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From:   Dexuan Cui <decui@microsoft.com>
To:     Saurabh Sengar <ssengar@linux.microsoft.com>,
        Saurabh Singh Sengar <ssengar@microsoft.com>,
        "drawat.floss@gmail.com" <drawat.floss@gmail.com>,
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        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        "Michael Kelley (LINUX)" <mikelley@microsoft.com>
Subject: RE: [PATCH] drm/hyperv: Don't overwrite dirt_needed value set by host
Thread-Topic: [PATCH] drm/hyperv: Don't overwrite dirt_needed value set by
 host
Thread-Index: AQHYxrzvcw8ZA8kTyUqhzpRLgwf6Z63cWQIQ
Date:   Mon, 12 Sep 2022 22:02:03 +0000
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> From: Saurabh Sengar <ssengar@linux.microsoft.com>
> 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.
>=20
> Signed-off-by: Saurabh Sengar <ssengar@linux.microsoft.com>

Reviewed-by: Dexuan Cui <decui@microsoft.com>