rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P15148/1:b..l P15289/1:b..l P15191/1:b..l P15143/1:b..l
rcu: 	(detected by 1, t=10502 jiffies, g=58593, q=303 ncpus=2)
task:syz.4.2260      state:R  running task     stack:23704 pid:15143 tgid:15143 ppid:5808   task_flags:0x40064c flags:0x00080001
Call Trace:
 <TASK>
 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 80 3a 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:ffffc9000bb07128 EFLAGS: 00000286
RAX: 0000000000000046 RBX: ffff88802a0dd4b0 RCX: 0000000000000001
RDX: 0000000000000000 RSI: ffffffff8daa967a RDI: ffffffff8bf2b580
RBP: ffffffff8e3c96a0 R08: 0000000000000006 R09: 0000000000000000
R10: 0000000000001000 R11: ffff88802a0dd4b0 R12: ffff88802a0dc980
R13: 0000000000000001 R14: 00000000ffffffff R15: 0000000000000000
 lookup_page_ext+0x6e/0x100 mm/page_ext.c:254
 page_ext_iter_begin include/linux/page_ext.h:132 [inline]
 __update_page_owner_free_handle.constprop.0+0xaa/0x4a0 mm/page_owner.c:284
 __reset_page_owner+0x93/0x1a0 mm/page_owner.c:321
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1433 [inline]
 free_unref_folios+0xa22/0x1610 mm/page_alloc.c:3030
 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:1954 [inline]
 iput.part.0+0x621/0x1190 fs/inode.c:2006
 iput+0x35/0x40 fs/inode.c:1969
 dentry_unlink_inode+0x29c/0x480 fs/dcache.c:467
 __dentry_kill+0x1d0/0x600 fs/dcache.c:670
 finish_dput+0x76/0x480 fs/dcache.c:879
 dput.part.0+0x451/0x570 fs/dcache.c:928
 dput+0x1f/0x30 fs/dcache.c:920
 __fput+0x51c/0xb70 fs/file_table.c:476
 task_work_run+0x150/0x240 kernel/task_work.c:233
 exit_task_work include/linux/task_work.h:40 [inline]
 do_exit+0x87f/0x2bd0 kernel/exit.c:971
 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_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:618
RIP: 0033:0x7fad65a4f6b7
RSP: 002b:00007fad66a211a0 EFLAGS: 00010206
RAX: 0000000000000000 RBX: 000000000000000b RCX: 00007fad65b8f749
RDX: 00007fad66a211c0 RSI: 00007fad66a212f0 RDI: 000000000000000b
RBP: 00007fad65c13f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000
R13: 00007fad65de6128 R14: 00007fad65de6090 R15: 00007ffd228723f8
 </TASK>
task:syz.5.2271      state:R  running task     stack:23832 pid:15191 tgid:15191 ppid:9857   task_flags:0x400640 flags:0x00080000
Call Trace:
 <TASK>
 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 ad e3 18 12 48 89 44 24 30 31 c0 66 90 65 8b 05 c9 e3 18 12 83 f8 07 0f 87 a2 02 00 00 89 c0 48 0f a3 05 52 c1 ee 0e <0f> 82 74 02 00 00 8b 35 ea f1 ee 0e 85 f6 0f 85 8d 00 00 00 48 8b
RSP: 0018:ffffc9000bdde330 EFLAGS: 00000297
RAX: 0000000000000000 RBX: ffffffff8e3c96a0 RCX: 0000000000000002
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff8e3c96a0
RBP: 0000000000000002 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000002 R11: 000000000000a975 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+0xd1/0x20b0 arch/x86/kernel/unwind_orc.c:495
 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
 __set_page_owner+0x91/0x560 mm/page_owner.c:341
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x1af/0x220 mm/page_alloc.c:1884
 prep_new_page mm/page_alloc.c:1892 [inline]
 get_page_from_freelist+0xd0b/0x31a0 mm/page_alloc.c:3945
 __alloc_frozen_pages_noprof+0x25f/0x2430 mm/page_alloc.c:5240
 alloc_pages_mpol+0x1fb/0x550 mm/mempolicy.c:2486
 folio_alloc_mpol_noprof+0x36/0x2f0 mm/mempolicy.c:2505
