Re: [PATCH v3 02/19] x86/boot: Move mem_encrypt= parsing to the decompressor

[Borislav Petkov]

On Mon, Jan 29, 2024 at 07:05:05PM +0100, Ard Biesheuvel wrote:
> +/*
> + * Set the memory encryption xloadflag based on the mem_encrypt= command line
> + * parameter, if provided. If not, the consumer of the flag decides what the
> + * default behavior should be.
> + */
> +static void set_mem_encrypt_flag(struct setup_header *hdr)

parse_mem_encrypt

> +{
> +	hdr->xloadflags &= ~(XLF_MEM_ENCRYPTION | XLF_MEM_ENCRYPTION_ENABLED);
> +
> +	if (IS_ENABLED(CONFIG_ARCH_HAS_MEM_ENCRYPT)) {

That's unconditionally enabled on x86:

	select ARCH_HAS_MEM_ENCRYPT

in x86/Kconfig.

Which sounds like you need a single XLF_MEM_ENCRYPT and simplify this
more.

> +		int on = cmdline_find_option_bool("mem_encrypt=on");
> +		int off = cmdline_find_option_bool("mem_encrypt=off");
> +
> +		if (on || off)
> +			hdr->xloadflags |= XLF_MEM_ENCRYPTION;
> +		if (on > off)
> +			hdr->xloadflags |= XLF_MEM_ENCRYPTION_ENABLED;
> +	}
> +}

Otherwise, I like the simplification.

Thx.

-- 
Regards/Gruss,
    Boris.

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