 RDI: ffff88801c14b448
RBP: ffff88801c14b400 R08: ffff88801c14b44b R09: 1ffff11003829689
R10: dffffc0000000000 R11: ffffed1003829689 R12: 0000000000000001
R13: 0000000000000001 R14: ffffed100382968a R15: 1ffff11003829689
instrument_atomic_read include/linux/instrumented.h:68 [inline]
atomic_read include/linux/atomic/atomic-instrumented.h:32 [inline]
page_table_check_clear+0x2bb/0x700 mm/page_table_check.c:85
ptep_get_and_clear_full arch/x86/include/asm/jump_label.h:-1 [inline]
get_and_clear_full_ptes include/linux/pgtable.h:725 [inline]
zap_present_folio_ptes mm/memory.c:1499 [inline]
zap_present_ptes mm/memory.c:1581 [inline]
do_zap_pte_range mm/memory.c:1682 [inline]
zap_pte_range mm/memory.c:1726 [inline]
zap_pmd_range mm/memory.c:1818 [inline]
zap_pud_range mm/memory.c:1847 [inline]
zap_p4d_range mm/memory.c:1868 [inline]
unmap_page_range+0x2ec0/0x3c10 mm/memory.c:1889
unmap_single_vma mm/memory.c:1932 [inline]
unmap_vmas+0x399/0x580 mm/memory.c:1976
exit_mmap+0x248/0xb50 mm/mmap.c:1280
__mmput+0xcb/0x3d0 kernel/fork.c:1129
exit_mm+0x1da/0x2c0 kernel/exit.c:582
do_exit+0x648/0x2300 kernel/exit.c:949
do_group_exit+0x21c/0x2d0 kernel/exit.c:1102
get_signal+0x125e/0x1310 kernel/signal.c:3034
arch_do_signal_or_restart+0x9a/0x750 arch/x86/kernel/signal.c:337
exit_to_user_mode_loop+0x75/0x110 kernel/entry/common.c:40
exit_to_user_mode_prepare include/linux/irq-entry-common.h:225 [inline]
syscall_exit_to_user_mode_work include/linux/entry-common.h:175 [inline]
syscall_exit_to_user_mode include/linux/entry-common.h:210 [inline]
do_syscall_64+0x2bd/0x3b0 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f65e19a03ca
RSP: 002b:00007f65dfc05e68 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: fffffffffffffff4 RBX: 00007f65dfc05ef0 RCX: 00007f65e19a03ca
RDX: 00002000000000c0 RSI: 00002000000002c0 RDI: 00007f65dfc05eb0
RBP: 00002000000000c0 R08: 00007f65dfc05ef0 R09: 0000000001000884
R10: 0000000001000884 R11: 0000000000000246 R12: 00002000000002c0
R13: 00007f65dfc05eb0 R14: 0000000000005100 R15: 0000200000000400
rcu: rcu_preempt kthread timer wakeup didn't happen for 10484 jiffies! g43197 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402
rcu: Possible timer handling issue on cpu=0 timer-softirq=33869
rcu: rcu_preempt kthread starved for 10485 jiffies! g43197 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->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:I stack:27224 pid:18 tgid:18 ppid:2 task_flags:0x208040 flags:0x00004000
Call Trace:
context_switch kernel/sched/core.c:5357 [inline]
__schedule+0x16f3/0x4c20 kernel/sched/core.c:6961
__schedule_loop kernel/sched/core.c:7043 [inline]
schedule+0x165/0x360 kernel/sched/core.c:7058
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+0x70e/0x8a0 kernel/kthread.c:463
ret_from_fork+0x436/0x7d0 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: 0 UID: 0 PID: 12157 Comm: udevadm Not tainted syzkaller #0 PREEMPT_{RT,(full)}
