Re: git: 1ea0721e1a56 - main - vtgpu: Support virtio gpu on Parallels Desktop

On 2/10/26 09:07, Andrew Turner wrote:
> The branch main has been updated by andrew:
> 
> URL: https://cgit.FreeBSD.org/src/commit/?id=1ea0721e1a566fdb552b0a919c22667844a894d9
> 
> commit 1ea0721e1a566fdb552b0a919c22667844a894d9
> Author:     Andrew Turner <andrew@FreeBSD.org>
> AuthorDate: 2026-02-10 17:06:31 +0000
> Commit:     Andrew Turner <andrew@FreeBSD.org>
> CommitDate: 2026-02-10 17:06:31 +0000
> 
>     vtgpu: Support virtio gpu on Parallels Desktop
>     
>     The Parallels Desktop Virtio GPU implementation doesn't handle
>     enqueuing the VIRTIO_GPU_CMD_RESOURCE_ATTACH_BACKING request and
>     memory list together.
>     
>     Work around this by splitting them before sending them to be enqueued.
>     
>     Sponsored by:   Arm Ltd
>     Differential Revision:  https://reviews.freebsd.org/D55147
> ---
>  sys/dev/virtio/gpu/virtio_gpu.c | 51 ++++++++++++++++++++++++++++++-----------
>  1 file changed, 38 insertions(+), 13 deletions(-)
> 
> diff --git a/sys/dev/virtio/gpu/virtio_gpu.c b/sys/dev/virtio/gpu/virtio_gpu.c
> index 668eb170304a..b95bae9fe286 100644
> --- a/sys/dev/virtio/gpu/virtio_gpu.c
> +++ b/sys/dev/virtio/gpu/virtio_gpu.c
> @@ -445,21 +445,33 @@ vtgpu_alloc_virtqueue(struct vtgpu_softc *sc)
>  }
>  
>  static int
> -vtgpu_req_resp(struct vtgpu_softc *sc, void *req, size_t reqlen,
> -    void *resp, size_t resplen)
> +vtgpu_req_resp2(struct vtgpu_softc *sc, void *req1, size_t req1len,
> +    void *req2, size_t req2len, void *resp, size_t resplen)
>  {
>  	struct sglist sg;
> -	struct sglist_seg segs[2];
> -	int error;
> +	struct sglist_seg segs[3];
> +	int error, rcount;
>  
> -	sglist_init(&sg, 2, segs);
> +	sglist_init(&sg, 3, segs);
>  
> -	error = sglist_append(&sg, req, reqlen);
> +	rcount = 1;
> +	error = sglist_append(&sg, req1, req1len);
>  	if (error != 0) {
>  		device_printf(sc->vtgpu_dev,
> -		    "Unable to append the request to the sglist: %d\n", error);
> +		    "Unable to append the request to the sglist: %d\n",
> +		    error);
>  		return (error);
>  	}
> +	if (req2 != NULL) {
> +		error = sglist_append(&sg, req2, req2len);
> +		if (error != 0) {
> +			device_printf(sc->vtgpu_dev,
> +			    "Unable to append the request to the sglist: %d\n",
> +			    error);
> +			return (error);
> +		}
> +		rcount++;
> +	}
>  	error = sglist_append(&sg, resp, resplen);
>  	if (error != 0) {
>  		device_printf(sc->vtgpu_dev,
> @@ -467,7 +479,7 @@ vtgpu_req_resp(struct vtgpu_softc *sc, void *req, size_t reqlen,
>  		    error);
>  		return (error);
>  	}
> -	error = virtqueue_enqueue(sc->vtgpu_ctrl_vq, resp, &sg, 1, 1);
> +	error = virtqueue_enqueue(sc->vtgpu_ctrl_vq, resp, &sg, rcount, 1);
>  	if (error != 0) {
>  		device_printf(sc->vtgpu_dev, "Enqueue failed: %d\n", error);
>  		return (error);
> @@ -479,6 +491,13 @@ vtgpu_req_resp(struct vtgpu_softc *sc, void *req, size_t reqlen,
>  	return (0);
>  }
>  
> +static int
> +vtgpu_req_resp(struct vtgpu_softc *sc, void *req, size_t reqlen,
> +    void *resp, size_t resplen)
> +{
> +	return (vtgpu_req_resp2(sc, req, reqlen, NULL, 0, resp, resplen));
> +}
> +
>  static int
>  vtgpu_get_display_info(struct vtgpu_softc *sc)
>  {
> @@ -559,9 +578,15 @@ static int
>  vtgpu_attach_backing(struct vtgpu_softc *sc)
>  {
>  	struct {
> +		/*
> +		 * Split the backing and mem request arguments as some
> +		 * hypervisors, e.g. Parallels Desktop, don't work when
> +		 * they are enqueued together.
> +		 */
>  		struct {
>  			struct virtio_gpu_resource_attach_backing backing;
> -			struct virtio_gpu_mem_entry mem[1];
> +			char pad;
> +			struct virtio_gpu_mem_entry mem;
>  		} req;
>  		char pad;
>  		struct virtio_gpu_ctrl_hdr resp;
> @@ -577,11 +602,11 @@ vtgpu_attach_backing(struct vtgpu_softc *sc)
>  	s.req.backing.resource_id = htole32(VTGPU_RESOURCE_ID);
>  	s.req.backing.nr_entries = htole32(1);
>  
> -	s.req.mem[0].addr = htole64(sc->vtgpu_fb_info.fb_pbase);
> -	s.req.mem[0].length = htole32(sc->vtgpu_fb_info.fb_size);
> +	s.req.mem.addr = htole64(sc->vtgpu_fb_info.fb_pbase);
> +	s.req.mem.length = htole32(sc->vtgpu_fb_info.fb_size);
>  
> -	error = vtgpu_req_resp(sc, &s.req, sizeof(s.req), &s.resp,
> -	    sizeof(s.resp));
> +	error = vtgpu_req_resp2(sc, &s.req.backing, sizeof(s.req.backing),
> +	    &s.req.mem, sizeof(s.req.mem), &s.resp, sizeof(s.resp));
>  	if (error != 0)
>  		return (error);
>  
> 
> 

Up to now, for the aarch64 macOS context, I've been using the below
/boot/device.hints to only get the console that results from the change.
since virtio_pci1 was not working. That has been sufficient for my
context: Mostly I ssh in and do not use the console for much. (The long
"virtio_pci1:" comment line below will wrap twice.)

# cat /boot/device.hints
# This is for virtio_gpu --for avoiding its use under Parallels:
# dmesg -a | grep -i "virtio.*gpu"
# virtio_pci1: <VirtIO PCI (modern) GPU adapter> mem
0x10000000-0x17ffffff,0x18008000-0x18008fff,0x18000000-0x18003fff at
device 10.0 on pci0
hint.virtio_pci.1.disabled="1"

Should the change committed mean that things would likely work if I then
comment out the hint.virtio_pci.1.disabled assignment (once I manage to
upgrade)?


-- 
===
Mark Millard
marklmi at yahoo.com