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From:   Dexuan Cui <decui@microsoft.com>
To:     Wei Hu <weh@microsoft.com>,
        "b.zolnierkie@samsung.com" <b.zolnierkie@samsung.com>,
        KY Srinivasan <kys@microsoft.com>,
        Haiyang Zhang <haiyangz@microsoft.com>,
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        "robin.murphy@arm.com" <robin.murphy@arm.com>,
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        Michael Kelley <mikelley@microsoft.com>
Subject: RE: [PATCH] video: hyperv: hyperv_fb: Use physical memory for fb on
 HyperV Gen 1 VMs.
Thread-Topic: [PATCH] video: hyperv: hyperv_fb: Use physical memory for fb on
 HyperV Gen 1 VMs.
Thread-Index: AQHViMlWrXYtpApox02C+wFzOSr7Mqd3cNRA
Date:   Sat, 2 Nov 2019 06:17:21 +0000
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References: <20191022110905.4032-1-weh@microsoft.com>
In-Reply-To: <20191022110905.4032-1-weh@microsoft.com>
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> From: linux-hyperv-owner@vger.kernel.org
> <linux-hyperv-owner@vger.kernel.org> On Behalf Of Wei Hu
> Sent: Tuesday, October 22, 2019 4:11 AM
> ...=20
> +	/* Allocate from CMA */
> +	// request_pages =3D (request_size >> PAGE_SHIFT) + 1;

"//" seems rare in Linux kernel code.
IMO "/* */" is more common.

> +			pr_info("Unable to allocate enough contiguous physical memory
> on Gen 1 VM. Use MMIO instead.\n");

The line exceeds 80 chars.
=20
> @@ -1060,6 +1168,7 @@ static int hvfb_probe(struct hv_device *hdev,
>  	par =3D info->par;
>  	par->info =3D info;
>  	par->fb_ready =3D false;
> +	par->need_docopy =3D false;

Maybe it's better if we set the default value to true? This way we can save
the "	par->need_docopy =3D true;" in hvfb_getmem().

Thanks,
-- Dexuan