Re: [PATCH] drm/hyperv: Don't overwrite dirt_needed value set by host

2022-09-23 Thread Wei Liu
On Mon, Sep 12, 2022 at 08:32:46AM -0700, Saurabh Sengar wrote:
> Existing code is causing a race condition where dirt_needed value is
> already set by the host and gets overwritten with default value. Remove
> this default setting of dirt_needed, to avoid overwriting the value
> received in the channel callback set by vmbus_open. Removing this
> setting also means the default value for dirt_needed is changed to false
> as it's allocated by kzalloc which is similar to legacy hyperv_fb driver.
> 
> Signed-off-by: Saurabh Sengar 

Applied to hyperv-next. Thanks.

I ended up reconstructing the patch myself since the said driver
changed. It is only a one line change so that's fine. If the committed
patch is wrong, please let me know.


RE: [PATCH] drm/hyperv: Don't overwrite dirt_needed value set by host

2022-09-22 Thread Michael Kelley (LINUX)
From: Saurabh Sengar  Sent: Monday, September 12, 
2022 8:33 AM
> 
> Existing code is causing a race condition where dirt_needed value is
> already set by the host and gets overwritten with default value. Remove
> this default setting of dirt_needed, to avoid overwriting the value
> received in the channel callback set by vmbus_open. Removing this
> setting also means the default value for dirt_needed is changed to false
> as it's allocated by kzalloc which is similar to legacy hyperv_fb driver.
> 
> Signed-off-by: Saurabh Sengar 
> ---
>  drivers/gpu/drm/hyperv/hyperv_drm_drv.c | 2 --
>  1 file changed, 2 deletions(-)
> 
> diff --git a/drivers/gpu/drm/hyperv/hyperv_drm_drv.c
> b/drivers/gpu/drm/hyperv/hyperv_drm_drv.c
> index 4a8941fa0815..57d49a08b37f 100644
> --- a/drivers/gpu/drm/hyperv/hyperv_drm_drv.c
> +++ b/drivers/gpu/drm/hyperv/hyperv_drm_drv.c
> @@ -198,8 +198,6 @@ static int hyperv_vmbus_probe(struct hv_device *hdev,
>   if (ret)
>   drm_warn(dev, "Failed to update vram location.\n");
> 
> - hv->dirt_needed = true;
> -
>   ret = hyperv_mode_config_init(hv);
>   if (ret)
>   goto err_vmbus_close;
> --
> 2.31.1

Reviewed-by: Michael Kelley 



RE: [PATCH] drm/hyperv: Don't overwrite dirt_needed value set by host

2022-09-12 Thread Dexuan Cui
> From: Saurabh Sengar 
> Sent: Monday, September 12, 2022 8:33 AM
>  ...
> Existing code is causing a race condition where dirt_needed value is
> already set by the host and gets overwritten with default value. Remove
> this default setting of dirt_needed, to avoid overwriting the value
> received in the channel callback set by vmbus_open. Removing this
> setting also means the default value for dirt_needed is changed to false
> as it's allocated by kzalloc which is similar to legacy hyperv_fb driver.
> 
> Signed-off-by: Saurabh Sengar 

Reviewed-by: Dexuan Cui