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
RIP: 0010:csd_lock_wait kernel/smp.c:342 [inline]
RIP: 0010:smp_call_function_many_cond+0xed4/0x12d0 kernel/smp.c:877
Code: 45 8b 2c 24 44 89 ee 83 e6 01 31 ff e8 65 60 0b 00 41 83 e5 01 49 bd 00 00 00 00 00 fc ff df 75 07 e8 a0 5b 0b 00 eb 38 f3 90 <42> 0f b6 04 2b 84 c0 75 11 41 f7 04 24 01 00 00 00 74 1e e8 84 5b
RSP: 0018:ffffc9000737f580 EFLAGS: 00000293
RAX: ffffffff81b312bc RBX: 1ffff110171283b1 RCX: ffff88802b3b9dc0
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc9000737f700 R08: 0000000000000000 R09: 0000000000000000
R10: dffffc0000000000 R11: fffffbfff1e3ac27 R12: ffff8880b8941d88
R13: dffffc0000000000 R14: ffff8880b883bd00 R15: 0000000000000001
FS: 0000000000000000(0000) GS:ffff8881268bc000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fb3aa31ae9c CR3: 000000000d7a6000 CR4: 00000000003526f0
Call Trace:
on_each_cpu_cond_mask+0x3f/0x80 kernel/smp.c:1044
__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+0x6b1/0x12d0 arch/x86/mm/tlb.c:1451
tlb_flush arch/x86/include/asm/tlb.h:23 [inline]
tlb_flush_mmu_tlbonly include/asm-generic/tlb.h:490 [inline]
tlb_flush_mmu+0x1a7/0x680 mm/mmu_gather.c:403
tlb_finish_mmu+0xc3/0x1d0 mm/mmu_gather.c:497
free_ldt_pgtables+0x17b/0x320 arch/x86/kernel/ldt.c:411
arch_exit_mmap arch/x86/include/asm/mmu_context.h:234 [inline]
exit_mmap+0x17c/0xb50 mm/mmap.c:1266
__mmput+0xcb/0x3d0 kernel/fork.c:1129
exit_mm+0x1da/0x2c0 kernel/exit.c:582
do_exit+0x648/0x2300 kernel/exit.c:949
do_group_exit+0x21c/0x2d0 kernel/exit.c:1102
__do_sys_exit_group kernel/exit.c:1113 [inline]
__se_sys_exit_group kernel/exit.c:1111 [inline]
__x64_sys_exit_group+0x3f/0x40 kernel/exit.c:1111
x64_sys_call+0x21f7/0x2200 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: 0033:0x7fb3aa4166c5
Code: Unable to access opcode bytes at 0x7fb3aa41669b.
RSP: 002b:00007ffd9e7b4f88 EFLAGS: 00000202 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 00007fb3aa517fe8 RCX: 00007fb3aa4166c5
RDX: 00000000000000e7 RSI: fffffffffffffe60 RDI: 0000000000000000
RBP: 0000000000000001 R08: 00007ffd9e7b4f20 R09: 0000000000000000
R10: 00007ffd9e7b4dd0 R11: 0000000000000202 R12: 0000000000000000
R13: 0000000000000000 R14: 00007fb3aa516680 R15: 00007fb3aa518000
watchdog: BUG: soft lockup - CPU#0 stuck for 226s! [udevadm:12157]
Modules linked in:
irq event stamp: 148170
hardirqs last enabled at (148169): [] irqentry_exit+0x74/0x90 kernel/entry/common.c:200
hardirqs last disabled at (148170): [] sysvec_apic_timer_interrupt+0xe/0xc0 arch/x86/kernel/apic/apic.c:1050
softirqs last enabled at (0): [] rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
softirqs last enabled at (0): [] rcu_read_lock include/linux/rcupdate.h:841 [inline]
softirqs last enabled at (0): [] copy_process+0x979/0x3ae0 kernel/fork.c:2043
softirqs last disabled at (0): [<0000000000000000>] 0x0
