[BUG] WARNING: kobject bug in vdpasim_blk_dev_add
From: Farhad Alemi
Date: Fri Sep 11 2026 - 11:34:04 EST
Hello,
Reporting the following crash:
Linux version 7.3.0-rc2 50d05c7c76c96b90462f24debacca971d2e86713
Build Config: UpstreamAppArmorKASAN (KASAN + UBSAN, panic_on_warn=1)
[ 43.937539][ T9492] kobject: (ffff888107e94000): attempted to be
registered with empty name!
[ 43.937548][ T9492] WARNING: lib/kobject.c:221 at
kobject_add_internal+0x13e/0xd00, CPU#1: repro/9492
[ 43.939713][ T9492] Modules linked in:
[ 43.940114][ T9492] CPU: 1 UID: 0 PID: 9492 Comm: repro Not tainted
7.3.0-rc2-00099-g50d05c7c76c9 #1 PREEMPT(full)
[ 43.941058][ T9492] Hardware name: QEMU Standard PC (Q35 + ICH9,
2009), BIOS 1.17.0-debian-1.17.0-1ubuntu1 04/01/2014
[ 43.942114][ T9492] RIP: 0010:kobject_add_internal+0x141/0xd00
[ 43.942670][ T9492] Code: e9 da 00 00 00 e8 ff 0f 03 f6 b8 fe ff ff
ff e9 0a 07 00 00 e8 f0 0f 03 f6 eb 05 e8 e9 0f 03 f6 48 8d 3d 72 80
a4 04 48 89 de <67> 48 0f b9 3a b8 ea ff ff ff e9 e5 06 00 00 4c 8d 73
20 4d 89 f5
[ 43.945337][ T9492] RSP: 0018:ffffc90007b5f2d8 EFLAGS: 00010293
[ 43.945976][ T9492] RAX: ffffffff8bc48c97 RBX: ffff888107e94000
RCX: ffff88802e21a640
[ 43.946731][ T9492] RDX: 0000000000000000 RSI: ffff888107e94000
RDI: ffffffff90690d10
[ 43.947516][ T9492] RBP: 0000000000000000 R08: ffffc90007b5f3b7
R09: 0000000000000000
[ 43.948287][ T9492] R10: ffffc90007b5f3a0 R11: fffff52000f6be77
R12: 1ffff11020fd2800
[ 43.949058][ T9492] R13: dffffc0000000000 R14: ffff8881054a19e0
R15: dffffc0000000000
[ 43.949825][ T9492] FS: 000000002a38d400(0000)
GS:ffff8881da588000(0000) knlGS:0000000000000000
[ 43.950684][ T9492] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 43.951309][ T9492] CR2: 00000000004b9200 CR3: 000000010a760000
CR4: 0000000000752ef0
[ 43.952087][ T9492] PKRU: 55555554
[ 43.952441][ T9492] Call Trace:
[ 43.952753][ T9492] <TASK>
[ 43.953035][ T9492] kobject_add+0x163/0x240
[ 43.953453][ T9492] ? __pfx_kobject_add+0x10/0x10
[ 43.953907][ T9492] ? bus_get_dev_root+0x127/0x160
[ 43.954415][ T9492] ? get_device_parent+0x38c/0x3a0
[ 43.954916][ T9492] ? __pfx_klist_children_get+0x10/0x10
[ 43.955491][ T9492] device_add+0x408/0xb90
[ 43.955890][ T9492] vdpasim_blk_dev_add+0x1e2/0x2a0
[ 43.956363][ T9492] ? __pfx_vdpasim_blk_dev_add+0x10/0x10
[ 43.956874][ T9492] ? __pfx_vdpasim_blk_work+0x10/0x10
[ 43.957364][ T9492] ? __pfx_vdpasim_blk_get_config+0x10/0x10
[ 43.957899][ T9492] ? __pfx_vdpasim_blk_free+0x10/0x10
[ 43.958391][ T9492] ? vdpa_mgmtdev_get_from_attr+0x2bb/0x2d0
[ 43.958928][ T9492] vdpa_nl_cmd_dev_add_set_doit+0xa75/0xbc0
