rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P7426/1:b..l P5200/1:b..l P5837/1:b..l P7420/1:b..l
rcu: (detected by 1, t=10502 jiffies, g=22937, q=426 ncpus=2)
task:syz.3.345 state:R running task stack:26888 pid:7420 tgid:7415 ppid:5833 task_flags:0x40044c flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5257 [inline]
__schedule+0x14bc/0x5030 kernel/sched/core.c:6864
preempt_schedule_common+0x83/0xd0 kernel/sched/core.c:7048
preempt_schedule+0xae/0xc0 kernel/sched/core.c:7072
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]
zap_pte_range mm/memory.c:1882 [inline]
zap_pmd_range mm/memory.c:1944 [inline]
zap_pud_range mm/memory.c:1973 [inline]
zap_p4d_range mm/memory.c:1994 [inline]
unmap_page_range+0x38bc/0x4170 mm/memory.c:2015
unmap_single_vma mm/memory.c:2057 [inline]
unmap_vmas+0x399/0x580 mm/memory.c:2099
exit_mmap+0x239/0xb40 mm/mmap.c:1277
__mmput+0x118/0x430 kernel/fork.c:1173
exit_mm+0x1da/0x2c0 kernel/exit.c:581
do_exit+0x658/0x2310 kernel/exit.c:959
do_group_exit+0x21c/0x2d0 kernel/exit.c:1112
get_signal+0x1285/0x1340 kernel/signal.c:3034
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+0x2e9/0xfa0 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fcc9cb8f749
RSP: 002b:00007fcc9daaa0e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: fffffffffffffe00 RBX: 00007fcc9cde6098 RCX: 00007fcc9cb8f749
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007fcc9cde6098
RBP: 00007fcc9cde6090 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fcc9cde6128 R14: 00007ffef1547a10 R15: 00007ffef1547af8
task:syz-executor state:R running task stack:21352 pid:5837 tgid:5837 ppid:5823 task_flags:0x400140 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5257 [inline]
__schedule+0x14bc/0x5030 kernel/sched/core.c:6864
preempt_schedule_common+0x83/0xd0 kernel/sched/core.c:7048
preempt_schedule+0xae/0xc0 kernel/sched/core.c:7072
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]
fast_dput+0x233/0x430 fs/dcache.c:-1
dput+0xe8/0x1a0 fs/dcache.c:924
__fput+0x68e/0xa70 fs/file_table.c:476
fput_close_sync+0x113/0x220 fs/file_table.c:573
__do_sys_close fs/open.c:1584 [inline]
__se_sys_close fs/open.c:1569 [inline]
__x64_sys_close+0x7f/0x110 fs/open.c:1569
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fcd84b8e3aa
RSP: 002b:00007ffdd4144d90 EFLAGS: 00000293 ORIG_RAX: 0000000000000003
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00007fcd84b8e3aa
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000003
RBP: 00007ffdd4144dec R08: 0000000000000000 R09: 00007ffdd4144af7
R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000041
R13: 000000000000002c R14: 0000000000035cc0 R15: 00007ffdd4144e40
task:udevd state:R running task stack:22728 pid:5200 tgid:5200 ppid:1 task_flags:0x400140 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5257 [inline]
__schedule+0x14bc/0x5030 kernel/sched/core.c:6864
preempt_schedule_irq+0xb5/0x150 kernel/sched/core.c:7191
irqentry_exit+0x5d8/0x660 kernel/entry/common.c:216
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:lock_acquire+0x16c/0x350 kernel/locking/lockdep.c:5872
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 14 c9 d7 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:ffffc90003047758 EFLAGS: 00000206
RAX: 828d58c026ce6a00 RBX: 0000000000000000 RCX: 828d58c026ce6a00
RDX: 0000000000000001 RSI: ffffffff8d9760ce RDI: ffffffff8bbf81e0
RBP: ffffffff81745035 R08: 0000000000000000 R09: ffffffff81745035
R10: ffffc90003047918 R11: ffffffff81adcc20 R12: 0000000000000002
R13: ffffffff8df3d980 R14: 0000000000000000 R15: 0000000000000246
rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
rcu_read_lock include/linux/rcupdate.h:867 [inline]
class_rcu_constructor include/linux/rcupdate.h:1195 [inline]
unwind_next_frame+0xc2/0x2390 arch/x86/kernel/unwind_orc.c:479
arch_stack_walk+0x11c/0x150 arch/x86/kernel/stacktrace.c:25
stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122
kasan_save_stack mm/kasan/common.c:56 [inline]
kasan_save_track+0x3e/0x80 mm/kasan/common.c:77
poison_kmalloc_redzone mm/kasan/common.c:397 [inline]
__kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:414
kasan_kmalloc include/linux/kasan.h:262 [inline]
__kmalloc_cache_noprof+0x3e2/0x700 mm/slub.c:5771
kmalloc_noprof include/linux/slab.h:957 [inline]
kzalloc_noprof include/linux/slab.h:1094 [inline]
kernfs_iop_get_link+0x66/0x6c0 fs/kernfs/symlink.c:137
vfs_readlink+0x24d/0x550 fs/namei.c:6109
do_readlinkat+0x215/0x500 fs/stat.c:590
__do_sys_readlink fs/stat.c:613 [inline]
__se_sys_readlink fs/stat.c:610 [inline]
__x64_sys_readlink+0x7f/0x90 fs/stat.c:610
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fd12cd153a7
