rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P7863 P5809/1:b..l P7836/1:b..l P7846/1:b..l
rcu: (detected by 0, t=10502 jiffies, g=20181, q=366 ncpus=2)
task:syz.0.559 state:R running task stack:25960 pid:7846 tgid:7845 ppid:5808 task_flags:0x400140 flags:0x00080001
Call Trace:
context_switch kernel/sched/core.c:5256 [inline]
__schedule+0x1139/0x6150 kernel/sched/core.c:6863
preempt_schedule_irq+0x51/0x90 kernel/sched/core.c:7190
irqentry_exit+0x1d8/0x8c0 kernel/entry/common.c:216
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:lock_is_held_type+0x107/0x150 kernel/locking/lockdep.c:5945
Code: 00 00 b8 ff ff ff ff 65 0f c1 05 5c 10 3b 08 83 f8 01 75 2d 9c 58 f6 c4 02 75 43 48 f7 04 24 00 02 00 00 74 01 fb 48 83 c4 08 <44> 89 e8 5b 5d 41 5c 41 5d 41 5e 41 5f e9 87 2c 03 00 45 31 ed eb
RSP: 0018:ffffc9000bcf74b0 EFLAGS: 00000292
RAX: 0000000000000046 RBX: ffff88802c3fb018 RCX: 0000000000000001
RDX: 0000000000000000 RSI: ffffffff8daa563c RDI: ffffffff8bf2a580
RBP: ffffffff8e3c9620 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000000 R11: ffff88802c3faff0 R12: ffff88802c3fa4c0
R13: 0000000000000001 R14: 00000000ffffffff R15: 0000000000000001
xa_head include/linux/xarray.h:1210 [inline]
xas_start+0x477/0x790 lib/xarray.c:191
xas_load+0x22/0x5b0 lib/xarray.c:239
filemap_get_entry+0x109/0x3b0 mm/filemap.c:1895
shmem_get_folio_gfp+0x221/0x1610 mm/shmem.c:2480
shmem_fault+0x1fe/0xa00 mm/shmem.c:2757
__do_fault+0x10d/0x490 mm/memory.c:5320
do_read_fault mm/memory.c:5755 [inline]
do_fault+0xae4/0x1ad0 mm/memory.c:5889
do_pte_missing mm/memory.c:4401 [inline]
handle_pte_fault mm/memory.c:6273 [inline]
__handle_mm_fault+0x1919/0x2bb0 mm/memory.c:6411
handle_mm_fault+0x3fe/0xad0 mm/memory.c:6580
faultin_page mm/gup.c:1126 [inline]
__get_user_pages+0x54e/0x3590 mm/gup.c:1428
populate_vma_page_range+0x267/0x3f0 mm/gup.c:1860
__mm_populate+0x1d8/0x380 mm/gup.c:1963
mm_populate include/linux/mm.h:3701 [inline]
vm_mmap_pgoff+0x37f/0x470 mm/util.c:586
ksys_mmap_pgoff+0x7d/0x5c0 mm/mmap.c:604
__do_sys_mmap arch/x86/kernel/sys_x86_64.c:89 [inline]
__se_sys_mmap arch/x86/kernel/sys_x86_64.c:82 [inline]
__x64_sys_mmap+0x125/0x190 arch/x86/kernel/sys_x86_64.c:82
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xcd/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f4554b8f749
RSP: 002b:00007f4555a50038 EFLAGS: 00000246 ORIG_RAX: 0000000000000009
RAX: ffffffffffffffda RBX: 00007f4554de5fa0 RCX: 00007f4554b8f749
RDX: 0000000000000002 RSI: 0000000000b36000 RDI: 0000200000000000
RBP: 00007f4554c13f91 R08: ffffffffffffffff R09: 0000000000000000
R10: 0000000000008031 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f4554de6038 R14: 00007f4554de5fa0 R15: 00007ffdfd1a10a8
task:syz.1.556 state:R running task stack:26824 pid:7836 tgid:7836 ppid:5812 task_flags:0x40044c flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5256 [inline]
__schedule+0x1139/0x6150 kernel/sched/core.c:6863
preempt_schedule_irq+0x51/0x90 kernel/sched/core.c:7190
irqentry_exit+0x1d8/0x8c0 kernel/entry/common.c:216
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:trace_lock_acquire include/trace/events/lock.h:24 [inline]
RIP: 0010:lock_acquire+0x4e/0x330 kernel/locking/lockdep.c:5831
Code: 48 8b 05 dd 36 18 12 48 89 44 24 30 31 c0 66 90 65 8b 05 f9 36 18 12 83 f8 07 0f 87 a2 02 00 00 89 c0 48 0f a3 05 82 83 ee 0e <0f> 82 74 02 00 00 8b 35 1a b4 ee 0e 85 f6 0f 85 8d 00 00 00 48 8b