[ 43.959469][ T9492] ? __pfx_vdpa_nl_cmd_dev_add_set_doit+0x10/0x10
[ 43.960049][ T9492] ? __nla_parse+0x40/0x60
[ 43.960461][ T9492] ? genl_family_rcv_msg_attrs_parse+0x20b/0x2f0
[ 43.961047][ T9492] ? genl_family_rcv_msg_attrs_parse+0x265/0x2f0
[ 43.961643][ T9492] genl_family_rcv_msg_doit+0x22a/0x330
[ 43.962175][ T9492] ? __asan_memcpy+0x40/0x70
[ 43.962625][ T9492] ? __pfx_genl_family_rcv_msg_doit+0x10/0x10
[ 43.963212][ T9492] ? bpf_lsm_capable+0x9/0x20
[ 43.963664][ T9492] ? security_capable+0x7e/0x2c0
[ 43.964157][ T9492] genl_rcv_msg+0x61c/0x7a0
[ 43.964598][ T9492] ? __pfx_genl_rcv_msg+0x10/0x10
[ 43.965086][ T9492] ? __pfx_vdpa_nl_cmd_dev_add_set_doit+0x10/0x10
[ 43.966175][ T9492] netlink_rcv_skb+0x232/0x4b0
[ 43.966616][ T9492] ? __pfx_genl_rcv_msg+0x10/0x10
[ 43.967080][ T9492] ? __pfx_netlink_rcv_skb+0x10/0x10
[ 43.967568][ T9492] ? down_read+0x2be/0x330
[ 43.967979][ T9492] genl_rcv+0x28/0x40
[ 43.968351][ T9492] netlink_unicast+0x75e/0x8e0
[ 43.968797][ T9492] netlink_sendmsg+0x813/0xb40
[ 43.969239][ T9492] ? __pfx_netlink_sendmsg+0x10/0x10
[ 43.969721][ T9492] ? apparmor_socket_sendmsg+0x95/0x390
[ 43.970229][ T9492] ? __pfx_netlink_sendmsg+0x10/0x10
[ 43.970710][ T9492] sock_sendmsg_nosec+0x13a/0x180
[ 43.971174][ T9492] __sys_sendto+0x408/0x5a0
[ 43.971622][ T9492] ? __pfx___sys_sendto+0x10/0x10
[ 43.972114][ T9492] ? fd_install+0x94/0x3d0
[ 43.972543][ T9492] ? fd_install+0x309/0x3d0
[ 43.972982][ T9492] __x64_sys_sendto+0xde/0x100
[ 43.973455][ T9492] do_syscall_64+0x155/0x510
[ 43.973925][ T9492] ? trace_irq_disable+0x3b/0x140
[ 43.974437][ T9492] ? entry_SYSCALL_64_after_hwframe+0x77/0x7f
[ 43.975034][ T9492] ? clear_bhb_loop+0x30/0x80
[ 43.975572][ T9492] entry_SYSCALL_64_after_hwframe+0x77/0x7f
[ 43.976138][ T9492] RIP: 0033:0x42ce46
[ 43.976516][ T9492] Code: 47 ba 04 00 00 00 48 c7 c0 f0 ff ff ff 64
89 10 48 c7 c2 ff ff ff ff c9 48 89 d0 c3 0f 1f 84 00 00 00 00 00 48
8b 45 10 0f 05 <48> 89 c2 48 3d 00 f0 ff ff 77 0f c9 48 89 d0 c3 66 2e
0f 1f 84 00
[ 43.978228][ T9492] RSP: 002b:00007ffc31f8bd20 EFLAGS: 00000202
ORIG_RAX: 000000000000002c
[ 43.978979][ T9492] RAX: ffffffffffffffda RBX: 0000000000000001
RCX: 000000000042ce46
[ 43.979689][ T9492] RDX: 000000000000002c RSI: 00007ffc31f8bda0
RDI: 0000000000000003
[ 43.980398][ T9492] RBP: 00007ffc31f8bd30 R08: 00007ffc31f8bd94
R09: 000000000000000c
[ 43.981108][ T9492] R10: 0000000000000000 R11: 0000000000000202
R12: 00007ffc31f8c208
[ 43.981845][ T9492] R13: 00007ffc31f8c218 R14: 0000000000000002
R15: 00000000004ad140
[ 43.982610][ T9492] </TASK>
[ 43.982915][ T9492] Kernel panic - not syncing: kernel: panic_on_warn set ...
