rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P6598/1:b..l
rcu: (detected by 1, t=10502 jiffies, g=15629, q=865570 ncpus=2)
task:syz.4.213 state:R running task stack:26856 pid:6598 tgid:6590 ppid:5859 task_flags:0x40044c flags:0x20004004
Call Trace:
context_switch kernel/sched/core.c:5382 [inline]
__schedule+0x1b88/0x5240 kernel/sched/core.c:6767
preempt_schedule_irq+0xfe/0x1c0 kernel/sched/core.c:7090
irqentry_exit+0x5e/0x90 kernel/entry/common.c:354
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:lock_acquire+0x167/0x2f0 arch/x86/include/asm/irqflags.h:-1
Code: c7 44 24 10 00 00 00 00 9c 8f 44 24 10 f7 44 24 10 00 02 00 00 0f 85 fd 00 00 00 41 f7 c6 00 02 00 00 74 01 fb 65 48 8b 45 00 <48> 3b 44 24 38 0f 85 72 01 00 00 48 83 c4 40 5b 41 5c 41 5d 41 5e
RSP: 0018:ffffc9001c6472e8 EFLAGS: 00000206
RAX: 3d4473f81555ca00 RBX: ffffffff8ed3dfe0 RCX: 3d4473f81555ca00
RDX: 0000000000000000 RSI: ffffffff8e4fd50c RDI: ffffffff8ca1b6a0
RBP: ffffffff9368a020 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000002 R14: 0000000000000246 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]
unwind_next_frame+0xd5/0x23b0 arch/x86/kernel/unwind_orc.c:479
arch_stack_walk+0x11e/0x150 arch/x86/kernel/stacktrace.c:25
stack_trace_save+0x11a/0x1d0 kernel/stacktrace.c:122
save_stack+0xfc/0x1f0 mm/page_owner.c:156
__reset_page_owner+0x76/0x1e0 mm/page_owner.c:308
reset_page_owner include/linux/page_owner.h:25 [inline]
free_pages_prepare mm/page_alloc.c:1262 [inline]
__free_frozen_pages+0xde8/0x10a0 mm/page_alloc.c:2680
discard_slab mm/slub.c:2720 [inline]
__put_partials+0x160/0x1c0 mm/slub.c:3189
put_cpu_partial+0x17e/0x250 mm/slub.c:3264
__slab_free+0x294/0x390 mm/slub.c:4516
qlink_free mm/kasan/quarantine.c:163 [inline]
qlist_free_all+0x9a/0x140 mm/kasan/quarantine.c:179
kasan_quarantine_reduce+0x14f/0x170 mm/kasan/quarantine.c:286
__kasan_slab_alloc+0x23/0x80 mm/kasan/common.c:329
kasan_slab_alloc include/linux/kasan.h:250 [inline]
slab_post_alloc_hook mm/slub.c:4151 [inline]
slab_alloc_node mm/slub.c:4200 [inline]
kmem_cache_alloc_noprof+0x1e1/0x390 mm/slub.c:4207
taskstats_tgid_alloc kernel/taskstats.c:576 [inline]
taskstats_exit+0x360/0xa60 kernel/taskstats.c:615
do_exit+0x98f/0x27f0 kernel/exit.c:938
do_group_exit+0x207/0x2c0 kernel/exit.c:1102
get_signal+0x1696/0x1730 kernel/signal.c:3034
arch_do_signal_or_restart+0x98/0x840 arch/x86/kernel/signal.c:337
exit_to_user_mode_loop kernel/entry/common.c:111 [inline]
exit_to_user_mode_prepare include/linux/entry-common.h:329 [inline]
__syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
syscall_exit_to_user_mode+0xce/0x340 kernel/entry/common.c:218
__do_fast_syscall_32+0xc1/0x110 arch/x86/entry/syscall_32.c:309
do_fast_syscall_32+0x34/0x80 arch/x86/entry/syscall_32.c:331
entry_SYSENTER_compat_after_hwframe+0x84/0x8e
RIP: 0023:0xf7f46579
RSP: 002b:00000000f502455c EFLAGS: 00000206 ORIG_RAX: 00000000000000ac
RAX: 0000000000000000 RBX: 000000000000003e RCX: 0000000000000001
RDX: 0000000000000000 RSI: 0000000000000002 RDI: 0000000000000000
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
rcu: rcu_preempt kthread starved for 535 jiffies! g15629 f0x2 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:26520 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00004000
Call Trace:
context_switch kernel/sched/core.c:5382 [inline]
__schedule+0x1b88/0x5240 kernel/sched/core.c:6767
__schedule_loop kernel/sched/core.c:6845 [inline]
schedule+0x163/0x360 kernel/sched/core.c:6860
