Re: [PATCH v4 1/2] ACPI / ARM64: add BAD_MADT_GICC_ENTRY() macro

From	Will Deacon <will.deacon@arm.com>
Newsgroups	linux.kernel
Subject	Re: [PATCH v4 1/2] ACPI / ARM64: add BAD_MADT_GICC_ENTRY() macro
Date	2015-07-07 11:30 +0200
Message-ID	<pJxmp-3Rm-7@gated-at.bofh.it> (permalink)
References	<pJnQ6-6hC-3@gated-at.bofh.it> <pJnQ6-6hC-9@gated-at.bofh.it>
Organization	linux.* mail to news gateway

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On Tue, Jul 07, 2015 at 12:16:47AM +0100, Al Stone wrote:
> From: Al Stone <al.stone@.linaro.org>
> 
> The BAD_MADT_ENTRY() macro is designed to work for all of the subtables
> of the MADT.  In the ACPI 5.1 version of the spec, the struct for the
> GICC subtable (struct acpi_madt_generic_interrupt) is 76 bytes long; in
> ACPI 6.0, the struct is 80 bytes long.  But, there is only one definition
> in ACPICA for this struct -- and that is the 6.0 version.  Hence, when
> BAD_MADT_ENTRY() compares the struct size to the length in the GICC
> subtable, it fails if 5.1 structs are in use, and there are systems in
> the wild that have them.
> 
> This patch adds the BAD_MADT_GICC_ENTRY() that checks the GICC subtable
> only, accounting for the difference in specification versions that are
> possible.  The BAD_MADT_ENTRY() will continue to work as is for all other
> MADT subtables.
> 
> This code is being added to an arm64 header file since that is currently
> the only architecture using the GICC subtable of the MADT.  As a GIC is
> specific to ARM, it is also unlikely the subtable will be used elsewhere.
> 
> Fixes: aeb823bbacc2 (ACPICA: ACPI 6.0: Add changes for FADT table.)
> Signed-off-by: Al Stone <al.stone@linaro.org>
> ---
>  arch/arm64/include/asm/acpi.h | 8 ++++++++
>  1 file changed, 8 insertions(+)

Not the nicest patch I've ever seen, but if it gets things working again:

  Acked-by: Will Deacon <will.deacon@arm.com>

Catalin, I assume you're picking these two up for 4.2?

Will
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Re: [PATCH v4 1/2] ACPI / ARM64: add BAD_MADT_GICC_ENTRY() macro Will Deacon <will.deacon@arm.com> - 2015-07-07 11:30 +0200

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