2021-09-14 00:52:42

by Dexuan Cui

[permalink] [raw]
Subject: [PATCH] drm/hyperv: Fix double mouse pointers

It looks like Hyper-V supports a hardware cursor feature. It is not used
by Linux VM, but the Hyper-V host still draws a point as an extra mouse
pointer, which is unwanted, especially when Xorg is running.

The hyperv_fb driver uses synthvid_send_ptr() to hide the unwanted pointer.
When the hyperv_drm driver was developed, the function synthvid_send_ptr()
was not copied from the hyperv_fb driver. Fix the issue by adding the
function into hyperv_drm.

Fixes: 76c56a5affeb ("drm/hyperv: Add DRM driver for hyperv synthetic video device")
Signed-off-by: Dexuan Cui <[email protected]>
Cc: Deepak Rawat <[email protected]>
Cc: Haiyang Zhang <[email protected]>
---
drivers/gpu/drm/hyperv/hyperv_drm.h | 1 +
drivers/gpu/drm/hyperv/hyperv_drm_modeset.c | 1 +
drivers/gpu/drm/hyperv/hyperv_drm_proto.c | 39 ++++++++++++++++++++-
3 files changed, 40 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/hyperv/hyperv_drm.h b/drivers/gpu/drm/hyperv/hyperv_drm.h
index 886add4f9cd0..27bfd27c05be 100644
--- a/drivers/gpu/drm/hyperv/hyperv_drm.h
+++ b/drivers/gpu/drm/hyperv/hyperv_drm.h
@@ -46,6 +46,7 @@ int hyperv_mode_config_init(struct hyperv_drm_device *hv);
int hyperv_update_vram_location(struct hv_device *hdev, phys_addr_t vram_pp);
int hyperv_update_situation(struct hv_device *hdev, u8 active, u32 bpp,
u32 w, u32 h, u32 pitch);
+int hyperv_send_ptr(struct hv_device *hdev);
int hyperv_update_dirt(struct hv_device *hdev, struct drm_rect *rect);
int hyperv_connect_vsp(struct hv_device *hdev);

diff --git a/drivers/gpu/drm/hyperv/hyperv_drm_modeset.c b/drivers/gpu/drm/hyperv/hyperv_drm_modeset.c
index 3aaee4730ec6..e21c82cf3326 100644
--- a/drivers/gpu/drm/hyperv/hyperv_drm_modeset.c
+++ b/drivers/gpu/drm/hyperv/hyperv_drm_modeset.c
@@ -101,6 +101,7 @@ static void hyperv_pipe_enable(struct drm_simple_display_pipe *pipe,
struct hyperv_drm_device *hv = to_hv(pipe->crtc.dev);
struct drm_shadow_plane_state *shadow_plane_state = to_drm_shadow_plane_state(plane_state);

+ hyperv_send_ptr(hv->hdev);
hyperv_update_situation(hv->hdev, 1, hv->screen_depth,
crtc_state->mode.hdisplay,
crtc_state->mode.vdisplay,
diff --git a/drivers/gpu/drm/hyperv/hyperv_drm_proto.c b/drivers/gpu/drm/hyperv/hyperv_drm_proto.c
index 6d4bdccfbd1a..1ea7a0432320 100644
--- a/drivers/gpu/drm/hyperv/hyperv_drm_proto.c
+++ b/drivers/gpu/drm/hyperv/hyperv_drm_proto.c
@@ -299,6 +299,40 @@ int hyperv_update_situation(struct hv_device *hdev, u8 active, u32 bpp,
return 0;
}