CPU: 0 UID: 0 PID: 12157 Comm: udevadm Not tainted syzkaller #0 PREEMPT_{RT,(full)}
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
RIP: 0010:csd_lock_wait kernel/smp.c:342 [inline]
RIP: 0010:smp_call_function_many_cond+0xed4/0x12d0 kernel/smp.c:877
Code: 45 8b 2c 24 44 89 ee 83 e6 01 31 ff e8 65 60 0b 00 41 83 e5 01 49 bd 00 00 00 00 00 fc ff df 75 07 e8 a0 5b 0b 00 eb 38 f3 90 <42> 0f b6 04 2b 84 c0 75 11 41 f7 04 24 01 00 00 00 74 1e e8 84 5b
RSP: 0018:ffffc9000737f580 EFLAGS: 00000293
RAX: ffffffff81b312bc RBX: 1ffff110171283b1 RCX: ffff88802b3b9dc0
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc9000737f700 R08: 0000000000000000 R09: 0000000000000000
R10: dffffc0000000000 R11: fffffbfff1e3ac27 R12: ffff8880b8941d88
R13: dffffc0000000000 R14: ffff8880b883bd00 R15: 0000000000000001
FS: 0000000000000000(0000) GS:ffff8881268bc000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fb3aa31ae9c CR3: 000000000d7a6000 CR4: 00000000003526f0
Call Trace:
on_each_cpu_cond_mask+0x3f/0x80 kernel/smp.c:1044
__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+0x6b1/0x12d0 arch/x86/mm/tlb.c:1451
tlb_flush arch/x86/include/asm/tlb.h:23 [inline]
tlb_flush_mmu_tlbonly include/asm-generic/tlb.h:490 [inline]
tlb_flush_mmu+0x1a7/0x680 mm/mmu_gather.c:403
tlb_finish_mmu+0xc3/0x1d0 mm/mmu_gather.c:497
free_ldt_pgtables+0x17b/0x320 arch/x86/kernel/ldt.c:411
arch_exit_mmap arch/x86/include/asm/mmu_context.h:234 [inline]
exit_mmap+0x17c/0xb50 mm/mmap.c:1266
__mmput+0xcb/0x3d0 kernel/fork.c:1129
exit_mm+0x1da/0x2c0 kernel/exit.c:582
do_exit+0x648/0x2300 kernel/exit.c:949
do_group_exit+0x21c/0x2d0 kernel/exit.c:1102
__do_sys_exit_group kernel/exit.c:1113 [inline]
__se_sys_exit_group kernel/exit.c:1111 [inline]
__x64_sys_exit_group+0x3f/0x40 kernel/exit.c:1111
x64_sys_call+0x21f7/0x2200 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: 0033:0x7fb3aa4166c5
Code: Unable to access opcode bytes at 0x7fb3aa41669b.
RSP: 002b:00007ffd9e7b4f88 EFLAGS: 00000202 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 00007fb3aa517fe8 RCX: 00007fb3aa4166c5
RDX: 00000000000000e7 RSI: fffffffffffffe60 RDI: 0000000000000000
RBP: 0000000000000001 R08: 00007ffd9e7b4f20 R09: 0000000000000000
R10: 00007ffd9e7b4dd0 R11: 0000000000000202 R12: 0000000000000000
R13: 0000000000000000 R14: 00007fb3aa516680 R15: 00007fb3aa518000
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 12084 Comm: syz.2.528 Not tainted syzkaller #0 PREEMPT_{RT,(full)}
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
RIP: 0010:native_halt+0x18/0x30 arch/x86/include/asm/irqflags.h:55
Code: 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa e8 07 1f 4c 00 66 90 e8 00 1f 4c 00 0f 00 2d 79 e4 95 09 f4 53 61 88 09 cc f3 0f 1e fa e8 e9 1e 4c 00 f4 e9 43 61 88 09 cc
RSP: 0018:ffffc90005977318 EFLAGS: 00000046
RAX: ffffffff81724f40 RBX: 0000000000000003 RCX: 0000000000080000
RDX: ffffc9000e23b000 RSI: 000000000007ffff RDI: 0000000000080000
