[syzbot] [kernel?] WARNING in __dynamic_dev_dbg

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 21d6ac051080 Merge branch 'for-next/core' into for-kernelci
git tree: git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci
console output: https://syzkaller.appspot.com/x/log.txt?x=1022e279580000
kernel config: https://syzkaller.appspot.com/x/.config?x=d1128bc53f2ef7f3
dashboard link: https://syzkaller.appspot.com/bug?extid=6102f1c3a0ea8073fd64
compiler: Debian clang version 22.1.8 (++20260613092233+e80beda6e255-1~exp1~20260613092250.77), Debian LLD 22.1.8
userspace arch: arm64

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

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/88380e2ddcb9/disk-21d6ac05.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/5dba5c2896b7/vmlinux-21d6ac05.xz
kernel image: https://storage.googleapis.com/syzbot-assets/52ac739e37e0/Image-21d6ac05.gz.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+6102f1...@syzkaller.appspotmail.com

------------[ cut here ]------------
field width 67108864 out of range
WARNING: lib/vsprintf.c:2650 at set_field_width lib/vsprintf.c:2650 [inline], CPU#0: syz.6.1148/9267
WARNING: lib/vsprintf.c:2650 at vsnprintf+0xb9c/0xd10 lib/vsprintf.c:2914, CPU#0: syz.6.1148/9267
Modules linked in:
CPU: 0 UID: 0 PID: 9267 Comm: syz.6.1148 Tainted: G L syzkaller #0 PREEMPT
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/07/2026
pstate: 634000c5 (nZCv daIF +PAN -UAO +TCO +DIT -SSBS BTYPE=--)
pc : set_field_width lib/vsprintf.c:2650 [inline]
pc : vsnprintf+0xb9c/0xd10 lib/vsprintf.c:2914
lr : set_field_width lib/vsprintf.c:2650 [inline]
lr : vsnprintf+0xb9c/0xd10 lib/vsprintf.c:2914
sp : ffff8000946e6b10
x29: ffff8000946e6b60 x28: 00000000007fffff x27: ffff800087471e82
x26: 0000000004000000 x25: ffff8000946e6bd8 x24: 0000000000000402
x23: ffff8000946e6f18 x22: ffff800087b3ed00 x21: ffff8000946e6bf0
x20: ffff8000946e6ecb x19: dfff800000000000 x18: 0000000000000000
x17: 0000000000000000 x16: 0000000000000000 x15: 0000000020000040
x14: 0000000000000000 x13: 0000000000000001 x12: 0000000000000000
x11: 0000000000000000 x10: 0000000000080000 x9 : d2e0bfbdf6510800
x8 : d2e0bfbdf6510800 x7 : ffff80008048c5b8 x6 : 0000000000000000
x5 : 0000000000000001 x4 : 0000000000000000 x3 : ffff8000802f6830
x2 : 0000000100000000 x1 : ffff0000f664d7c0 x0 : 0000000000000001
Call trace:
set_field_width lib/vsprintf.c:2650 [inline] (P)
vsnprintf+0xb9c/0xd10 lib/vsprintf.c:2914 (P)
va_format lib/vsprintf.c:1725 [inline]
pointer+0x5e8/0x6b4 lib/vsprintf.c:2573
vsnprintf+0x618/0xd10 lib/vsprintf.c:2949
vprintk_store+0x344/0xb94 kernel/printk/printk.c:2307
vprintk_emit+0x1bc/0x514 kernel/printk/printk.c:2455
dev_vprintk_emit+0x2ec/0x3b4 drivers/base/core.c:4996
dev_printk_emit+0xe0/0x130 drivers/base/core.c:5007
__dynamic_dev_dbg+0x1b4/0x254 lib/dynamic_debug.c:904
dtv_property_process_get+0x26bc/0x2838 drivers/media/dvb-core/dvb_frontend.c:1594
dvb_get_property drivers/media/dvb-core/dvb_frontend.c:2396 [inline]
dvb_frontend_handle_ioctl+0x1644/0x2424 drivers/media/dvb-core/dvb_frontend.c:2477
dvb_frontend_do_ioctl+0x124/0x278 drivers/media/dvb-core/dvb_frontend.c:2100
dvb_usercopy+0x2a4/0x4d4 drivers/media/dvb-core/dvbdev.c:996
dvb_frontend_ioctl+0x68/0x8c drivers/media/dvb-core/dvb_frontend.c:2114
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:597 [inline]
__se_sys_ioctl fs/ioctl.c:583 [inline]
__arm64_sys_ioctl+0x154/0x1cc fs/ioctl.c:583
__invoke_syscall arch/arm64/kernel/syscall.c:35 [inline]
invoke_syscall+0x98/0x244 arch/arm64/kernel/syscall.c:49
el0_svc_common+0xec/0x23c arch/arm64/kernel/syscall.c:121
do_el0_svc+0x4c/0x5c arch/arm64/kernel/syscall.c:140
el0_svc+0x64/0x260 arch/arm64/kernel/entry-common.c:758
el0t_64_sync_handler+0x44/0x104 arch/arm64/kernel/entry-common.c:777
el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:590
irq event stamp: 150
hardirqs last enabled at (149): [<ffff80008690f4e0>] irqentry_exit_to_kernel_mode_after_preempt include/linux/irq-entry-common.h:507 [inline]
hardirqs last enabled at (149): [<ffff80008690f4e0>] __arm64_exit_to_kernel_mode+0x64/0x78 arch/arm64/kernel/entry-common.c:60
hardirqs last disabled at (150): [<ffff80008048f368>] vprintk_store+0x13c/0xb94 kernel/printk/printk.c:2287
softirqs last enabled at (114): [<ffff80008013b050>] local_bh_enable include/linux/bottom_half.h:33 [inline]
softirqs last enabled at (114): [<ffff80008013b050>] put_cpu_fpsimd_context arch/arm64/kernel/fpsimd.c:251 [inline]
softirqs last enabled at (114): [<ffff80008013b050>] fpsimd_restore_current_state+0x39c/0x9c8 arch/arm64/kernel/fpsimd.c:1797
softirqs last disabled at (112): [<ffff80008013acf8>] local_bh_disable include/linux/bottom_half.h:20 [inline]
softirqs last disabled at (112): [<ffff80008013acf8>] get_cpu_fpsimd_context arch/arm64/kernel/fpsimd.c:234 [inline]
softirqs last disabled at (112): [<ffff80008013acf8>] fpsimd_restore_current_state+0x44/0x9c8 arch/arm64/kernel/fpsimd.c:1790
---[ end trace 0000000000000000 ]---


---
This report is generated by a bot. It may contain errors.
See https://goo.gl/tpsmEJ for more information about syzbot.
syzbot engineers can be reached at syzk...@googlegroups.com.

syzbot will keep track of this issue. See:
https://goo.gl/tpsmEJ#status for how to communicate with syzbot.

If the report is already addressed, let syzbot know by replying with:
#syz fix: exact-commit-title

If you want to overwrite report's subsystems, reply with:
#syz set subsystems: new-subsystem
(See the list of subsystem names on the web dashboard)

If the report is a duplicate of another one, reply with:
#syz dup: exact-subject-of-another-report

If you want to undo deduplication, reply with:
#syz undup