CLI -netdev accumulates in option group "netdev".
Before commit 08712fcb85 "net: Track netdevs in NetClientState rather
than QemuOpt", netdev_add added to the option group, and netdev_del
removed from it, both HMP and QMP. Thus, every netdev had a
corresponding QemuOpts in this option group.
Commit 08712fcb85 dropped this for QMP netdev_add and both netdev_del.
Now a netdev has a corresponding QemuOpts only when it was created
with CLI or HMP. Two issues:
* QMP and HMP netdev_del can leave QemuOpts behind, breaking HMP
netdev_add. Reproducer:
$ qemu-system-x86_64 -S -display none -nodefaults -monitor stdio
QEMU 5.1.92 monitor - type 'help' for more information
(qemu) netdev_add user,id=net0
(qemu) info network
net0: index=0,type=user,net=10.0.2.0,restrict=off
(qemu) netdev_del net0
(qemu) info network
(qemu) netdev_add user,id=net0
upstream-qemu: Duplicate ID 'net0' for netdev
Try "help netdev_add" for more information
Fix by restoring the QemuOpts deletion in qmp_netdev_del(), but with
a guard, because the QemuOpts need not exist.
* QMP netdev_add loses its "no duplicate ID" check. Reproducer:
$ qemu-system-x86_64 -S -display none -qmp stdio
{"QMP": {"version": {"qemu": {"micro": 92, "minor": 1, "major": 5}, "package": "v5.2.0-rc2-1-g02c1f0142c"}, "capabilities": ["oob"]}}
{"execute": "qmp_capabilities"}
{"return": {}}
{"execute": "netdev_add", "arguments": {"type": "user", "id":"net0"}}
{"return": {}}
{"execute": "netdev_add", "arguments": {"type": "user", "id":"net0"}}
{"return": {}}
Fix by adding a duplicate ID check to net_client_init1() to replace
the lost one. The check is redundant for callers where QemuOpts
still checks, i.e. for CLI and HMP.
Reported-by: Andrew Melnichenko <andrew@daynix.com>
Fixes: 08712fcb85
Cc: qemu-stable@nongnu.org
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
831734cce6