RSP: 0018:ffffc9000eb3f198 EFLAGS: 00000297
RAX: 0000000000000000 RBX: ffffffff8e3c9620 RCX: 0000000000000002
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff8e3c9620
RBP: 0000000000000002 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000002 R11: 00000000000a776d R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
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+0xd1/0x20a0 arch/x86/kernel/unwind_orc.c:479
arch_stack_walk+0x94/0x100 arch/x86/kernel/stacktrace.c:25
stack_trace_save+0x8e/0xc0 kernel/stacktrace.c:122
save_stack+0x160/0x1f0 mm/page_owner.c:165
__reset_page_owner+0x84/0x1a0 mm/page_owner.c:320
reset_page_owner include/linux/page_owner.h:25 [inline]
free_pages_prepare mm/page_alloc.c:1395 [inline]
free_unref_folios+0xa22/0x1610 mm/page_alloc.c:3000
folios_put_refs+0x4be/0x750 mm/swap.c:1002
free_pages_and_swap_cache+0x3f0/0x4a0 mm/swap_state.c:358
__tlb_batch_free_encoded_pages+0xf9/0x290 mm/mmu_gather.c:136
tlb_batch_pages_flush mm/mmu_gather.c:149 [inline]
tlb_flush_mmu_free mm/mmu_gather.c:397 [inline]
tlb_flush_mmu mm/mmu_gather.c:404 [inline]
tlb_finish_mmu+0x168/0x7c0 mm/mmu_gather.c:497
exit_mmap+0x3f9/0xb60 mm/mmap.c:1290
__mmput+0x12a/0x410 kernel/fork.c:1173
mmput+0x62/0x70 kernel/fork.c:1196
exit_mm kernel/exit.c:581 [inline]
do_exit+0x7d7/0x2bd0 kernel/exit.c:959
do_group_exit+0xd3/0x2a0 kernel/exit.c:1112
get_signal+0x2671/0x26d0 kernel/signal.c:3034
arch_do_signal_or_restart+0x8f/0x7e0 arch/x86/kernel/signal.c:337
__exit_to_user_mode_loop kernel/entry/common.c:41 [inline]
exit_to_user_mode_loop kernel/entry/common.c:75 [inline]
__exit_to_user_mode_prepare include/linux/irq-entry-common.h:226 [inline]
irqentry_exit_to_user_mode_prepare include/linux/irq-entry-common.h:270 [inline]
irqentry_exit_to_user_mode include/linux/irq-entry-common.h:339 [inline]
irqentry_exit+0x38a/0x8c0 kernel/entry/common.c:196
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0033:0x7ffac0068314
RSP: 002b:00007ffe9cf80770 EFLAGS: 00000287
RAX: 00007ffabec90f40 RBX: 00007ffabec909f0 RCX: ffffffff826a87c8
RDX: ffffffff826a87c8 RSI: ffffffff826a87c8 RDI: 00007ffabec90fd8
RBP: 00007ffabec90928 R08: 00007ffabec90c78 R09: 00007ffac03d2000
R10: 00007ffabebf9008 R11: 00000000000000ff R12: 00007ffabec90920
R13: 0000000000000017 R14: ffffffffffffffff R15: 00007ffabebf9008
task:syz-executor state:R running task stack:23656 pid:5809 tgid:5809 ppid:5806 task_flags:0x400140 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5256 [inline]
__schedule+0x1139/0x6150 kernel/sched/core.c:6863
preempt_schedule_irq+0x51/0x90 kernel/sched/core.c:7190
irqentry_exit+0x1d8/0x8c0 kernel/entry/common.c:216
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:lock_acquire+0x62/0x330 kernel/locking/lockdep.c:5872
Code: 36 18 12 83 f8 07 0f 87 a2 02 00 00 89 c0 48 0f a3 05 82 83 ee 0e 0f 82 74 02 00 00 8b 35 1a b4 ee 0e 85 f6 0f 85 8d 00 00 00 <48> 8b 44 24 30 65 48 2b 05 99 36 18 12 0f 85 ad 02 00 00 48 83 c4
RSP: 0018:ffffc900034c7558 EFLAGS: 00000206
RAX: 0000000000000046 RBX: ffffffff8e3c9620 RCX: 000000002d7dfedc
RDX: 0000000000000000 RSI: ffffffff8daa563c RDI: ffffffff8bf2a580
RBP: 0000000000000002 R08: 000000003a9e7578 R09: 0000000083a9e757
R10: 0000000000000002 R11: ffff888079188b30 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
