[Qemu-devel] device_del fail

[Qemu-devel] device_del fail

[Lying]

Hello everybody, I encounter a error on my vm guest
I remove my device on my guest is failed, following is detail message.
I didn't add my audio device before running my guest, So i add audio with "device_add" after running
Then i can use it, so i remove it with "device_del", but when i do it again, i can't use my audio device and cannot remove it.

Re: [Qemu-devel] device_del fail

[Fam Zheng]

On Wed, 11/29 13:43, Lying wrote:
> Hello everybody, I encounter a error on my vm guest
> I remove my device on my guest is failed, following is detail message.
> I didn't add my audio device before running my guest, So i add audio with "device_add" after running
> Then i can use it, so i remove it with "device_del", but when i do it again, i
> can't use my audio device and cannot remove it.


I haven't tried unplugging an audio device myself but in general PCI hot unplug
needs guest cooperation so some infomation about guest is also helpful.  Which
guest OS is this?

What are the exact commands that you used and what are the messages from
host/guest when you device_del?

Fam

Re: [Qemu-devel] device_del fail

[Fam Zheng]

Let's keep qemu-devel@nongnu.org on the list so other people can chime in.

On Thu, 11/30 10:05, Lying wrote:
 
> At 2017-11-29 14:29:17, "Fam Zheng" <famz@redhat.com> wrote:
> >On Wed, 11/29 13:43, Lying wrote:
> >> Hello everybody, I encounter a error on my vm guest
> >> I remove my device on my guest is failed, following is detail message.
> >> I didn't add my audio device before running my guest, So i add audio with "device_add" after running
> >> Then i can use it, so i remove it with "device_del", but when i do it again, i
> >> can't use my audio device and cannot remove it.
> >
> >
> >I haven't tried unplugging an audio device myself but in general PCI hot unplug
> >needs guest cooperation so some infomation about guest is also helpful.  Which
> >guest OS is this?
> >
> >What are the exact commands that you used and what are the messages from
> >host/guest when you device_del?
> >
> 
> >Fam
> 
> 
> hello, thanks for your reply, and i'm sorry that i not notice at yesterday .
> following is my information:
>     guest : window-7
>     host : Ubuntu-16.04
>     qemu : 2.11.0-rc0
>     libvirt : 3.9
>    seabios : 1.10.74 (from qemu)
> exact commands:
>     add:"device_add driver=vfio-pci,host=02:00.0,x-vga=on,multifunction=yes,id=gpu1"
>     remove:"device_del gpu1"
> and not messages when i running device_del. But i can see it still exist while running commands "info pci"

Probably the guest didn't respond to the hot-unplug event. In your original
question you said it is an audio device but your command suggests it is a GPU
device. I'm not sure Windows driver can handle this. Have you tried different
guests, such as Linux?

Cc Alex who may know more.

Fam

Re: [Qemu-devel] device_del fail

[Lying]

hello, i try again on arch Linux , after i add gpu, display is not light,following message from "info pci":
  Bus  0, device   5, function 0:
    VGA controller: PCI device 10de:1401
      IRQ 11.
      BAR0: 32 bit memory at 0xffffffffffffffff [0x00fffffe].
      BAR1: 64 bit prefetchable memory at 0xffffffffffffffff [0x0ffffffe].
      BAR3: 64 bit prefetchable memory at 0xffffffffffffffff [0x01fffffe].
      BAR5: I/O at 0xffffffffffffffff [0x007e].
      BAR6: 32 bit memory at 0xffffffffffffffff [0x0001fffe].
      id "gpu1"
  Bus  0, device   6, function 0:
    Audio controller: PCI device 10de:0fba
      IRQ 10.
      BAR0: 32 bit memory at 0x3e820000 [0x3e823fff].
      id "gpu2"


Then i connect that guest with ssh:
Last login: Thu Nov 30 22:29:03 2017(it's normal)




At 2017-11-30 10:32:26, "Fam Zheng" <famz@redhat.com> wrote:
>Let's keep qemu-devel@nongnu.org on the list so other people can chime in.
>
>On Thu, 11/30 10:05, Lying wrote:
> 
>> At 2017-11-29 14:29:17, "Fam Zheng" <famz@redhat.com> wrote:
>> >On Wed, 11/29 13:43, Lying wrote:
>> >> Hello everybody, I encounter a error on my vm guest
>> >> I remove my device on my guest is failed, following is detail message.
>> >> I didn't add my audio device before running my guest, So i add audio with "device_add" after running
>> >> Then i can use it, so i remove it with "device_del", but when i do it again, i
>> >> can't use my audio device and cannot remove it.
>> >
>> >
>> >I haven't tried unplugging an audio device myself but in general PCI hot unplug
>> >needs guest cooperation so some infomation about guest is also helpful.  Which
>> >guest OS is this?
>> >
>> >What are the exact commands that you used and what are the messages from
>> >host/guest when you device_del?
>> >
>> 
>> >Fam
>> 
>> 
>> hello, thanks for your reply, and i'm sorry that i not notice at yesterday .
>> following is my information:
>>     guest : window-7
>>     host : Ubuntu-16.04
>>     qemu : 2.11.0-rc0
>>     libvirt : 3.9
>>    seabios : 1.10.74 (from qemu)
>> exact commands:
>>     add:"device_add driver=vfio-pci,host=02:00.0,x-vga=on,multifunction=yes,id=gpu1"
>>     remove:"device_del gpu1"
>> and not messages when i running device_del. But i can see it still exist while running commands "info pci"
>
>Probably the guest didn't respond to the hot-unplug event. In your original
>question you said it is an audio device but your command suggests it is a GPU
>device. I'm not sure Windows driver can handle this. Have you tried different
>guests, such as Linux?
>
>Cc Alex who may know more.
>
>Fam