R13: 00007f08b02e1fac R14: 00007f08b02e1fa0 R15: 00007f08b02e1fa0
 </TASK>
kobject_add_internal failed for md0 with -EEXIST, don't try to register things with the same name in the same directory.
------------[ cut here ]------------
WARNING: CPU: 1 PID: 4751 at block/genhd.c:547 device_add_disk+0x731/0xd00 block/genhd.c:545
Modules linked in:
CPU: 1 PID: 4751 Comm: syz.4.285 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
RIP: 0010:device_add_disk+0x731/0xd00 block/genhd.c:547
Code: b9 00 00 00 00 00 fc ff df 0f b6 04 08 84 c0 0f 85 a9 04 00 00 8b 33 48 c7 c7 c0 f2 90 8c e8 86 3e 37 00 eb 05 e8 cf 8f a6 fd <0f> 0b 41 bd 01 00 00 00 44 89 e8 48 83 c4 50 5b 41 5c 41 5d 41 5e
RSP: 0018:ffffc9000580fa00 EFLAGS: 00010293
RAX: ffffffff83d27fd1 RBX: ffff88805d584400 RCX: ffff888027f81dc0
RDX: 0000000000000000 RSI: 0000000000000009 RDI: 0000000000000103
RBP: 0000000000000009 R08: ffff88805b710c3b R09: 1ffff1100b6e2187
R10: dffffc0000000000 R11: ffffed100b6e2188 R12: ffff88805b710bc0
R13: 1ffff1100bab0894 R14: 1ffff1100bab0880 R15: ffff88805b710c00
FS:  0000555572c59500(0000) GS:ffff8880b9100000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b31563fff CR3: 0000000059803000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 add_disk include/linux/genhd.h:200 [inline]
 md_alloc+0x80e/0xc10 drivers/md/md.c:5782
 add_named_array+0x1bd/0x290 drivers/md/md.c:-1
 param_attr_store+0x20a/0x300 kernel/params.c:585
 module_attr_store+0x5b/0x80 kernel/params.c:905
 kernfs_fop_write_iter+0x3a8/0x500 fs/kernfs/file.c:296
 call_write_iter include/linux/fs.h:2179 [inline]
 new_sync_write fs/read_write.c:507 [inline]
 vfs_write+0x748/0xd70 fs/read_write.c:594
 ksys_write+0x153/0x260 fs/read_write.c:647
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f08b005a159
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:00007ffc1a4f5408 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007f08b02e1fa0 RCX: 00007f08b005a159
RDX: 0000000000000003 RSI: 0000200000000200 RDI: 0000000000000003
RBP: 00007f08b00f1024 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f08b02e1fac R14: 00007f08b02e1fa0 R15: 00007f08b02e1fa0
 </TASK>