[syzbot] [nvme?] WARNING in nvmet_fc_register_targetport

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: f9a2394a2348 Merge tag 'mm-hotfixes-stable-2026-08-06-18-4..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=12e68fb9580000
kernel config: https://syzkaller.appspot.com/x/.config?x=e3f9a6906b632f9f
dashboard link: https://syzkaller.appspot.com/bug?extid=18b6b27f58e98c240814
compiler: gcc (Debian 14.2.0-19) 14.2.0, GNU ld (GNU Binutils for Debian) 2.44
userspace arch: i386

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

Downloadable assets:
disk image (non-bootable): https://storage.googleapis.com/syzbot-assets/d900f083ada3/non_bootable_disk-f9a2394a.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/969d729dd37f/vmlinux-f9a2394a.xz
kernel image: https://storage.googleapis.com/syzbot-assets/a948a2342c62/bzImage-f9a2394a.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+18b6b2...@syzkaller.appspotmail.com

R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
</TASK>
------------[ cut here ]------------
!PageLargeKmalloc(page)
WARNING: mm/slub.c:6602 at free_large_kmalloc+0xbf/0x100 mm/slub.c:6602, CPU#0: syz.2.261/6867
Modules linked in:
CPU: 0 UID: 0 PID: 6867 Comm: syz.2.261 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014
RIP: 0010:free_large_kmalloc+0xbf/0x100 mm/slub.c:6602
Code: 28 90 0f 0b 90 80 3d e8 ab 9c 0e 00 0f 84 c7 6e b7 fe 48 8b 74 24 28 48 89 ef e8 7c 3a 0c 00 b8 00 f0 ff ff 45 31 ed eb 9d 90 <0f> 0b 90 48 83 c4 08 48 89 df 48 c7 c6 24 df 18 8e 5b 5d 41 5c 41
RSP: 0018:ffffc9000735fa10 EFLAGS: 00010202
RAX: 00000000000000ff RBX: ffffea00017e83c0 RCX: 000000000000002e
RDX: 0000000000000000 RSI: ffff88805fa0ff20 RDI: ffffea00017e83c0
RBP: ffff88805fa0ff20 R08: ffff888023ddfc00 R09: 00000000ffffffff
R10: ffffffffffffffff R11: 0000000000000000 R12: 00000000ffffffff
R13: 1ffff92000e6bf5b R14: dead000000000122 R15: ffff888023ddfc90
FS: 0000000000000000(0000) GS:ffff888096bf4000(0063) knlGS:00000000f5456b40
CS: 0010 DS: 002b ES: 002b CR0: 0000000080050033
CR2: 0000000000000000 CR3: 0000000025d36000 CR4: 0000000000352ef0
Call Trace:
<TASK>
nvmet_fc_alloc_ls_iodlist drivers/nvme/target/fc.c:569 [inline]
nvmet_fc_register_targetport+0x114c/0x1c30 drivers/nvme/target/fc.c:1411
fcloop_create_target_port+0x156/0x5a0 drivers/nvme/target/fcloop.c:1558
dev_attr_store+0x58/0x80 drivers/base/core.c:2505
sysfs_kf_write+0xf2/0x150 fs/sysfs/file.c:145
kernfs_fop_write_iter+0x3e0/0x5f0 fs/kernfs/file.c:345
new_sync_write fs/read_write.c:595 [inline]
vfs_write+0x6ac/0x1050 fs/read_write.c:687
ksys_write+0x12a/0x250 fs/read_write.c:739
do_syscall_32_irqs_on arch/x86/entry/syscall_32.c:83 [inline]
__do_fast_syscall_32+0xe7/0x970 arch/x86/entry/syscall_32.c:307
do_fast_syscall_32+0x32/0x70 arch/x86/entry/syscall_32.c:332
entry_SYSENTER_compat_after_hwframe+0x84/0x8e
RIP: 0023:0xf7f96fec
Code: Unable to access opcode bytes at 0xf7f96fc2.
RSP: 002b:00000000f545650c EFLAGS: 00000292 ORIG_RAX: 0000000000000004
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000080000200
RDX: 000000000000002f RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
</TASK>


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