[v6.1] INFO: rcu detected stall in dev_ioctl

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 1989cd3d56e2 Linux 6.1.167
git tree: linux-6.1.y
console output: https://syzkaller.appspot.com/x/log.txt?x=14634e06580000
kernel config: https://syzkaller.appspot.com/x/.config?x=f0605c5af04d7603
dashboard link: https://syzkaller.appspot.com/bug?extid=f01cb5bfb3ee48171ef1
compiler: Debian clang version 21.1.8 (++20251221033036+2078da43e25a-1~exp1~20251221153213.50), Debian LLD 21.1.8

Unfortunately, I don't have any reproducer for this issue yet.

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/3e0cf5574b81/disk-1989cd3d.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/0c1152de55b1/vmlinux-1989cd3d.xz
kernel image: https://storage.googleapis.com/syzbot-assets/3fe87e3166b1/bzImage-1989cd3d.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+f01cb5...@syzkaller.appspotmail.com

rcu: INFO: rcu_preempt detected expedited stalls on CPUs/tasks: { 0-.... } 2635 jiffies s: 208701 root: 0x1/.
rcu: blocking rcu_node structures (internal RCU debug):
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 23575 Comm: syz.6.4661 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026
RIP: 0010:perf_trace_run_bpf_submit+0x7/0x1c0 kernel/events/core.c:10024
Code: 02 e9 15 ff ff ff 89 d9 80 e1 07 80 c1 03 38 c1 0f 8c 42 ff ff ff 48 89 df e8 45 e0 2d 00 e9 35 ff ff ff 55 41 57 41 56 41 55 <41> 54 53 48 83 ec 10 4d 89 ce 4c 89 44 24 08 49 89 cd 48 89 14 24
RSP: 0018:ffffc900000078a8 EFLAGS: 00000046
RAX: 0000000000000000 RBX: dffffc0000000000 RCX: ffffffff8cb7fae0
RDX: 0000000000000001 RSI: 0000000000000014 RDI: ffffe8ffffce7000
RBP: ffffc900000079b8 R08: 0000000000000001 R09: ffff8880b8e35558
R10: dffffc0000000000 R11: fffffbfff1c3fbde R12: 00000000092dcd73
R13: ffffe8ffffce700c R14: ffffe8ffffce7000 R15: 1ffff92000000f20
FS: 00007f27a31af6c0(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f32bf217dac CR3: 0000000063cad000 CR4: 00000000003506f0
DR0: 0000200000000300 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
<IRQ>
perf_trace_preemptirq_template+0x268/0x320 include/trace/events/preemptirq.h:14
trace_irq_disable include/trace/events/preemptirq.h:36 [inline]
trace_hardirqs_off_finish+0x13f/0x180 kernel/trace/trace_preemptirq.c:67
irqentry_enter+0x33/0x50 kernel/entry/common.c:382
sysvec_irq_work+0xa/0xc0 arch/x86/kernel/irq_work.c:17
asm_sysvec_irq_work+0x16/0x20 arch/x86/include/asm/idtentry.h:728
RIP: 0010:rcu_read_unlock_special+0x7f/0x510 kernel/rcu/tree_plugin.h:685
Code: eb 03 48 b8 f1 f1 f1 f1 f8 f2 f2 f2 4a 89 04 2b 42 c7 44 2b 08 f8 f3 f3 f3 65 44 8b 35 d2 33 95 7e 41 f7 c6 00 00 f0 00 74 40 <48> c7 44 24 40 0e 36 e0 45 4a c7 04 2b 00 00 00 00 42 c7 44 2b 08
RSP: 0018:ffffc90000007ac0 EFLAGS: 00000206
RAX: 27f9ce3c36d7e200 RBX: 1ffff92000000f60 RCX: 27f9ce3c36d7e200
RDX: dffffc0000000000 RSI: ffffffff8a8c10a0 RDI: ffffffff8adf0d20
RBP: ffffc90000007bb0 R08: ffffffff90af724f R09: 1ffffffff215ee49
R10: dffffc0000000000 R11: fffffbfff215ee4a R12: 0000000000000246
R13: dffffc0000000000 R14: ffff8880b8e3b900 R15: 0000000000000001
__rcu_read_unlock+0x78/0xd0 kernel/rcu/tree_plugin.h:426
rcu_read_unlock include/linux/rcupdate.h:823 [inline]
ieee80211_iterate_active_interfaces_atomic+0x156/0x170 net/mac80211/util.c:826
mac80211_hwsim_beacon+0xb7/0x1b0 drivers/net/wireless/mac80211_hwsim.c:2147
__run_hrtimer kernel/time/hrtimer.c:1747 [inline]
__hrtimer_run_queues+0x54a/0xd50 kernel/time/hrtimer.c:1811
hrtimer_run_softirq+0x183/0x2a0 kernel/time/hrtimer.c:1828
