| Message ID | 965a31ed0c51f30c4e3a3a9df5db9c4892ec914e.1405416206.git.amit.shah@redhat.com |
|---|---|
| State | New |
| Headers | show |
Il 15/07/2014 11:23, Amit Shah ha scritto: > i = port_id / 32; This can also be moved inside the if. Paolo > - vser->ports_map[i] &= ~(1U << (port_id % 32)); > + if (port_id) { > + /* > + * Don't mark port 0 removed -- we explicitly reserve it for > + * backward compat with older guests, and a device unplug of > + * virtconsole removes the reservation. > + */ > + vser->ports_map[i] &= ~(1U << (port_id % 32)); > + }
diff --git a/hw/char/virtio-serial-bus.c b/hw/char/virtio-serial-bus.c index 07bebc0..e1808b0 100644 --- a/hw/char/virtio-serial-bus.c +++ b/hw/char/virtio-serial-bus.c @@ -800,7 +800,14 @@ static void remove_port(VirtIOSerial *vser, uint32_t port_id) unsigned int i; i = port_id / 32; - vser->ports_map[i] &= ~(1U << (port_id % 32)); + if (port_id) { + /* + * Don't mark port 0 removed -- we explicitly reserve it for + * backward compat with older guests, and a device unplug of + * virtconsole removes the reservation. + */ + vser->ports_map[i] &= ~(1U << (port_id % 32)); + } port = find_port_by_id(vser, port_id); /*
We keep port 0 reserved for compat with older guests, where only virtio-console was expected. Even if a system is started without a virtio-console port, port #0 is kept aside. However, after a virtconsole port is unplugged, port id 0 became available, and the next hotplug of a virtserialport caused failure due to it not being a console port. Steps to reproduce: $ ./x86_64-softmmu/qemu-system-x86_64 -m 512 -cpu host -enable-kvm -device virtio-serial-pci -monitor stdio -vnc :1 QEMU 2.0.91 monitor - type 'help' for more information (qemu) device_add virtconsole,id=p1 (qemu) device_del p1 (qemu) device_add virtserialport,id=p1 Port number 0 on virtio-serial devices reserved for virtconsole devices for backward compatibility. Device 'virtserialport' could not be initialized (qemu) quit Reported-by: dengmin <mdeng@redhat.com> Signed-off-by: Amit Shah <amit.shah@redhat.com> --- hw/char/virtio-serial-bus.c | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-)