[syzbot] [net?] WARNING in add_timer

[syzbot <syzbot+07b635b9c111c566af8b@syzkaller.appspotmail.com>]

Hello,

syzbot found the following issue on:

HEAD commit:    63a796558bc2 Revert "net: usb: asix: ax88772: drop phylink..
git tree:       net
console output: https://syzkaller.appspot.com/x/log.txt?x=11906b12580000
kernel config:  https://syzkaller.appspot.com/x/.config?x=9c302bcfb26a48af
dashboard link: https://syzkaller.appspot.com/bug?extid=07b635b9c111c566af8b
compiler:       Debian clang version 20.1.8 (++20250708063551+0c9f909b7976-1~exp1~20250708183702.136), Debian LLD 20.1.8

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

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/2ee11780421b/disk-63a79655.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/ea93cc1dbd6d/vmlinux-63a79655.xz
kernel image: https://storage.googleapis.com/syzbot-assets/1ca443049a6a/bzImage-63a79655.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+07b635b9c111c566af8b@syzkaller.appspotmail.com

------------[ cut here ]------------
WARNING: CPU: 1 PID: 6273 at kernel/time/timer.c:1247 add_timer+0x73/0x90 kernel/time/timer.c:1247
Modules linked in:
CPU: 1 UID: 0 PID: 6273 Comm: syz.4.86 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
RIP: 0010:add_timer+0x73/0x90 kernel/time/timer.c:1247
Code: e8 03 42 80 3c 38 00 74 05 e8 69 1d 76 00 48 8b 73 10 48 89 df ba 04 00 00 00 5b 41 5e 41 5f e9 d3 ef ff ff e8 ee ab 12 00 90 <0f> 0b 90 5b 41 5e 41 5f c3 cc cc cc cc cc 66 66 66 66 66 66 2e 0f
RSP: 0018:ffffc9000b847980 EFLAGS: 00010293
RAX: ffffffff81ad0262 RBX: ffffffff8f742880 RCX: ffff88802e6e9e00
RDX: 0000000000000000 RSI: 00000000000061d8 RDI: ffffffff8f742880
RBP: ffffc9000b847ac8 R08: ffff88801b68f8fb R09: 1ffff110036d1f1f
R10: dffffc0000000000 R11: ffffed10036d1f20 R12: 00000000000061d8
R13: ffff88807e627000 R14: ffffffff8f742888 R15: dffffc0000000000
FS:  00007fdd1c7e46c0(0000) GS:ffff888125d18000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000056332c8bc2b8 CR3: 0000000028848000 CR4: 00000000003526f0
Call Trace:
 <TASK>
 mpc_timer_refresh net/atm/mpc.c:1419 [inline]
 atm_mpoa_mpoad_attach net/atm/mpc.c:802 [inline]
 atm_mpoa_ioctl+0x2c3/0xca0 net/atm/mpc.c:1460
 do_vcc_ioctl+0x36d/0x9e0 net/atm/ioctl.c:159
 svc_ioctl+0x1ee/0x770 net/atm/svc.c:611
 sock_do_ioctl+0xdc/0x300 net/socket.c:1238
 sock_ioctl+0x576/0x790 net/socket.c:1359
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:598 [inline]
 __se_sys_ioctl+0xfc/0x170 fs/ioctl.c:584
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fdd1b98eba9
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fdd1c7e4038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007fdd1bbd5fa0 RCX: 00007fdd1b98eba9
RDX: 0000000000000000 RSI: 00000000000061d8 RDI: 0000000000000004
RBP: 00007fdd1c7e4090 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001
R13: 00007fdd1bbd6038 R14: 00007fdd1bbd5fa0 R15: 00007fffd3ee7758
 </TASK>


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