+/* Send mouse pointer info to host */
+int hyperv_send_ptr(struct hv_device *hdev)
+{
+ struct synthvid_msg msg;
+
+ memset(&msg, 0, sizeof(struct synthvid_msg));
+ msg.vid_hdr.type = SYNTHVID_POINTER_POSITION;
+ msg.vid_hdr.size = sizeof(struct synthvid_msg_hdr) +
+ sizeof(struct synthvid_pointer_position);
+ msg.ptr_pos.is_visible = 1;
+ msg.ptr_pos.video_output = 0;
+ msg.ptr_pos.image_x = 0;
+ msg.ptr_pos.image_y = 0;
+ hyperv_sendpacket(hdev, &msg);
+
+ memset(&msg, 0, sizeof(struct synthvid_msg));
+ msg.vid_hdr.type = SYNTHVID_POINTER_SHAPE;
+ msg.vid_hdr.size = sizeof(struct synthvid_msg_hdr) +
+ sizeof(struct synthvid_pointer_shape);
+ msg.ptr_shape.part_idx = SYNTHVID_CURSOR_COMPLETE;
+ msg.ptr_shape.is_argb = 1;
+ msg.ptr_shape.width = 1;
+ msg.ptr_shape.height = 1;
+ msg.ptr_shape.hot_x = 0;
+ msg.ptr_shape.hot_y = 0;
+ msg.ptr_shape.data[0] = 0;
+ msg.ptr_shape.data[1] = 1;
+ msg.ptr_shape.data[2] = 1;
+ msg.ptr_shape.data[3] = 1;
+ hyperv_sendpacket(hdev, &msg);
+
+ return 0;
+}
+
int hyperv_update_dirt(struct hv_device *hdev, struct drm_rect *rect)
{
struct hyperv_drm_device *hv = hv_get_drvdata(hdev);
@@ -392,8 +426,11 @@ static void hyperv_receive_sub(struct hv_device *hdev)
return;
}

- if (msg->vid_hdr.type == SYNTHVID_FEATURE_CHANGE)
+ if (msg->vid_hdr.type == SYNTHVID_FEATURE_CHANGE) {
hv->dirt_needed = msg->feature_chg.is_dirt_needed;
+ if (hv->dirt_needed)
+ hyperv_send_ptr(hv->hdev);
+ }
}

static void hyperv_receive(void *ctx)
--
2.25.1


2021-09-14 01:00:15

by Haiyang Zhang

[permalink] [raw]
Subject: RE: [PATCH] drm/hyperv: Fix double mouse pointers



> -----Original Message-----
> From: Dexuan Cui <[email protected]>
> Sent: Monday, September 13, 2021 2:27 PM
> To: [email protected]; Haiyang Zhang <[email protected]>;
> [email protected]; [email protected]; [email protected]; dri-
> [email protected]
> Cc: [email protected]; [email protected]; Dexuan
> Cui <[email protected]>
> Subject: [PATCH] drm/hyperv: Fix double mouse pointers
>
> It looks like Hyper-V supports a hardware cursor feature. It is not used
> by Linux VM, but the Hyper-V host still draws a point as an extra mouse
> pointer, which is unwanted, especially when Xorg is running.
>
> The hyperv_fb driver uses synthvid_send_ptr() to hide the unwanted
> pointer.
> When the hyperv_drm driver was developed, the function
> synthvid_send_ptr()
> was not copied from the hyperv_fb driver. Fix the issue by adding the
> function into hyperv_drm.
>
> Fixes: 76c56a5affeb ("drm/hyperv: Add DRM driver for hyperv synthetic
> video device")
> Signed-off-by: Dexuan Cui <[email protected]>
> Cc: Deepak Rawat <[email protected]>
> Cc: Haiyang Zhang <[email protected]>
> ---
> drivers/gpu/drm/hyperv/hyperv_drm.h | 1 +
> drivers/gpu/drm/hyperv/hyperv_drm_modeset.c | 1 +
> drivers/gpu/drm/hyperv/hyperv_drm_proto.c | 39 ++++++++++++++++++++-
> 3 files changed, 40 insertions(+), 1 deletion(-)

Thank you!
Reviewed-by: Haiyang Zhang <[email protected]>

2021-09-14 16:01:48

by Deepak Rawat

[permalink] [raw]
Subject: Re: [PATCH] drm/hyperv: Fix double mouse pointers

Thanks Dexuan, for the patch. A minor comment below.