[ 43.983606][ T9492] CPU: 1 UID: 0 PID: 9492 Comm: repro Not tainted
7.3.0-rc2-00099-g50d05c7c76c9 #1 PREEMPT(full)
[ 43.984545][ T9492] Hardware name: QEMU Standard PC (Q35 + ICH9,
2009), BIOS 1.17.0-debian-1.17.0-1ubuntu1 04/01/2014
[ 43.985557][ T9492] Call Trace:
[ 43.985863][ T9492] <TASK>
[ 43.986163][ T9492] vpanic+0x56d/0xa60
[ 43.986557][ T9492] ? __pfx__printk+0x10/0x10
[ 43.987007][ T9492] ? __pfx_vpanic+0x10/0x10
[ 43.987444][ T9492] ? is_bpf_text_address+0x292/0x2b0
[ 43.987947][ T9492] ? is_bpf_text_address+0x26/0x2b0
[ 43.988428][ T9492] panic+0xc5/0xd0
[ 43.988774][ T9492] ? __pfx_panic+0x10/0x10
[ 43.989189][ T9492] __warn+0x315/0x4c0
[ 43.989557][ T9492] ? kobject_add_internal+0x13e/0xd00
[ 43.990048][ T9492] ? kobject_add_internal+0x13e/0xd00
[ 43.990534][ T9492] __report_bug+0x273/0x580
[ 43.990955][ T9492] ? kobject_add_internal+0x13e/0xd00
[ 43.991446][ T9492] ? __pfx___report_bug+0x10/0x10
[ 43.991908][ T9492] ? kasan_save_track+0x4f/0x80
[ 43.992360][ T9492] ? __kasan_kmalloc+0x93/0xb0
[ 43.992834][ T9492] ? __kmalloc_cache_noprof+0x325/0x610
[ 43.993388][ T9492] ? device_add+0xbe/0xb90
[ 43.993817][ T9492] report_bug_entry+0x19b/0x290
[ 43.994293][ T9492] ? kobject_add_internal+0x141/0xd00
[ 43.994778][ T9492] ? kobject_add_internal+0x146/0xd00
[ 43.995266][ T9492] handle_bug+0xce/0x200
[ 43.995757][ T9492] exc_invalid_op+0x1a/0x50
[ 43.996197][ T9492] asm_exc_invalid_op+0x1a/0x20
[ 43.996669][ T9492] RIP: 0010:kobject_add_internal+0x141/0xd00
[ 43.997212][ T9492] Code: e9 da 00 00 00 e8 ff 0f 03 f6 b8 fe ff ff
ff e9 0a 07 00 00 e8 f0 0f 03 f6 eb 05 e8 e9 0f 03 f6 48 8d 3d 72 80
a4 04 48 89 de <67> 48 0f b9 3a b8 ea ff ff ff e9 e5 06 00 00 4c 8d 73
20 4d 89 f5
[ 43.998921][ T9492] RSP: 0018:ffffc90007b5f2d8 EFLAGS: 00010293
[ 43.999474][ T9492] RAX: ffffffff8bc48c97 RBX: ffff888107e94000
RCX: ffff88802e21a640
[ 44.000182][ T9492] RDX: 0000000000000000 RSI: ffff888107e94000
RDI: ffffffff90690d10
[ 44.000887][ T9492] RBP: 0000000000000000 R08: ffffc90007b5f3b7
R09: 0000000000000000
[ 44.001595][ T9492] R10: ffffc90007b5f3a0 R11: fffff52000f6be77
R12: 1ffff11020fd2800
[ 44.002304][ T9492] R13: dffffc0000000000 R14: ffff8881054a19e0
R15: dffffc0000000000
[ 44.003015][ T9492] ? kobject_add_internal+0x137/0xd00
[ 44.003502][ T9492] ? kobject_add_internal+0x137/0xd00
[ 44.004008][ T9492] kobject_add+0x163/0x240
[ 44.004418][ T9492] ? __pfx_kobject_add+0x10/0x10
[ 44.004870][ T9492] ? bus_get_dev_root+0x127/0x160
[ 44.005335][ T9492] ? get_device_parent+0x38c/0x3a0
[ 44.005847][ T9492] ? __pfx_klist_children_get+0x10/0x10
[ 44.006414][ T9492] device_add+0x408/0xb90
[ 44.006842][ T9492] vdpasim_blk_dev_add+0x1e2/0x2a0
[ 44.007371][ T9492] ? __pfx_vdpasim_blk_dev_add+0x10/0x10
[ 44.007884][ T9492] ? __pfx_vdpasim_blk_work+0x10/0x10
[ 44.008372][ T9492] ? __pfx_vdpasim_blk_get_config+0x10/0x10
