Commit b9338a78 authored Sep 09, 2007 by Tzachi Perelstein Committed by Russell King Sep 13, 2007

[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 <rmk+kernel@arm.linux.org.uk>

parent a53d6fb8

arch/arm/vfp/vfpmodule.c

+1 −0

Original line number	Diff line number	Diff line
		@@ -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;

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