On Mon, Sep 13, 2021 at 11:27 AM Dexuan Cui <[email protected]> wrote:
>
> It looks like Hyper-V supports a hardware cursor feature. It is not used
> by Linux VM, but the Hyper-V host still draws a point as an extra mouse
> pointer, which is unwanted, especially when Xorg is running.
>
> The hyperv_fb driver uses synthvid_send_ptr() to hide the unwanted pointer.
> When the hyperv_drm driver was developed, the function synthvid_send_ptr()
> was not copied from the hyperv_fb driver. Fix the issue by adding the
> function into hyperv_drm.
>
> Fixes: 76c56a5affeb ("drm/hyperv: Add DRM driver for hyperv synthetic video device")
> Signed-off-by: Dexuan Cui <[email protected]>
> Cc: Deepak Rawat <[email protected]>
> Cc: Haiyang Zhang <[email protected]>
> ---
> drivers/gpu/drm/hyperv/hyperv_drm.h | 1 +
> drivers/gpu/drm/hyperv/hyperv_drm_modeset.c | 1 +
> drivers/gpu/drm/hyperv/hyperv_drm_proto.c | 39 ++++++++++++++++++++-
> 3 files changed, 40 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/gpu/drm/hyperv/hyperv_drm.h b/drivers/gpu/drm/hyperv/hyperv_drm.h
> index 886add4f9cd0..27bfd27c05be 100644
> --- a/drivers/gpu/drm/hyperv/hyperv_drm.h
> +++ b/drivers/gpu/drm/hyperv/hyperv_drm.h
> @@ -46,6 +46,7 @@ int hyperv_mode_config_init(struct hyperv_drm_device *hv);
> int hyperv_update_vram_location(struct hv_device *hdev, phys_addr_t vram_pp);
> int hyperv_update_situation(struct hv_device *hdev, u8 active, u32 bpp,
> u32 w, u32 h, u32 pitch);
> +int hyperv_send_ptr(struct hv_device *hdev);
> int hyperv_update_dirt(struct hv_device *hdev, struct drm_rect *rect);
> int hyperv_connect_vsp(struct hv_device *hdev);
>
> diff --git a/drivers/gpu/drm/hyperv/hyperv_drm_modeset.c b/drivers/gpu/drm/hyperv/hyperv_drm_modeset.c
> index 3aaee4730ec6..e21c82cf3326 100644
> --- a/drivers/gpu/drm/hyperv/hyperv_drm_modeset.c
> +++ b/drivers/gpu/drm/hyperv/hyperv_drm_modeset.c
> @@ -101,6 +101,7 @@ static void hyperv_pipe_enable(struct drm_simple_display_pipe *pipe,
> struct hyperv_drm_device *hv = to_hv(pipe->crtc.dev);
> struct drm_shadow_plane_state *shadow_plane_state = to_drm_shadow_plane_state(plane_state);
>
> + hyperv_send_ptr(hv->hdev);
> hyperv_update_situation(hv->hdev, 1, hv->screen_depth,
> crtc_state->mode.hdisplay,
> crtc_state->mode.vdisplay,
> diff --git a/drivers/gpu/drm/hyperv/hyperv_drm_proto.c b/drivers/gpu/drm/hyperv/hyperv_drm_proto.c
> index 6d4bdccfbd1a..1ea7a0432320 100644
> --- a/drivers/gpu/drm/hyperv/hyperv_drm_proto.c
> +++ b/drivers/gpu/drm/hyperv/hyperv_drm_proto.c
> @@ -299,6 +299,40 @@ int hyperv_update_situation(struct hv_device *hdev, u8 active, u32 bpp,
> return 0;
> }
>
> +/* Send mouse pointer info to host */
> +int hyperv_send_ptr(struct hv_device *hdev)
> +{
> + struct synthvid_msg msg;
> +
> + memset(&msg, 0, sizeof(struct synthvid_msg));
> + msg.vid_hdr.type = SYNTHVID_POINTER_POSITION;
> + msg.vid_hdr.size = sizeof(struct synthvid_msg_hdr) +
> + sizeof(struct synthvid_pointer_position);
> + msg.ptr_pos.is_visible = 1;

"is_visible" should be 0 since you want to hide the pointer. Maybe
better, accept these from the caller.