[ 44.008908][ T9492] ? __pfx_vdpasim_blk_free+0x10/0x10
[ 44.009429][ T9492] ? vdpa_mgmtdev_get_from_attr+0x2bb/0x2d0
[ 44.009995][ T9492] vdpa_nl_cmd_dev_add_set_doit+0xa75/0xbc0
[ 44.010576][ T9492] ? __pfx_vdpa_nl_cmd_dev_add_set_doit+0x10/0x10
[ 44.011154][ T9492] ? __nla_parse+0x40/0x60
[ 44.011566][ T9492] ? genl_family_rcv_msg_attrs_parse+0x20b/0x2f0
[ 44.012144][ T9492] ? genl_family_rcv_msg_attrs_parse+0x265/0x2f0
[ 44.012717][ T9492] genl_family_rcv_msg_doit+0x22a/0x330
[ 44.013221][ T9492] ? __asan_memcpy+0x40/0x70
[ 44.013647][ T9492] ? __pfx_genl_family_rcv_msg_doit+0x10/0x10
[ 44.014204][ T9492] ? bpf_lsm_capable+0x9/0x20
[ 44.014634][ T9492] ? security_capable+0x7e/0x2c0
[ 44.015096][ T9492] genl_rcv_msg+0x61c/0x7a0
[ 44.015582][ T9492] ? __pfx_genl_rcv_msg+0x10/0x10
[ 44.016045][ T9492] ? __pfx_vdpa_nl_cmd_dev_add_set_doit+0x10/0x10
[ 44.016625][ T9492] netlink_rcv_skb+0x232/0x4b0
[ 44.017069][ T9492] ? __pfx_genl_rcv_msg+0x10/0x10
[ 44.017527][ T9492] ? __pfx_netlink_rcv_skb+0x10/0x10
[ 44.018015][ T9492] ? down_read+0x2be/0x330
[ 44.018423][ T9492] genl_rcv+0x28/0x40
[ 44.018791][ T9492] netlink_unicast+0x75e/0x8e0
[ 44.019235][ T9492] netlink_sendmsg+0x813/0xb40
[ 44.019675][ T9492] ? __pfx_netlink_sendmsg+0x10/0x10
[ 44.020177][ T9492] ? apparmor_socket_sendmsg+0x95/0x390
[ 44.020695][ T9492] ? __pfx_netlink_sendmsg+0x10/0x10
[ 44.021176][ T9492] sock_sendmsg_nosec+0x13a/0x180
[ 44.021635][ T9492] __sys_sendto+0x408/0x5a0
[ 44.022059][ T9492] ? __pfx___sys_sendto+0x10/0x10
[ 44.022525][ T9492] ? fd_install+0x94/0x3d0
[ 44.022934][ T9492] ? fd_install+0x309/0x3d0
[ 44.023352][ T9492] __x64_sys_sendto+0xde/0x100
[ 44.023791][ T9492] do_syscall_64+0x155/0x510
[ 44.024218][ T9492] ? trace_irq_disable+0x3b/0x140
[ 44.024676][ T9492] ? entry_SYSCALL_64_after_hwframe+0x77/0x7f
[ 44.025227][ T9492] ? clear_bhb_loop+0x30/0x80
[ 44.025725][ T9492] entry_SYSCALL_64_after_hwframe+0x77/0x7f
[ 44.026262][ T9492] RIP: 0033:0x42ce46
[ 44.026621][ T9492] Code: 47 ba 04 00 00 00 48 c7 c0 f0 ff ff ff 64
89 10 48 c7 c2 ff ff ff ff c9 48 89 d0 c3 0f 1f 84 00 00 00 00 00 48
8b 45 10 0f 05 <48> 89 c2 48 3d 00 f0 ff ff 77 0f c9 48 89 d0 c3 66 2e
0f 1f 84 00
[ 44.028412][ T9492] RSP: 002b:00007ffc31f8bd20 EFLAGS: 00000202
ORIG_RAX: 000000000000002c
[ 44.029158][ T9492] RAX: ffffffffffffffda RBX: 0000000000000001
RCX: 000000000042ce46
[ 44.029866][ T9492] RDX: 000000000000002c RSI: 00007ffc31f8bda0
RDI: 0000000000000003
[ 44.030576][ T9492] RBP: 00007ffc31f8bd30 R08: 00007ffc31f8bd94
R09: 000000000000000c
[ 44.031283][ T9492] R10: 0000000000000000 R11: 0000000000000202
R12: 00007ffc31f8c208
[ 44.031993][ T9492] R13: 00007ffc31f8c218 R14: 0000000000000002
R15: 00000000004ad140
[ 44.032708][ T9492] </TASK>
[ 44.033595][ T9492] Kernel Offset: disabled
[ 44.034143][ T9492] Rebooting in 86400 seconds..
Regards,
Attachment:
reproducer.c
Description: Binary data