 shmem_alloc_folio+0x135/0x160 mm/shmem.c:1890
 shmem_alloc_and_add_folio+0x494/0xc20 mm/shmem.c:1932
 shmem_get_folio_gfp+0x67f/0x1610 mm/shmem.c:2556
 shmem_get_folio mm/shmem.c:2662 [inline]
 shmem_write_begin+0x1a4/0x3b0 mm/shmem.c:3315
 generic_perform_write+0x3c4/0x900 mm/filemap.c:4314
 shmem_file_write_iter+0x10e/0x140 mm/shmem.c:3490
 __kernel_write_iter+0x31a/0xb10 fs/read_write.c:619
 dump_emit_page fs/coredump.c:1298 [inline]
 dump_user_range+0x413/0xb70 fs/coredump.c:1372
 elf_core_dump+0x29c3/0x3c10 fs/binfmt_elf.c:2111
 coredump_write fs/coredump.c:1049 [inline]
 do_coredump fs/coredump.c:1126 [inline]
 vfs_coredump+0x2b85/0x55e0 fs/coredump.c:1200
 get_signal+0x22e1/0x26d0 kernel/signal.c:3019
 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_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:618
RIP: 0033:0x7f692284f6b7
RSP: 002b:00007f69238071a0 EFLAGS: 00010206
RAX: 0000000000000000 RBX: 000000000000000b RCX: 00007f692298f749
RDX: 00007f69238071c0 RSI: 00007f69238072f0 RDI: 000000000000000b
RBP: 00007f6922a13f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000
R13: 00007f6922be6128 R14: 00007f6922be6090 R15: 00007ffeaab57488
 </TASK>
task:syz.3.2295      state:R  running task     stack:23704 pid:15289 tgid:15289 ppid:5820   task_flags:0x400640 flags:0x00080000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5256 [inline]
 __schedule+0x1139/0x6150 kernel/sched/core.c:6863
 preempt_schedule_notrace+0x62/0xe0 kernel/sched/core.c:7140
 preempt_schedule_notrace_thunk+0x16/0x30 arch/x86/entry/thunk.S:13
 rcu_is_watching+0x8e/0xc0 kernel/rcu/tree.c:752
 rcu_read_unlock include/linux/rcupdate.h:895 [inline]
 class_rcu_destructor include/linux/rcupdate.h:1195 [inline]
 unwind_next_frame+0xa3b/0x20b0 arch/x86/kernel/unwind_orc.c:495
 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
 __set_page_owner+0x91/0x560 mm/page_owner.c:341
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x1af/0x220 mm/page_alloc.c:1884
 prep_new_page mm/page_alloc.c:1892 [inline]
 get_page_from_freelist+0xd0b/0x31a0 mm/page_alloc.c:3945
 __alloc_frozen_pages_noprof+0x25f/0x2430 mm/page_alloc.c:5240
 alloc_pages_mpol+0x1fb/0x550 mm/mempolicy.c:2486
 folio_alloc_mpol_noprof+0x36/0x2f0 mm/mempolicy.c:2505
 shmem_alloc_folio+0x135/0x160 mm/shmem.c:1890
 shmem_alloc_and_add_folio+0x494/0xc20 mm/shmem.c:1932
 shmem_get_folio_gfp+0x67f/0x1610 mm/shmem.c:2556
 shmem_get_folio mm/shmem.c:2662 [inline]
 shmem_write_begin+0x1a4/0x3b0 mm/shmem.c:3315
 generic_perform_write+0x3c4/0x900 mm/filemap.c:4314
 shmem_file_write_iter+0x10e/0x140 mm/shmem.c:3490
 __kernel_write_iter+0x31a/0xb10 fs/read_write.c:619
 dump_emit_page fs/coredump.c:1298 [inline]
 dump_user_range+0x413/0xb70 fs/coredump.c:1372
 elf_core_dump+0x29c3/0x3c10 fs/binfmt_elf.c:2111
 coredump_write fs/coredump.c:1049 [inline]
 do_coredump fs/coredump.c:1126 [inline]
 vfs_coredump+0x2b85/0x55e0 fs/coredump.c:1200
 get_signal+0x22e1/0x26d0 kernel/signal.c:3019
 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_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:618
RIP: 0033:0x7f184164f6b7
RSP: 002b:00007f18426d01a0 EFLAGS: 00010206
RAX: 0000000000000000 RBX: 000000000000000b RCX: 00007f184178f749
RDX: 00007f18426d01c0 RSI: 00007f18426d02f0 RDI: 000000000000000b
RBP: 00007f1841813f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000
