From mboxrd@z Thu Jan 1 00:00:00 1970 From: dave.martin@linaro.org (Dave Martin) Date: Thu, 18 Aug 2011 18:01:51 +0100 Subject: [PATCH v2 0/3] Fix Thumb-2 undef handling for mixed-arch kernels Message-ID: <1313686914-29481-1-git-send-email-dave.martin@linaro.org> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org 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 kernels. Changes since v1: * Because cpu_architecture() is no longer trivial, it has been moveed back out of line, into setup.c. Changes since RFC: * Renamed the global variable to __cpu_architecture and provided cpu_architecture() as in inline function in . This brings back the old API, but more efficiently. * Dropped all the patches required to handle the reverted API change. * 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_architecture into a global variable ARM: entry: Remove unnecessary masking when decoding Thumb-2 instructions ARM: entry: Fix Thumb-2 undef handling for multi-CPU kernels arch/arm/include/asm/system.h | 3 +- arch/arm/kernel/entry-armv.S | 44 ++++++++++++++++++++++++++++++++++++---- arch/arm/kernel/setup.c | 20 +++++++++++++++++- 3 files changed, 60 insertions(+), 7 deletions(-) -- 1.7.4.1