ARM: 7592/1: nommu: prevent generation of kernel unaligned memory accesses
authorWill Deacon <will.deacon@arm.com>
Tue, 4 Dec 2012 11:56:44 +0000 (12:56 +0100)
committerRussell King <rmk+kernel@arm.linux.org.uk>
Fri, 7 Dec 2012 11:48:57 +0000 (11:48 +0000)
commite91b36efe51b5cbbfe5eb61a653cde5985ae8285
tree2b003a99db9afedbdeca8c795ca6e06716a5b3d5
parent76e0920403d3de1a9ed39cffc3ec9fcb00fa4bc9
ARM: 7592/1: nommu: prevent generation of kernel unaligned memory accesses

Recent ARMv7 toolchains assume that unaligned memory accesses will not
fault and will instead be handled by the processor.

For the nommu case (without an MPU), memory will be treated as
strongly-ordered and therefore unaligned accesses may fault regardless
of the SCTLR.A setting.

This patch passes -mno-unaligned-access to GCC when compiling for nommu
targets, preventing the generation of unaligned memory access in the
kernel.

Acked-by: Nicolas Pitre <nico@linaro.org>
Tested-by: Jonathan Austin <jonathan.austin@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
arch/arm/Makefile