[PATCH 0/3] Fix Thumb-2 undef handling for mixed-arch kernels
dave.martin at linaro.org
Tue Aug 16 12:06:52 EDT 2011
On Tue, Aug 16, 2011 at 3:58 PM, Tixy <tixy at yxit.co.uk> wrote:
> On Tue, 2011-08-16 at 15:14 +0100, Dave Martin wrote:
>> In kernels which support v6 and v7 platforms in a single binary
>> such as omap2plus_defconfig for example, undefined instruction
>> exceptions taken on Thumb instructions are not processed correctly,
>> because the kernel assumes at build-time that Thumb-2 won't be
>> supported in userspace.
>> This series implements a workaround, by allowing the __und_usr
>> handler to check the CPU architecture at runtime, in affected
>> Changes since RFC:
>> * Renamed the global variable to __cpu_architecture and provided
>> cpu_architecture() as in inline function in <asm/system.h>.
>> This brings back the old API, but more efficiently.
>> * Dropped all the patches required to handle the reverted API
>> * cpu_architecture is now declared __pure, which may lead to
>> slightly more efficient code in some cases.
>> * Added BUG_ON() to cpu_architecture() so that if
>> __cpu_architecture is not set early enough, it gets noticed.
>> Thanks to Tixy and Nicolas Pitre for their helpful feedback which
>> helped slim down this series.
>> Dave Martin (3):
>> ARM: Make cpu_alignment into a global variable
>> ARM: entry: Remove unnecessary masking when decoding Thumb-2
>> ARM: entry: Fix Thumb-2 undef handling for multi-CPU kernels
>> arch/arm/include/asm/system.h | 11 +++++++++-
>> arch/arm/kernel/entry-armv.S | 44 ++++++++++++++++++++++++++++++++++++----
>> arch/arm/kernel/setup.c | 5 +++-
>> 3 files changed, 53 insertions(+), 7 deletions(-)
> Looks good to me.
Thanks for looking over it.
Is that a Reviewed-by, or will you go for an Ack?
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