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Date: Wed, 5 Jun 2024 22:14:15 +0200
From: Borislav Petkov <bp@alien8.de>
To: Ashish Kalra <Ashish.Kalra@amd.com>
Cc: tglx@linutronix.de, mingo@redhat.com, dave.hansen@linux.intel.com,
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Subject: Re: [PATCH v7 2/3] x86/boot/compressed: Skip Video Memory access in
 Decompressor for SEV-ES/SNP.
Message-ID: <20240605201415.GZZmDHF9-lThZ6XQOz@fat_crate.local>
References: <20240528095522.509667-1-kirill.shutemov@linux.intel.com>
 <cover.1717111180.git.ashish.kalra@amd.com>
 <75a313a44bfaf3f97027393665d625be2f881e66.1717111180.git.ashish.kalra@amd.com>
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In-Reply-To: <75a313a44bfaf3f97027393665d625be2f881e66.1717111180.git.ashish.kalra@amd.com>

On Thu, May 30, 2024 at 11:37:14PM +0000, Ashish Kalra wrote:
> -	lines = boot_params_ptr->screen_info.orig_video_lines;
> -	cols = boot_params_ptr->screen_info.orig_video_cols;
> +	if (!(sev_status & MSR_AMD64_SEV_ES_ENABLED)) {
> +		lines = boot_params_ptr->screen_info.orig_video_lines;
> +		cols = boot_params_ptr->screen_info.orig_video_cols;
> +	}

By now I get an allergic reaction from this sprinkling of "if sev..."
everywhere in the code.

>  	init_default_io_ops();

<--- right here there's a call to

	early_tdx_detect();

You can add a early_sev_detect() counterpart here and clear lines and
cols in it along with an explanation why it is being done.

This is at least a bit cleaner than this.

Thx.

-- 
Regards/Gruss,
    Boris.

https://people.kernel.org/tglx/notes-about-netiquette