R13: 00007f18419e6128 R14: 00007f18419e6090 R15: 00007ffd381da818
 </TASK>
task:syz.5.2261      state:R  running task     stack:23704 pid:15148 tgid:15148 ppid:9857   task_flags:0x40064c flags:0x00080001
Call Trace:
 <TASK>
 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_release include/trace/events/lock.h:69 [inline]
RIP: 0010:lock_release+0x1fc/0x2d0 kernel/locking/lockdep.c:5879
Code: 85 c0 74 0f 48 8b 78 08 4c 89 e2 48 89 de e8 db cb fe ff 65 ff 0d 84 e8 18 12 0f 85 39 fe ff ff e8 39 ff 91 ff e9 2f fe ff ff <e8> 6f 1b 09 00 84 c0 0f 85 42 fe ff ff 48 8d 3d c0 13 f2 0e 67 48
RSP: 0018:ffffc90005636ef0 EFLAGS: 00000297
RAX: 0000000000000000 RBX: ffffffff8e3c96a0 RCX: ffffc90005638001
RDX: 0000000000000000 RSI: ffffffff816cca34 RDI: ffffffff8e3c96a0
RBP: 0000000000000001 R08: 0000000000000001 R09: 00000000ffffffff
R10: 0000000000000002 R11: 0000000000011ab4 R12: ffffffff816cca34
R13: ffffc90005636fa8 R14: ffffc900056372d0 R15: ffffc90005636fdc
 rcu_lock_release include/linux/rcupdate.h:341 [inline]
 rcu_read_unlock include/linux/rcupdate.h:897 [inline]
 class_rcu_destructor include/linux/rcupdate.h:1195 [inline]
 unwind_next_frame+0x3f9/0x20b0 arch/x86/kernel/unwind_orc.c:495
 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:1433 [inline]
 free_unref_folios+0xa22/0x1610 mm/page_alloc.c:3030
 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:1954 [inline]
 iput.part.0+0x621/0x1190 fs/inode.c:2006
 iput+0x35/0x40 fs/inode.c:1969
 dentry_unlink_inode+0x29c/0x480 fs/dcache.c:467
 __dentry_kill+0x1d0/0x600 fs/dcache.c:670
 finish_dput+0x76/0x480 fs/dcache.c:879
 dput.part.0+0x451/0x570 fs/dcache.c:928
 dput+0x1f/0x30 fs/dcache.c:920
 __fput+0x51c/0xb70 fs/file_table.c:476
 task_work_run+0x150/0x240 kernel/task_work.c:233
 exit_task_work include/linux/task_work.h:40 [inline]
 do_exit+0x87f/0x2bd0 kernel/exit.c:971
 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_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:618
RIP: 0033:0x7f692284f6b7
RSP: 002b:00007f69237e61a0 EFLAGS: 00010206
RAX: 0000000000000000 RBX: 000000000000000b RCX: 00007f692298f749
RDX: 00007f69237e61c0 RSI: 00007f69237e62f0 RDI: 000000000000000b
RBP: 00007f6922a13f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000
R13: 00007f6922be6218 R14: 00007f6922be6180 R15: 00007ffeaab57488
 </TASK>
rcu: rcu_preempt kthread starved for 10727 jiffies! g58593 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:28472 pid:16    tgid:16    ppid:2      task_flags:0x208040 flags:0x00080000
Call Trace:
 <TASK>
 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
 </TASK>
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+0xf/0x20 arch/x86/kernel/paravirt.c:82
Code: 26 5f 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 99 11 00 fb f4 <e9> 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: 0000000003f24b25 RBX: 0000000000000000 RCX: ffffffff8b78c6d9
RDX: 0000000000000000 RSI: ffffffff8dacf709 RDI: ffffffff8bf2b580
RBP: fffffbfff1c12f68 R08: 0000000000000001 R09: ffffed101708673d
R10: ffff8880b84339eb R11: ffffffff8e098670 R12: 0000000000000000
R13: ffffffff8e097b40 R14: ffffffff9088cdd0 R15: 0000000000000000
FS:  0000000000000000(0000) GS:ffff8881248f1000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f20a980a80b CR3: 0000000055aa3000 CR4: 00000000003526f0
Call Trace:
 <TASK>
 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
 </TASK>