Messages in this thread | | | Date | Fri, 19 Jun 2015 18:54:47 +0800 | From | Hanjun Guo <> | Subject | Re: [PATCH v2 0/3] Correct for ACPI 5.1->6.0 spec changes in MADT GICC entries |
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On 06/19/2015 06:36 AM, Al Stone wrote: > In the ACPI 5.1 version of the spec, the struct for the GICC subtable > (struct acpi_madt_generic_interrupt) of the MADT 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. > > Note that this was found in linux-next and these patches apply against > that tree and the arm64 kernel tree; 4.1-rc8 does not appear to have this > problem since it still has the 5.1 struct definition. > > Even though there is precendent in ia64 code for ignoring the changes in > size, this patch set instead tries to verify correctness. The first patch > in the set adds macros for easily using the ACPI spec version. The second > patch adds the BAD_MADT_GICC_ENTRY() macro that uses the version macros to > check the GICC subtable only, accounting for the difference in specification > versions that are possible. The final patch replaces BAD_MADT_ENTRY usage > with the BAD_MADT_GICC_ENTRY macro in arm64 code, which is currently the > only architecture affected. The BAD_MADT_ENTRY() will continue to work as > is for all other MADT subtables. > > I have tested these patches on an APM Mustang with version 1.15 firmware, > where the problem was found, and they fix the problem.
I also tested on QEMU, it fixed the problem when I was using ACPICA 6.0 updates for MADT table,
Tested-by: Hanjun Guo <hanjun.guo@linaro.org>
Thanks Hanjun
> > Changes for v2: > -- Replace magic constants with proper defines (Lorenzo) > -- Minor syntax clean-up noted by checkpatch > -- Send out CCs properly this time > -- Minor clean-up of the paragraphs in this cover letter > > > Al Stone (3): > ACPI : introduce macros for using the ACPI specification version > ACPI: add BAD_MADT_GICC_ENTRY() macro > ACPI / ARM64 : use the new BAD_MADT_GICC_ENTRY macro > > arch/arm64/kernel/smp.c | 2 +- > drivers/irqchip/irq-gic.c | 2 +- > include/linux/acpi.h | 15 +++++++++++++++ > 3 files changed, 17 insertions(+), 2 deletions(-) > -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in Please read the FAQ at http://www.tux.org/lkml/
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