[PATCH v3 2/2] cmd: acpi: fix acpi list command

[Andy Shevchenko]

On Sat, Nov 18, 2023 at 11:52:48PM +0100, Heinrich Schuchardt wrote:
> ACPI tables may comprise either RSDT, XSDT, or both. The current code fails
> to check the presence of the RSDT table before accessing it. This leads to
> an exception if the RSDT table is not provided.
> 
> The XSDT table takes precedence over the RSDT table.
> 
> The return values of list_rsdt() and list_rsdp() are always zero and not
> checked. Remove the return values.
> 
> Addresses in the XSDT table are 64-bit. Adjust the output accordingly.
> 
> As the RSDT table has to be ignored if the XSDT command is present there is
> no need to compare the tables in a display command. Anyway the
> specification does not require that the sequence of addresses in the RSDT
> and XSDT table are the same.
> 
> The FACS table header does not provide revision information. Correct the
> description of dump_hdr().
> 
> Adjust the ACPI test to match the changed output format of the 'acpi list'
> command.

(Side question: Do you use --histogram when preparing patches? if no, try it.)

...


> +		if (rsdp->xsdt_address) {
> +			if (!xsdt->entry[i])
> +				break;
> +			hdr = map_sysmem(xsdt->entry[i], 0);
> +		} else {
> +			if (!rsdt->entry[i])
> +				break;
> +			hdr = map_sysmem(rsdt->entry[i], 0);
> +		}

With a help of temporary variable this can be rewritten as

		tmp = 0; // or NULL, I haven't checked the type.

		if (rsdp->xsdt_address)
			tmp = xsdt->entry[i];
		else
			tmp = rsdt->entry[i];

		if (!tmp)
			break;

		hdr = map_sysmem(tmp, 0);


-- 
With Best Regards,
Andy Shevchenko