handle_softirqs+0x2a1/0x930 kernel/softirq.c:596
__do_softirq kernel/softirq.c:630 [inline]
invoke_softirq kernel/softirq.c:470 [inline]
__irq_exit_rcu+0x13b/0x230 kernel/softirq.c:679
irq_exit_rcu+0x5/0x20 kernel/softirq.c:691
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1118 [inline]
sysvec_apic_timer_interrupt+0xa0/0xc0 arch/x86/kernel/apic/apic.c:1118
</IRQ>
<TASK>
asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:691
RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline]
RIP: 0010:_raw_spin_unlock_irqrestore+0xbc/0x120 kernel/locking/spinlock.c:194
Code: c7 44 24 20 00 00 00 00 9c 8f 44 24 20 f7 44 24 20 00 02 00 00 41 c6 04 07 f8 75 4b f7 c3 00 02 00 00 74 01 fb bf 01 00 00 00 <e8> df 0d 21 f7 65 8b 05 30 91 ca 75 85 c0 74 3c 48 c7 04 24 0e 36
RSP: 0018:ffffc90005257120 EFLAGS: 00000206
RAX: dffffc0000000004 RBX: 0000000000000a06 RCX: 27f9ce3c36d7e200
RDX: dffffc0000000000 RSI: ffffffff8a8c10a0 RDI: 0000000000000001
RBP: ffffc900052571a8 R08: ffffffff90af724f R09: 1ffffffff215ee49
R10: dffffc0000000000 R11: fffffbfff215ee4a R12: dffffc0000000000
R13: ffff888038170000 R14: ffffffff96e725c0 R15: 1ffff92000a4ae24
__debug_check_no_obj_freed lib/debugobjects.c:988 [inline]
debug_check_no_obj_freed+0x515/0x530 lib/debugobjects.c:1009
free_pages_prepare mm/page_alloc.c:1492 [inline]
free_pcp_prepare mm/page_alloc.c:1536 [inline]
free_unref_page_prepare+0x2a6/0x9a0 mm/page_alloc.c:3413
free_unref_page+0x2e/0x3f0 mm/page_alloc.c:3508
qlink_free mm/kasan/quarantine.c:168 [inline]
qlist_free_all+0x76/0xe0 mm/kasan/quarantine.c:187
kasan_quarantine_reduce+0x144/0x160 mm/kasan/quarantine.c:294
__kasan_slab_alloc+0x1e/0x80 mm/kasan/common.c:306
kasan_slab_alloc include/linux/kasan.h:201 [inline]
slab_post_alloc_hook+0x4b/0x480 mm/slab.h:737
slab_alloc_node mm/slub.c:3359 [inline]
slab_alloc mm/slub.c:3367 [inline]
__kmem_cache_alloc_lru mm/slub.c:3374 [inline]
kmem_cache_alloc+0x123/0x2f0 mm/slub.c:3383
kmem_cache_zalloc include/linux/slab.h:689 [inline]
__kernfs_new_node+0xe1/0x810 fs/kernfs/dir.c:614
kernfs_new_node+0x148/0x250 fs/kernfs/dir.c:690
__kernfs_create_file+0x47/0x2e0 fs/kernfs/file.c:1068
sysfs_add_file_mode_ns+0x234/0x2f0 fs/sysfs/file.c:294
sysfs_create_file_ns+0x128/0x1b0 fs/sysfs/file.c:355
sysfs_create_file include/linux/sysfs.h:623 [inline]
device_create_file drivers/base/core.c:3055 [inline]
device_add+0x54f/0xfb0 drivers/base/core.c:3641
netdev_register_kobject+0x184/0x320 net/core/net-sysfs.c:2013
register_netdevice+0x12dc/0x1b00 net/core/dev.c:10230
ip6_tnl_create2+0x80/0x140 net/ipv6/ip6_tunnel.c:261
ip6_tnl_create net/ipv6/ip6_tunnel.c:311 [inline]
ip6_tnl_locate+0x731/0x830 net/ipv6/ip6_tunnel.c:361
ip6_tnl_siocdevprivate+0x5ef/0xaf0 net/ipv6/ip6_tunnel.c:1672
dev_siocdevprivate net/core/dev_ioctl.c:287 [inline]
dev_ifsioc+0xa4a/0xd40 net/core/dev_ioctl.c:392
dev_ioctl+0x5f8/0xe80 net/core/dev_ioctl.c:597
sock_ioctl+0x691/0x710 net/socket.c:1245
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:870 [inline]
__se_sys_ioctl+0xfa/0x170 fs/ioctl.c:856
do_syscall_x64 arch/x86/entry/common.c:46 [inline]
do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f27a239c819
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f27a31af028 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f27a2615fa0 RCX: 00007f27a239c819
RDX: 0000200000000080 RSI: 00000000000089f1 RDI: 000000000000000c
RBP: 00007f27a2432c91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f27a2616038 R14: 00007f27a2615fa0 R15: 00007ffcbbfb0e08
</TASK>


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