From: Tzachi Perelstein Date: Sun, 9 Sep 2007 13:24:59 +0000 (+0100) Subject: [ARM] 4567/1: Fix 'Oops - undefined instruction' when CONFIG_VFP=y on non VFP device X-Git-Tag: v2.6.23-rc7~45^2 X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=b9338a78fc21e980d33c58b31f3bb37cd48a68f6;p=linux-2.6 [ARM] 4567/1: Fix 'Oops - undefined instruction' when CONFIG_VFP=y on non VFP device vfp_init() takes care of the condition when CONFIG_VFP=y but no real VFP device exists. However, when this condition is true, a compiler might misplace code lines in a way that will break this support. (To be more specific - fmrx(FPSID) might be executed before vfp_testing_entry assignment, which will end up with Oops - undefined instruction). This patch adds a barrier() to guarantee the right execution ordering. Signed-off-by: Assaf Hoffman Signed-off-by: Russell King --- diff --git a/arch/arm/vfp/vfpmodule.c b/arch/arm/vfp/vfpmodule.c index 04ddab2bd8..eea3f50743 100644 --- a/arch/arm/vfp/vfpmodule.c +++ b/arch/arm/vfp/vfpmodule.c @@ -323,6 +323,7 @@ static int __init vfp_init(void) * we just need to read the VFPSID register. */ vfp_vector = vfp_testing_entry; + barrier(); vfpsid = fmrx(FPSID); barrier(); vfp_vector = vfp_null_entry;