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Date:   Fri, 4 Aug 2023 17:39:21 +0100
From:   Will Deacon <will@kernel.org>
To:     Anshuman Khandual <anshuman.khandual@arm.com>
Cc:     linux-arm-kernel@lists.infradead.org, suzuki.poulose@arm.com,
        Sami Mujawar <sami.mujawar@arm.com>,
        Catalin Marinas <catalin.marinas@arm.com>,
        Mark Rutland <mark.rutland@arm.com>,
        Mike Leach <mike.leach@linaro.org>,
        Alexander Shishkin <alexander.shishkin@linux.intel.com>,
        coresight@lists.linaro.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH V3 1/4] arm_pmu: acpi: Refactor
 arm_spe_acpi_register_device()
Message-ID: <20230804163921.GE30679@willie-the-truck>
References: <20230803055652.1322801-1-anshuman.khandual@arm.com>
 <20230803055652.1322801-2-anshuman.khandual@arm.com>
 <89058c7c-1fed-60ea-7233-04187772a931@arm.com>
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On Thu, Aug 03, 2023 at 11:43:27AM +0530, Anshuman Khandual wrote:
> 
> 
> On 8/3/23 11:26, Anshuman Khandual wrote:
> > +	/*
> > +	 * Sanity check all the GICC tables for the same interrupt
> > +	 * number. For now, only support homogeneous ACPI machines.
> > +	 */
> > +	for_each_possible_cpu(cpu) {
> > +		struct acpi_madt_generic_interrupt *gicc;
> > +
> > +		gicc = acpi_cpu_get_madt_gicc(cpu);
> > +		if (gicc->header.length < len)
> > +			return gsi ? -ENXIO : 0;
> > +
> > +		this_gsi = parse_gsi(gicc);
> > +		if (!this_gsi)
> > +			return gsi ? -ENXIO : 0;
> 
> Hello Will,
> 
> Moved parse_gsi() return code checking to its original place just to
> make it similar in semantics to existing 'gicc->header.length check'.
> If 'gsi' is valid i.e atleast a single cpu has been probed, return
> -ENXIO indicating mismatch, otherwise just return 0.

Wouldn't that still be the case without the check in this hunk? We'd run
into the homogeneous check and return -ENXIO from there, no?

Will