> + msg.ptr_pos.video_output = 0;
> + msg.ptr_pos.image_x = 0;
> + msg.ptr_pos.image_y = 0;
> + hyperv_sendpacket(hdev, &msg);
> +
> + memset(&msg, 0, sizeof(struct synthvid_msg));
> + msg.vid_hdr.type = SYNTHVID_POINTER_SHAPE;
> + msg.vid_hdr.size = sizeof(struct synthvid_msg_hdr) +
> + sizeof(struct synthvid_pointer_shape);
> + msg.ptr_shape.part_idx = SYNTHVID_CURSOR_COMPLETE;
> + msg.ptr_shape.is_argb = 1;
> + msg.ptr_shape.width = 1;
> + msg.ptr_shape.height = 1;
> + msg.ptr_shape.hot_x = 0;
> + msg.ptr_shape.hot_y = 0;
> + msg.ptr_shape.data[0] = 0;
> + msg.ptr_shape.data[1] = 1;
> + msg.ptr_shape.data[2] = 1;
> + msg.ptr_shape.data[3] = 1;
> + hyperv_sendpacket(hdev, &msg);
> +

Is it necessary to send SYNTHVID_POINTER_SHAPE here? Perhaps we should
separate SYNTHVID_POINTER_POSITION and SYNTHVID_POINTER_SHAPE into
different functions.

> + return 0;
> +}
> +
> int hyperv_update_dirt(struct hv_device *hdev, struct drm_rect *rect)
> {
> struct hyperv_drm_device *hv = hv_get_drvdata(hdev);
> @@ -392,8 +426,11 @@ static void hyperv_receive_sub(struct hv_device *hdev)
> return;
> }
>
> - if (msg->vid_hdr.type == SYNTHVID_FEATURE_CHANGE)
> + if (msg->vid_hdr.type == SYNTHVID_FEATURE_CHANGE) {
> hv->dirt_needed = msg->feature_chg.is_dirt_needed;
> + if (hv->dirt_needed)
> + hyperv_send_ptr(hv->hdev);
> + }
> }
>
> static void hyperv_receive(void *ctx)
> --
> 2.25.1
>