schedule_timeout+0x15b/0x2b0 kernel/time/sleep_timeout.c:99
rcu_gp_fqs_loop+0x2e1/0x1340 kernel/rcu/tree.c:2046
rcu_gp_kthread+0xa7/0x3b0 kernel/rcu/tree.c:2248
kthread+0x7b7/0x940 kernel/kthread.c:464
ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:153
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
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: 101 PID: 5505 Comm: dhcpcd Not tainted 6.15.0-rc1-syzkaller-00065-g3b07108ada81 #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
RIP: 0010:__debug_check_no_obj_freed lib/debugobjects.c:-1 [inline]
RIP: 0010:debug_check_no_obj_freed+0x2dd/0x590 lib/debugobjects.c:1129
Code: 00 00 49 89 c4 49 89 c5 49 c1 ed 03 48 b8 00 00 00 00 00 fc ff df 41 80 7c 05 00 00 74 08 4c 89 e7 e8 b7 41 21 fd 49 8b 04 24 <48> 89 44 24 38 49 8d 5c 24 18 48 89 d8 48 c1 e8 03 48 b9 00 00 00
RSP: 0018:ffffc90003a5f6e0 EFLAGS: 00000046
RAX: ffff888041449578 RBX: ffff88808a88d5c8 RCX: dffffc0000000000
RDX: dffffc0000000000 RSI: 0000000000000004 RDI: ffffc90003a5f5c0
RBP: ffffc90003a5f840 R08: 0000000000000003 R09: fffff5200074beb8
R10: dffffc0000000000 R11: fffff5200074beb8 R12: ffff888041449540
R13: 1ffff110082892a8 R14: ffff88808a88f050 R15: 0000000000000020
FS: 00007f30bfabc740(0000) GS:ffff888124f96000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00000000800ae018 CR3: 00000000307fe000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 000000000000000e DR6: 00000000ffff0ff0 DR7: 0000000000000400
Call Trace:
free_pages_prepare mm/page_alloc.c:1269 [inline]
__free_frozen_pages+0x581/0x10a0 mm/page_alloc.c:2680
discard_slab mm/slub.c:2720 [inline]
__put_partials+0x160/0x1c0 mm/slub.c:3189
put_cpu_partial+0x17e/0x250 mm/slub.c:3264
__slab_free+0x294/0x390 mm/slub.c:4516
qlink_free mm/kasan/quarantine.c:163 [inline]
qlist_free_all+0x9a/0x140 mm/kasan/quarantine.c:179
kasan_quarantine_reduce+0x14f/0x170 mm/kasan/quarantine.c:286
__kasan_slab_alloc+0x23/0x80 mm/kasan/common.c:329
kasan_slab_alloc include/linux/kasan.h:250 [inline]
slab_post_alloc_hook mm/slub.c:4151 [inline]
slab_alloc_node mm/slub.c:4200 [inline]
__do_kmalloc_node mm/slub.c:4330 [inline]
__kmalloc_noprof+0x238/0x4d0 mm/slub.c:4343
kmalloc_noprof include/linux/slab.h:909 [inline]
kzalloc_noprof include/linux/slab.h:1039 [inline]
tomoyo_encode2 security/tomoyo/realpath.c:45 [inline]
tomoyo_encode+0x26f/0x540 security/tomoyo/realpath.c:80
tomoyo_realpath_from_path+0x59e/0x5e0 security/tomoyo/realpath.c:283
tomoyo_get_realpath security/tomoyo/file.c:151 [inline]
tomoyo_path_number_perm+0x245/0x790 security/tomoyo/file.c:723
security_file_ioctl+0xc6/0x2a0 security/security.c:2913
__do_sys_ioctl fs/ioctl.c:900 [inline]
__se_sys_ioctl+0x46/0x160 fs/ioctl.c:892
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xf3/0x230 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f30bfb8ad49
Code: 5c c3 48 8d 44 24 08 48 89 54 24 e0 48 89 44 24 c0 48 8d 44 24 d0 48 89 44 24 c8 b8 10 00 00 00 c7 44 24 b8 10 00 00 00 0f 05 <41> 89 c0 3d 00 f0 ff ff 76 10 48 8b 15 ae 60 0d 00 f7 d8 41 83 c8
RSP: 002b:00007fff9fc4c388 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 000055ea4fe51fd0 RCX: 00007f30bfb8ad49
RDX: 00007fff9fc4c390 RSI: 0000000000008921 RDI: 0000000000000011
RBP: 0000000000000000 R08: 0000000000000008 R09: 0000000000000036
R10: 0000000000000000 R11: 0000000000000246 R12: 00007fff9fc4c390
R13: 000055ea48057f88 R14: 000055ea4fe51fd0 R15: 000055ea4fe540a0