rcu_read_lock include/linux/rcupdate.h:867 [inline]
page_ext_get+0x36/0x1a0 mm/page_ext.c:527
__reset_page_owner+0x2b/0x1a0 mm/page_owner.c:306
reset_page_owner include/linux/page_owner.h:25 [inline]
free_pages_prepare mm/page_alloc.c:1395 [inline]
free_unref_folios+0xa22/0x1610 mm/page_alloc.c:3000
folios_put_refs+0x4be/0x750 mm/swap.c:1002
folio_batch_release include/linux/pagevec.h:101 [inline]
shmem_undo_range+0x58f/0x1140 mm/shmem.c:1137
shmem_truncate_range mm/shmem.c:1249 [inline]
shmem_evict_inode+0x39e/0xbe0 mm/shmem.c:1379
evict+0x3c2/0xad0 fs/inode.c:837
iput_final fs/inode.c:1951 [inline]
iput.part.0+0x621/0x1190 fs/inode.c:2003
iput+0x35/0x40 fs/inode.c:1966
do_unlinkat+0x3d2/0x660 fs/namei.c:5443
__do_sys_unlink fs/namei.c:5474 [inline]
__se_sys_unlink fs/namei.c:5472 [inline]
__x64_sys_unlink+0xc5/0x110 fs/namei.c:5472
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xcd/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fecf998ecf7
RSP: 002b:00007fffdea9e0b8 EFLAGS: 00000206 ORIG_RAX: 0000000000000057
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007fecf998ecf7
RDX: 00007fffdea9e0e0 RSI: 00007fffdea9e170 RDI: 00007fffdea9e170
RBP: 00007fffdea9e170 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000100 R11: 0000000000000206 R12: 00007fffdea9f200
R13: 00007fecf9a13d7d R14: 00000000000337a5 R15: 00007fffdea9f240
task:syz.0.559 state:R running task stack:26824 pid:7863 tgid:7845 ppid:5808 task_flags:0x400140 flags:0x00080000
Call Trace:
rcu: rcu_preempt kthread starved for 10409 jiffies! g20181 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:28320 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5256 [inline]
__schedule+0x1139/0x6150 kernel/sched/core.c:6863
__schedule_loop kernel/sched/core.c:6945 [inline]
schedule+0xe7/0x3a0 kernel/sched/core.c:6960
schedule_timeout+0x123/0x290 kernel/time/sleep_timeout.c:99
rcu_gp_fqs_loop+0x1ea/0xaf0 kernel/rcu/tree.c:2083
rcu_gp_kthread+0x26d/0x380 kernel/rcu/tree.c:2285
kthread+0x3c5/0x780 kernel/kthread.c:463
ret_from_fork+0x983/0xb10 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:
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+0xf/0x20 arch/x86/kernel/paravirt.c:82
Code: 36 60 02 c3 cc cc cc cc 0f 1f 00 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 13 e9 12 00 fb f4 cc 35 03 00 66 2e 0f 1f 84 00 00 00 00 00 66 90 90 90 90 90 90
RSP: 0018:ffffffff8e007df8 EFLAGS: 000002c6
RAX: 0000000000c3a5dd RBX: 0000000000000000 RCX: ffffffff8b7776d9
RDX: 0000000000000000 RSI: ffffffff8dacb6cd RDI: ffffffff8bf2a580
RBP: fffffbfff1c12f68 R08: 0000000000000001 R09: ffffed101708673d
R10: ffff8880b84339eb R11: ffffffff8e098670 R12: 0000000000000000
R13: ffffffff8e097b40 R14: ffffffff90887cd0 R15: 0000000000000000
FS: 0000000000000000(0000) GS:ffff8881248fd000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000555568bea5c8 CR3: 000000007c6df000 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+0x6c/0xb0 kernel/sched/idle.c:122
cpuidle_idle_call kernel/sched/idle.c:191 [inline]
do_idle+0x38d/0x510 kernel/sched/idle.c:332
cpu_startup_entry+0x4f/0x60 kernel/sched/idle.c:430
rest_init+0x16b/0x2b0 init/main.c:757
start_kernel+0x3ef/0x4d0 init/main.c:1206
x86_64_start_reservations+0x18/0x30 arch/x86/kernel/head64.c:310
x86_64_start_kernel+0x130/0x190 arch/x86/kernel/head64.c:291
common_startup_64+0x13e/0x148