2021-09-14 16:09:17

by Haiyang Zhang

[permalink] [raw]
Subject: RE: [PATCH] drm/hyperv: Fix double mouse pointers



> -----Original Message-----
> From: Deepak Rawat <[email protected]>
> Sent: Tuesday, September 14, 2021 11:59 AM
> To: Dexuan Cui <[email protected]>
> Cc: Haiyang Zhang <[email protected]>; David Airlie
> <[email protected]>; Daniel Vetter <[email protected]>; Thomas Zimmermann
> <[email protected]>; [email protected]; linux-
> [email protected]; [email protected]
> Subject: Re: [PATCH] drm/hyperv: Fix double mouse pointers
>
> Thanks Dexuan, for the patch. A minor comment below.
>
> On Mon, Sep 13, 2021 at 11:27 AM Dexuan Cui <[email protected]> wrote:
> >
> > It looks like Hyper-V supports a hardware cursor feature. It is not
> used
> > by Linux VM, but the Hyper-V host still draws a point as an extra
> mouse
> > pointer, which is unwanted, especially when Xorg is running.
> >
> > The hyperv_fb driver uses synthvid_send_ptr() to hide the unwanted
> pointer.
> > When the hyperv_drm driver was developed, the function
> synthvid_send_ptr()
> > was not copied from the hyperv_fb driver. Fix the issue by adding the
> > function into hyperv_drm.
> >
> > Fixes: 76c56a5affeb ("drm/hyperv: Add DRM driver for hyperv synthetic
> video device")
> > Signed-off-by: Dexuan Cui <[email protected]>
> > Cc: Deepak Rawat <[email protected]>
> > Cc: Haiyang Zhang <[email protected]>
> > ---
> > drivers/gpu/drm/hyperv/hyperv_drm.h | 1 +
> > drivers/gpu/drm/hyperv/hyperv_drm_modeset.c | 1 +
> > drivers/gpu/drm/hyperv/hyperv_drm_proto.c | 39
> ++++++++++++++++++++-
> > 3 files changed, 40 insertions(+), 1 deletion(-)
> >
> > diff --git a/drivers/gpu/drm/hyperv/hyperv_drm.h
> b/drivers/gpu/drm/hyperv/hyperv_drm.h
> > index 886add4f9cd0..27bfd27c05be 100644
> > --- a/drivers/gpu/drm/hyperv/hyperv_drm.h
> > +++ b/drivers/gpu/drm/hyperv/hyperv_drm.h
> > @@ -46,6 +46,7 @@ int hyperv_mode_config_init(struct hyperv_drm_device
> *hv);
> > int hyperv_update_vram_location(struct hv_device *hdev, phys_addr_t
> vram_pp);
> > int hyperv_update_situation(struct hv_device *hdev, u8 active, u32
> bpp,
> > u32 w, u32 h, u32 pitch);
> > +int hyperv_send_ptr(struct hv_device *hdev);
> > int hyperv_update_dirt(struct hv_device *hdev, struct drm_rect *rect);
> > int hyperv_connect_vsp(struct hv_device *hdev);
> >
> > diff --git a/drivers/gpu/drm/hyperv/hyperv_drm_modeset.c
> b/drivers/gpu/drm/hyperv/hyperv_drm_modeset.c
> > index 3aaee4730ec6..e21c82cf3326 100644
> > --- a/drivers/gpu/drm/hyperv/hyperv_drm_modeset.c
> > +++ b/drivers/gpu/drm/hyperv/hyperv_drm_modeset.c
> > @@ -101,6 +101,7 @@ static void hyperv_pipe_enable(struct
> drm_simple_display_pipe *pipe,
> > struct hyperv_drm_device *hv = to_hv(pipe->crtc.dev);
> > struct drm_shadow_plane_state *shadow_plane_state =
> to_drm_shadow_plane_state(plane_state);
> >
> > + hyperv_send_ptr(hv->hdev);
> > hyperv_update_situation(hv->hdev, 1, hv->screen_depth,
> > crtc_state->mode.hdisplay,
> > crtc_state->mode.vdisplay,
> > diff --git a/drivers/gpu/drm/hyperv/hyperv_drm_proto.c
> b/drivers/gpu/drm/hyperv/hyperv_drm_proto.c
> > index 6d4bdccfbd1a..1ea7a0432320 100644
> > --- a/drivers/gpu/drm/hyperv/hyperv_drm_proto.c
> > +++ b/drivers/gpu/drm/hyperv/hyperv_drm_proto.c
> > @@ -299,6 +299,40 @@ int hyperv_update_situation(struct hv_device
> *hdev, u8 active, u32 bpp,
> > return 0;
> > }
> >
> > +/* Send mouse pointer info to host */
> > +int hyperv_send_ptr(struct hv_device *hdev)
> > +{
> > + struct synthvid_msg msg;
> > +
> > + memset(&msg, 0, sizeof(struct synthvid_msg));
> > + msg.vid_hdr.type = SYNTHVID_POINTER_POSITION;
> > + msg.vid_hdr.size = sizeof(struct synthvid_msg_hdr) +
> > + sizeof(struct synthvid_pointer_position);
> > + msg.ptr_pos.is_visible = 1;
>
> "is_visible" should be 0 since you want to hide the pointer. Maybe
> better, accept these from the caller.

