rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P29168/1:b..l P29032/1:b..l
rcu: (detected by 0, t=10502 jiffies, g=163993, q=586 ncpus=2)
task:syz-executor state:R running task stack:24312 pid:29032 tgid:29032 ppid:29023 task_flags:0x480140 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: b4 18 12 83 f8 07 0f 87 a2 02 00 00 89 c0 48 0f a3 05 22 be ee 0e 0f 82 74 02 00 00 8b 35 ba ee ee 0e 85 f6 0f 85 8d 00 00 00 <48> 8b 44 24 30 65 48 2b 05 39 b4 18 12 0f 85 ad 02 00 00 48 83 c4
RSP: 0018:ffffc900055bf218 EFLAGS: 00000206
RAX: 0000000000000046 RBX: ffffffff8e3c96a0 RCX: 000000002f9c2269
RDX: 0000000000000000 RSI: ffffffff8daa89dc RDI: ffffffff8bf2b400
RBP: 0000000000000002 R08: 0000000076b8c624 R09: 00000000476b8c62
R10: 0000000000000002 R11: ffff888030478b30 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
kasan_save_stack+0x33/0x60 mm/kasan/common.c:57
kasan_record_aux_stack+0xa7/0xc0 mm/kasan/generic.c:556
__call_rcu_common.constprop.0+0xa5/0xa10 kernel/rcu/tree.c:3119
security_inode_free+0xa4/0x170 security/security.c:1227
__destroy_inode+0x20a/0x740 fs/inode.c:371
destroy_inode+0x91/0x1b0 fs/inode.c:394
evict+0x599/0xad0 fs/inode.c:861
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
find_next_child+0x18f/0x280 fs/libfs.c:592
__simple_recursive_removal+0x2c4/0x610 fs/libfs.c:609
debugfs_remove+0x5d/0x80 fs/debugfs/inode.c:781
nsim_dev_debugfs_exit drivers/net/netdevsim/dev.c:371 [inline]
nsim_drv_remove+0xd2/0x1d0 drivers/net/netdevsim/dev.c:1781
device_remove+0xcb/0x170 drivers/base/dd.c:569
__device_release_driver drivers/base/dd.c:1282 [inline]
device_release_driver_internal+0x44b/0x620 drivers/base/dd.c:1305
bus_remove_device+0x22f/0x450 drivers/base/bus.c:616
device_del+0x396/0x9f0 drivers/base/core.c:3878
device_unregister+0x1d/0xe0 drivers/base/core.c:3919
nsim_bus_dev_del drivers/net/netdevsim/bus.c:491 [inline]
del_device_store+0x355/0x4a0 drivers/net/netdevsim/bus.c:244
bus_attr_store+0x74/0xb0 drivers/base/bus.c:172
sysfs_kf_write+0xf2/0x150 fs/sysfs/file.c:142
kernfs_fop_write_iter+0x3af/0x570 fs/kernfs/file.c:352
new_sync_write fs/read_write.c:593 [inline]
vfs_write+0x7d3/0x11d0 fs/read_write.c:686
ksys_write+0x12a/0x250 fs/read_write.c:738
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: 0033:0x7f3d8b98e1ff
RSP: 002b:00007ffed43b8310 EFLAGS: 00000293 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 0000000000000005 RCX: 00007f3d8b98e1ff
RDX: 0000000000000001 RSI: 00007ffed43b8360 RDI: 0000000000000005
RBP: 00007f3d8ba152cb R08: 0000000000000000 R09: 00007ffed43b8167
R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000001
R13: 00007ffed43b8360 R14: 00007f3d8c714620 R15: 0000000000000003
task:syz.0.6242 state:R running task stack:29064 pid:29168 tgid:29162 ppid:18179 task_flags:0x400040 flags:0x00080000
Call Trace:
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_lockdep_current_cpu_online+0x110/0x150 kernel/rcu/tree.c:4038
rcu_read_lock_held_common kernel/rcu/update.c:113 [inline]
rcu_read_lock_sched_held+0x29/0x70 kernel/rcu/update.c:124
task_css.constprop.0+0x66/0x130 include/linux/cgroup.h:460
mem_cgroup_from_task mm/memcontrol.c:885 [inline]
current_objcg_update+0x1cf/0x400 mm/memcontrol.c:2685
current_obj_cgroup mm/memcontrol.c:2714 [inline]
__memcg_slab_post_alloc_hook+0x652/0x880 mm/memcontrol.c:3166
memcg_slab_post_alloc_hook mm/slub.c:2338 [inline]
slab_post_alloc_hook mm/slub.c:4964 [inline]
slab_alloc_node mm/slub.c:5263 [inline]
kmem_cache_alloc_lru_noprof+0x58f/0x770 mm/slub.c:5282
sock_alloc_inode+0x25/0x1c0 net/socket.c:322
alloc_inode+0x64/0x240 fs/inode.c:346
new_inode_pseudo include/linux/fs.h:2964 [inline]
sock_alloc+0x40/0x280 net/socket.c:637
__sock_create+0xc2/0x8a0 net/socket.c:1569
sock_create net/socket.c:1663 [inline]
__sys_socket_create net/socket.c:1700 [inline]
__sys_socket+0x14d/0x260 net/socket.c:1747
__do_sys_socket net/socket.c:1761 [inline]
__se_sys_socket net/socket.c:1759 [inline]
__x64_sys_socket+0x72/0xb0 net/socket.c:1759
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: 0033:0x7f7350b8f749
RSP: 002b:00007f73519ba038 EFLAGS: 00000246 ORIG_RAX: 0000000000000029
RAX: ffffffffffffffda RBX: 00007f7350de6090 RCX: 00007f7350b8f749
RDX: 0000000000000300 RSI: 0000000000000003 RDI: 0000000000000011
RBP: 00007f7350c13f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f7350de6128 R14: 00007f7350de6090 R15: 00007ffe9f42aae8
rcu: rcu_preempt kthread starved for 10534 jiffies! g163993 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=1
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:28064 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:
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 0 Comm: swapper/1 Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
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: a6 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 19 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:ffffc90000197de8 EFLAGS: 000002c6
RAX: 0000000007c9b06f RBX: 0000000000000001 RCX: ffffffff8b7846d9
RDX: 0000000000000000 RSI: ffffffff8dacea71 RDI: ffffffff8bf2b400
RBP: ffffed1003b57498 R08: 0000000000000001 R09: ffffed10170a673d
R10: ffff8880b85339eb R11: ffff88801dabaff0 R12: 0000000000000001
R13: ffff88801daba4c0 R14: ffffffff9088b9d0 R15: 0000000000000000
FS: 0000000000000000(0000) GS:ffff8881249f5000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000200000032000 CR3: 000000000e184000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff4ff0 DR7: 0000000000000400
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
start_secondary+0x21d/0x2d0 arch/x86/kernel/smpboot.c:312
common_startup_64+0x13e/0x148