[Xen-devel] [PATCH] xen: arm: make sure gcc doesn't use floating-point registers on arm64

[Ian Campbell <ian.campbell@xxxxxxxxxx>]

By using -mgeneral-regs-only which is the Aarch64 equivalent to
-msoft-float.

Otherwise gcc will corrupt the d* registers, which we don't save/restore when
trapping to/from the hypervisor.

Signed-off-by: Ian Campbell <ian.campbell@xxxxxxxxxx>
---
Needless to say I consider this important for 4.4 backport...
---
 xen/arch/arm/Rules.mk |    1 +
 1 file changed, 1 insertion(+)

diff --git a/xen/arch/arm/Rules.mk b/xen/arch/arm/Rules.mk
index 76b35d9..b5bf5cb 100644
--- a/xen/arch/arm/Rules.mk
+++ b/xen/arch/arm/Rules.mk
@@ -28,6 +28,7 @@ endif
 
 ifeq ($(TARGET_SUBARCH),arm64)
 CFLAGS += -mcpu=generic
+CFLAGS += -mgeneral-regs-only # No fp registers etc
 arm32 := n
 arm64 := y
 endif
-- 
1.7.10.4


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