RBP: ffffc900059773f0 R08: 0000000000000000 R09: 0000000000000000
R10: dffffc0000000000 R11: fffff91ffffaffab R12: dffffc0000000000
R13: 0000000000000200 R14: 0000000000000003 R15: 1ffff92000b2ee68
FS: 00007f43ef4a66c0(0000) GS:ffff8881269bc000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f0e68bc9000 CR3: 0000000068c7e000 CR4: 00000000003526f0
Call Trace:
halt arch/x86/include/asm/paravirt.h:112 [inline]
kvm_wait+0x188/0x290 arch/x86/kernel/kvm.c:1058
pv_wait arch/x86/include/asm/paravirt.h:569 [inline]
pv_wait_head_or_lock kernel/locking/qspinlock_paravirt.h:466 [inline]
__pv_queued_spin_lock_slowpath+0x7bf/0xb60 kernel/locking/qspinlock.c:325
pv_queued_spin_lock_slowpath arch/x86/include/asm/paravirt.h:557 [inline]
queued_spin_lock_slowpath+0x43/0x50 arch/x86/include/asm/qspinlock.h:51
queued_spin_lock include/asm-generic/qspinlock.h:114 [inline]
do_raw_spin_lock+0x21f/0x290 kernel/locking/spinlock_debug.c:116
__raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:111 [inline]
_raw_spin_lock_irqsave+0xb3/0xf0 kernel/locking/spinlock.c:162
rtlock_slowlock kernel/locking/rtmutex.c:1894 [inline]
rtlock_lock kernel/locking/spinlock_rt.c:43 [inline]
__rt_spin_lock kernel/locking/spinlock_rt.c:49 [inline]
rt_spin_lock+0x144/0x2c0 kernel/locking/spinlock_rt.c:57
spin_lock include/linux/spinlock_rt.h:44 [inline]
do_slab_free mm/slub.c:4662 [inline]
___cache_free+0x9b/0x200 mm/slub.c:4753
qlink_free mm/kasan/quarantine.c:163 [inline]
qlist_free_all+0x97/0x140 mm/kasan/quarantine.c:179
kasan_quarantine_remove_cache+0x16a/0x190 mm/kasan/quarantine.c:378
kmem_cache_destroy+0x6e/0x160 mm/slab_common.c:521
bio_put_slab block/bio.c:155 [inline]
bioset_exit+0x583/0x690 block/bio.c:1764
bch2_fs_io_read_exit+0x67/0x80 fs/bcachefs/io_read.c:1518
__bch2_fs_free fs/bcachefs/super.c:607 [inline]
bch2_fs_release+0x24c/0x830 fs/bcachefs/super.c:667
kobject_cleanup lib/kobject.c:689 [inline]
kobject_release lib/kobject.c:720 [inline]
kref_put include/linux/kref.h:65 [inline]
kobject_put+0x22b/0x480 lib/kobject.c:737
bch2_fs_get_tree+0xb6e/0x1520 fs/bcachefs/fs.c:2604
vfs_get_tree+0x8f/0x2b0 fs/super.c:1815
do_new_mount+0x2a2/0x9e0 fs/namespace.c:3808
do_mount fs/namespace.c:4136 [inline]
__do_sys_mount fs/namespace.c:4347 [inline]
__se_sys_mount+0x317/0x410 fs/namespace.c:4324
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: 0033:0x7f43f12403ca
Code: d8 64 89 02 48 c7 c0 ff ff ff ff eb a6 e8 de 1a 00 00 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 49 89 ca b8 a5 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f43ef4a5e68 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007f43ef4a5ef0 RCX: 00007f43f12403ca
RDX: 0000200000000080 RSI: 0000200000000000 RDI: 00007f43ef4a5eb0
RBP: 0000200000000080 R08: 00007f43ef4a5ef0 R09: 0000000000800015
R10: 0000000000800015 R11: 0000000000000246 R12: 0000200000000000
R13: 00007f43ef4a5eb0 R14: 00000000000059b3 R15: 0000200000000600