I believe I tried is_visible = 0 during my implementation of the hyperv_fb. It still have the host cursor visible... So I had to set the cursor color's alpha value = 0 to make it transparent. But you may try is_visible = 0 again.

Thanks,
- Haiyang

2021-09-15 07:00:22

by Dexuan Cui

[permalink] [raw]
Subject: RE: [PATCH] drm/hyperv: Fix double mouse pointers

> From: Deepak Rawat <[email protected]>
> Sent: Tuesday, September 14, 2021 8:59 AM
> ...
> > +/* Send mouse pointer info to host */
> > +int hyperv_send_ptr(struct hv_device *hdev)
> > +{
> > + struct synthvid_msg msg;
> > +
> > + memset(&msg, 0, sizeof(struct synthvid_msg));
> > + msg.vid_hdr.type = SYNTHVID_POINTER_POSITION;
> > + msg.vid_hdr.size = sizeof(struct synthvid_msg_hdr) +
> > + sizeof(struct synthvid_pointer_position);
> > + msg.ptr_pos.is_visible = 1;
>
> "is_visible" should be 0 since you want to hide the pointer. Maybe
> better, accept these from the caller.

According to my test, "is_visible = 0" doesn't work, i.e. can't hide the
unwanted HW mouse poiner. It looks like the field is for some very old
legacy Windows VMs like Windows Vista.

Haiyang also replied in another email, saying "is_visible = 0" doesn't
work.

> > + msg.ptr_pos.video_output = 0;
> > + msg.ptr_pos.image_x = 0;
> > + msg.ptr_pos.image_y = 0;
> > + hyperv_sendpacket(hdev, &msg);
> > +
> > + memset(&msg, 0, sizeof(struct synthvid_msg));
> > + msg.vid_hdr.type = SYNTHVID_POINTER_SHAPE;
> > + msg.vid_hdr.size = sizeof(struct synthvid_msg_hdr) +
> > + sizeof(struct synthvid_pointer_shape);
> > + msg.ptr_shape.part_idx = SYNTHVID_CURSOR_COMPLETE;
> > + msg.ptr_shape.is_argb = 1;
> > + msg.ptr_shape.width = 1;
> > + msg.ptr_shape.height = 1;
> > + msg.ptr_shape.hot_x = 0;
> > + msg.ptr_shape.hot_y = 0;
> > + msg.ptr_shape.data[0] = 0;
> > + msg.ptr_shape.data[1] = 1;
> > + msg.ptr_shape.data[2] = 1;
> > + msg.ptr_shape.data[3] = 1;
> > + hyperv_sendpacket(hdev, &msg);
> > +
>
> Is it necessary to send SYNTHVID_POINTER_SHAPE here? Perhaps we should

According to my test, yes. If I don't send a SYNTHVID_POINTER_SHAPE message,
the unwanted mouse pointer can't be hidden. As we know, the protocol between
the VSC and the VSP is not well documented to us. I can ask Hyper-V
team for some clarification on this, but it's probably we can just use the current
version of hiding the mouse pointer as-is -- this has been used for 10+ years
in the hyperv_fb driver without any issue. :-)

> separate SYNTHVID_POINTER_POSITION and SYNTHVID_POINTER_SHAPE into
> different functions.

Since the 2 messages are only used here, I suggest we keep it as-is.

Thanks,
-- Dexuan

2021-09-17 00:41:21

by Deepak Rawat

[permalink] [raw]
Subject: Re: [PATCH] drm/hyperv: Fix double mouse pointers

HI Dexuan, thanks for confirming. Could you please add this as a
comment to the function.

