This is a note to let you know that I've just added the patch titled
drm/hyperv: Don't overwrite dirt_needed value set by host
to the 5.15-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
drm-hyperv-don-t-overwrite-dirt_needed-value-set-by-.patch
and it can be found in the queue-5.15 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit ce907e3637467bfd832a98cc1e8e1b60b150107b
Author: Saurabh Sengar <ssengar@xxxxxxxxxxxxxxxxxxx>
Date: Fri Sep 23 10:09:50 2022 +0000
drm/hyperv: Don't overwrite dirt_needed value set by host
[ Upstream commit 19b5e6659eaf537ebeac90ae30c7df0296fe5ab9 ]
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 <ssengar@xxxxxxxxxxxxxxxxxxx>
Reviewed-by: Dexuan Cui <decui@xxxxxxxxxxxxx>
Reviewed-by: Michael Kelley <mikelley@xxxxxxxxxxxxx>
Link: https://lore.kernel.org/r/1662996766-19304-1-git-send-email-ssengar@xxxxxxxxxxxxxxxxxxx
Signed-off-by: Wei Liu <wei.liu@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/drivers/gpu/drm/hyperv/hyperv_drm_drv.c b/drivers/gpu/drm/hyperv/hyperv_drm_drv.c
index 00e53de4812bb..584d3a73db96c 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;
