linux-kernel - Re: [PATCH v4 6/6] x86/microcode/intel: Print when early microcode loading fails

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Message-ID: <f7ca6ffb-d623-a22e-da5e-d0acdd3ad672@intel.com>
Date:   Tue, 17 Jan 2023 08:35:33 -0800
From:   Dave Hansen <dave.hansen@...el.com>
To:     Ashok Raj <ashok.raj@...el.com>, Borislav Petkov <bp@...en8.de>,
        Thomas Gleixner <tglx@...utronix.de>
Cc:     X86-kernel <x86@...nel.org>,
        LKML Mailing List <linux-kernel@...r.kernel.org>,
        Tony Luck <tony.luck@...el.com>,
        Ingo Molnar <mingo@...nel.org>, alison.schofield@...el.com,
        reinette.chatre@...el.com, Tom Lendacky <thomas.lendacky@....com>
Subject: Re: [PATCH v4 6/6] x86/microcode/intel: Print when early microcode
 loading fails

On 1/9/23 07:35, Ashok Raj wrote:
> -static void print_ucode(int old_rev, int new_rev, int date)
> +static void print_ucode(bool failed, int old_rev, int new_rev, int date)
...
>  	if (rev != mc->hdr.rev)
> -		return -1;
> +		retval = -1;
>  
>  	uci->cpu_sig.rev = rev;
>  
>  	if (early)
> -		print_ucode(old_rev, uci->cpu_sig.rev, mc->hdr.date);
> +		print_ucode(retval, old_rev, mc->hdr.rev, mc->hdr.date);
>  	else
> -		print_ucode_info(old_rev, uci->cpu_sig.rev, mc->hdr.date);
> +		print_ucode_info(retval, old_rev, uci->cpu_sig.rev, mc->hdr.date);
>  
> -	return 0;
> +	return retval;
>  }

I'm generally not a _huge_ fan of having an 'int' implicitly cast to a
bool.  The:

	print_ucode_info(retval, ...

Line could be right or wrong based on what the retval is logically.
This, on the other hand:

	bool failed = false;
	...
	if (rev != mc->hdr.rev) {
		retval = -1;
		failed = true;
	}
	...
	print_ucode_info(failed, old_rev, uci->cpu_sig.rev, ...

*Clearly* and unambiguously matches up with:

	static void print_ucode(bool failed, int old_rev, ...