Reviewed-by: Deepak Rawat <[email protected]>

On Tue, Sep 14, 2021 at 11:59 PM Dexuan Cui <[email protected]> wrote:
>
> > From: Deepak Rawat <[email protected]>
> > Sent: Tuesday, September 14, 2021 8:59 AM
> > ...
> > > +/* Send mouse pointer info to host */
> > > +int hyperv_send_ptr(struct hv_device *hdev)
> > > +{
> > > + struct synthvid_msg msg;
> > > +
> > > + memset(&msg, 0, sizeof(struct synthvid_msg));
> > > + msg.vid_hdr.type = SYNTHVID_POINTER_POSITION;
> > > + msg.vid_hdr.size = sizeof(struct synthvid_msg_hdr) +
> > > + sizeof(struct synthvid_pointer_position);
> > > + msg.ptr_pos.is_visible = 1;
> >
> > "is_visible" should be 0 since you want to hide the pointer. Maybe
> > better, accept these from the caller.
>
> According to my test, "is_visible = 0" doesn't work, i.e. can't hide the
> unwanted HW mouse poiner. It looks like the field is for some very old
> legacy Windows VMs like Windows Vista.
>
> Haiyang also replied in another email, saying "is_visible = 0" doesn't
> work.
>
> > > + msg.ptr_pos.video_output = 0;
> > > + msg.ptr_pos.image_x = 0;
> > > + msg.ptr_pos.image_y = 0;
> > > + hyperv_sendpacket(hdev, &msg);
> > > +
> > > + memset(&msg, 0, sizeof(struct synthvid_msg));
> > > + msg.vid_hdr.type = SYNTHVID_POINTER_SHAPE;
> > > + msg.vid_hdr.size = sizeof(struct synthvid_msg_hdr) +
> > > + sizeof(struct synthvid_pointer_shape);
> > > + msg.ptr_shape.part_idx = SYNTHVID_CURSOR_COMPLETE;
> > > + msg.ptr_shape.is_argb = 1;
> > > + msg.ptr_shape.width = 1;
> > > + msg.ptr_shape.height = 1;
> > > + msg.ptr_shape.hot_x = 0;
> > > + msg.ptr_shape.hot_y = 0;
> > > + msg.ptr_shape.data[0] = 0;
> > > + msg.ptr_shape.data[1] = 1;
> > > + msg.ptr_shape.data[2] = 1;
> > > + msg.ptr_shape.data[3] = 1;
> > > + hyperv_sendpacket(hdev, &msg);
> > > +
> >
> > Is it necessary to send SYNTHVID_POINTER_SHAPE here? Perhaps we should
>
> According to my test, yes. If I don't send a SYNTHVID_POINTER_SHAPE message,
> the unwanted mouse pointer can't be hidden. As we know, the protocol between
> the VSC and the VSP is not well documented to us. I can ask Hyper-V
> team for some clarification on this, but it's probably we can just use the current
> version of hiding the mouse pointer as-is -- this has been used for 10+ years
> in the hyperv_fb driver without any issue. :-)
>
> > separate SYNTHVID_POINTER_POSITION and SYNTHVID_POINTER_SHAPE into
> > different functions.
>
> Since the 2 messages are only used here, I suggest we keep it as-is.
>
> Thanks,
> -- Dexuan

2021-09-17 02:35:40

by Dexuan Cui

[permalink] [raw]
Subject: RE: [PATCH] drm/hyperv: Fix double mouse pointers

> From: Deepak Rawat <[email protected]>
> Sent: Thursday, September 16, 2021 9:17 AM
> To: Dexuan Cui <[email protected]>
> Cc: Haiyang Zhang <[email protected]>; David Airlie <[email protected]>;
> Daniel Vetter <[email protected]>; Thomas Zimmermann
> <[email protected]>; [email protected];
> [email protected]; [email protected]
> Subject: Re: [PATCH] drm/hyperv: Fix double mouse pointers
>
> HI Dexuan, thanks for confirming. Could you please add this as a
> comment to the function.
>
> Reviewed-by: Deepak Rawat <[email protected]>

Thanks, Deepak!
Will do, and I'll rename the function to hyperv_hide_hw_ptr() to
better express the intent of the function.