RSP: 002b:00007ffe12fd73d8 EFLAGS: 00000202 ORIG_RAX: 0000000000000059
RAX: ffffffffffffffda RBX: 00007ffe12fd7c20 RCX: 00007fd12cd153a7
RDX: 0000000000000400 RSI: 00007ffe12fd77e0 RDI: 00007ffe12fd73e0
RBP: 0000000000000200 R08: 000055aa36e3ac29 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 00007ffe12fd73e0
R13: 00007ffe12fd77e0 R14: 0000000000000001 R15: 00007ffe12fdc930
task:syz.0.346 state:R running task stack:26888 pid:7426 tgid:7422 ppid:5826 task_flags:0x40054c flags:0x00080001
Call Trace:
context_switch kernel/sched/core.c:5257 [inline]
__schedule+0x14bc/0x5030 kernel/sched/core.c:6864
preempt_schedule_irq+0xb5/0x150 kernel/sched/core.c:7191
irqentry_exit+0x5d8/0x660 kernel/entry/common.c:216
asm_sysvec_reschedule_ipi+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:lock_acquire+0x16c/0x350 kernel/locking/lockdep.c:5872
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 14 c9 d7 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:ffffc90003007158 EFLAGS: 00000206
RAX: 72f0973ccff63100 RBX: 0000000000000000 RCX: 72f0973ccff63100
RDX: 0000000000000001 RSI: ffffffff8d9760ce RDI: ffffffff8bbf81e0
RBP: ffffffff81745035 R08: 0000000000000000 R09: ffffffff81745035
R10: ffffc90003007318 R11: ffffffff81adcc20 R12: 0000000000000002
R13: ffffffff8df3d980 R14: 0000000000000000 R15: 0000000000000246
rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
rcu_read_lock include/linux/rcupdate.h:867 [inline]
class_rcu_constructor include/linux/rcupdate.h:1195 [inline]
unwind_next_frame+0xc2/0x2390 arch/x86/kernel/unwind_orc.c:479
arch_stack_walk+0x11c/0x150 arch/x86/kernel/stacktrace.c:25
stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122
kasan_save_stack+0x3e/0x60 mm/kasan/common.c:56
kasan_record_aux_stack+0xbd/0xd0 mm/kasan/generic.c:556
__call_rcu_common kernel/rcu/tree.c:3123 [inline]
call_rcu+0x157/0x9c0 kernel/rcu/tree.c:3243
destroy_inode fs/inode.c:401 [inline]
evict+0x931/0xae0 fs/inode.c:861
__dentry_kill+0x209/0x660 fs/dcache.c:670
finish_dput+0xc9/0x480 fs/dcache.c:879
__fput+0x68e/0xa70 fs/file_table.c:476
task_work_run+0x1d4/0x260 kernel/task_work.c:233
exit_task_work include/linux/task_work.h:40 [inline]
do_exit+0x6c5/0x2310 kernel/exit.c:971
do_group_exit+0x21c/0x2d0 kernel/exit.c:1112
get_signal+0x1285/0x1340 kernel/signal.c:3034
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+0x2e9/0xfa0 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fcf93b8f749
RSP: 002b:00007fcf949e90e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: fffffffffffffe00 RBX: 00007fcf93de6098 RCX: 00007fcf93b8f749
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007fcf93de6098
RBP: 00007fcf93de6090 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fcf93de6128 R14: 00007ffc83d68b70 R15: 00007ffc83d68c58
rcu: rcu_preempt kthread starved for 10581 jiffies! g22937 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:27000 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5257 [inline]
__schedule+0x14bc/0x5030 kernel/sched/core.c:6864
__schedule_loop kernel/sched/core.c:6946 [inline]
schedule+0x165/0x360 kernel/sched/core.c:6961
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 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 0 Comm: swapper/0 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:pv_native_safe_halt+0x13/0x20 arch/x86/kernel/paravirt.c:82
Code: cc cc cc cc cc cc cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 66 90 0f 00 2d 33 70 0c 00 f3 0f 1e fa fb f4 c8 f2 02 00 cc cc cc cc cc cc cc cc 90 90 90 90 90 90 90 90 90
RSP: 0018:ffffffff8dc07d80 EFLAGS: 000002c6
RAX: 69daa3a22ae55a00 RBX: ffffffff8197acb7 RCX: 69daa3a22ae55a00
RDX: 0000000000000001 RSI: ffffffff8d78f71d RDI: ffffffff8bbf81e0
RBP: ffffffff8dc07ea8 R08: ffff8880b86336db R09: 1ffff110170c66db
R10: dffffc0000000000 R11: ffffed10170c66dc R12: ffffffff8f7deb70
R13: 0000000000000000 R14: 0000000000000000 R15: 1ffffffff1b92a60
FS: 0000000000000000(0000) GS:ffff888125eba000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00005555893da5c8 CR3: 000000001dad6000 CR4: 00000000003526f0
Call Trace:
arch_safe_halt arch/x86/include/asm/paravirt.h:107 [inline]
default_idle+0x13/0x20 arch/x86/kernel/process.c:767
default_idle_call+0x73/0xb0 kernel/sched/idle.c:122
cpuidle_idle_call kernel/sched/idle.c:190 [inline]
do_idle+0x1e7/0x510 kernel/sched/idle.c:330
cpu_startup_entry+0x44/0x60 kernel/sched/idle.c:428
rest_init+0x2de/0x300 init/main.c:757
start_kernel+0x3a7/0x410 init/main.c:1206
x86_64_start_reservations+0x24/0x30 arch/x86/kernel/head64.c:310
x86_64_start_kernel+0x143/0x1c0 arch/x86/kernel/head64.c:291
common_startup_64+0x13e/0x147