------------[ cut here ]------------
kmem_cache of name '9p-fcall-cache' already exists
WARNING: CPU: 0 PID: 5111 at mm/slab_common.c:108 kmem_cache_sanity_check mm/slab_common.c:107 [inline]
WARNING: CPU: 0 PID: 5111 at mm/slab_common.c:108 __kmem_cache_create_args+0xa7/0x350 mm/slab_common.c:294
Modules linked in:
CPU: 0 UID: 0 PID: 5111 Comm: syz-executor265 Not tainted 6.11.0-syzkaller-08068-g1ec6d097897a #0
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
RIP: 0010:kmem_cache_sanity_check mm/slab_common.c:107 [inline]
RIP: 0010:__kmem_cache_create_args+0xa7/0x350 mm/slab_common.c:294
Code: 8e 48 8b 1b 48 39 eb 74 25 48 8b 7b f8 4c 89 fe e8 2e d5 dd 09 85 c0 75 e8 90 48 c7 c7 7e 8b 0a 8e 4c 89 fe e8 ca 75 79 ff 90 <0f> 0b 90 90 4c 89 ff be 20 00 00 00 e8 88 d6 dd 09 48 85 c0 0f 85
RSP: 0018:ffffc90002e3f788 EFLAGS: 00010246
RAX: 33540304de2d8800 RBX: ffff88803e2091a8 RCX: ffff88800016a440
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffffff8ea1f420 R08: ffffffff8155a922 R09: 1ffff11003f8519a
R10: dffffc0000000000 R11: ffffed1003f8519b R12: 0000000000020018
R13: 0000000000000000 R14: ffffc90002e3f860 R15: ffffffff8d2d7900
FS:  000055556978a380(0000) GS:ffff88801fc00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055d25b572688 CR3: 000000003f530000 CR4: 0000000000350ef0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 kmem_cache_create_usercopy include/linux/slab.h:361 [inline]
 p9_client_create+0xba5/0x1110 net/9p/client.c:1042
 v9fs_session_init+0x1e4/0x1b80 fs/9p/v9fs.c:410
 v9fs_mount+0xcf/0xaa0 fs/9p/vfs_super.c:122
 legacy_get_tree+0xee/0x190 fs/fs_context.c:662
 vfs_get_tree+0x90/0x2b0 fs/super.c:1800
 do_new_mount+0x2be/0xb40 fs/namespace.c:3507
 do_mount fs/namespace.c:3847 [inline]
 __do_sys_mount fs/namespace.c:4055 [inline]
 __se_sys_mount+0x2d6/0x3c0 fs/namespace.c:4032
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f3c2fe9fe69
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 c1 17 00 00 90 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 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffe2bc6e798 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007f3c2fee904e RCX: 00007f3c2fe9fe69
RDX: 0000000020000040 RSI: 0000000020000000 RDI: 0000000000000000
RBP: 00000000000f4240 R08: 0000000020000280 R09: 00000000000000a0
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001
R13: 00007ffe2bc6e9b8 R14: 00007ffe2bc6e7c0 R15: 00007ffe2bc6e7b0
 </TASK>