Re: [PATCH] hw/display/virtio-gpu: Initialize blob mapping for ATTACH_BACKING

On 2026/07/28 6:36, Michael Tokarev wrote:
> On 7/25/26 10:11, Akihiko Odaki wrote:
>> It is necessary for blob cursor and scanout.
>>
>> Fixes: e0933d91b1cd ("virtio-gpu: Add virtio_gpu_resource_create_blob")
>> Signed-off-by: Akihiko Odaki <[email protected]>
>> ---
>>   hw/display/virtio-gpu.c | 4 ++++
>>   1 file changed, 4 insertions(+)
> 
> Again, is this a qemu-stable material?  From the description
> it's difficult to say what's going on here, it feels like this
> change should be back-ported to the stable branches.

This is another[1] NULL pointer derefence fix; it is a trivial fix that 
can be cleanly backported.

[1] 
https://lore.kernel.org/qemu-devel/[email protected]/

Regards,
Akihiko Odaki

> 
> Thanks,
> 
> /mjt
> 
>> diff --git a/hw/display/virtio-gpu.c b/hw/display/virtio-gpu.c
>> index 718ba3039290..e886298ec42f 100644
>> --- a/hw/display/virtio-gpu.c
>> +++ b/hw/display/virtio-gpu.c
>> @@ -984,6 +984,10 @@ virtio_gpu_resource_attach_backing(VirtIOGPU *g,
>>           cmd->error = VIRTIO_GPU_RESP_ERR_UNSPEC;
>>           return;
>>       }
>> +
>> +    if (!res->image) {
>> +        virtio_gpu_init_udmabuf(res);
>> +    }
>>   }
>>   static void
>>
>> ---
>> base-commit: 006a22cb26998998385b104db1ff9466ef2f3153
>> change-id: 20260725-backing-db0e69515455
>>
>> Best regards,
>> -- 
>> Akihiko Odaki <[email protected]>
>>
>>
>