diff options
Diffstat (limited to 'gnu-efi-disable-mmx-and-sse.patch')
| -rw-r--r-- | gnu-efi-disable-mmx-and-sse.patch | 53 |
1 files changed, 53 insertions, 0 deletions
diff --git a/gnu-efi-disable-mmx-and-sse.patch b/gnu-efi-disable-mmx-and-sse.patch new file mode 100644 index 000000000000..563661bec796 --- /dev/null +++ b/gnu-efi-disable-mmx-and-sse.patch @@ -0,0 +1,53 @@ +From d703c370c78578b63e7b5e04a3801c7f5fbf0c94 Mon Sep 17 00:00:00 2001 +From: Peter Jones <pjones@redhat.com> +Date: Fri, 31 May 2013 15:00:11 -0400 +Subject: [PATCH] Disable MMX and SSE. + +GCC 4.8.0 adds some optimizations that will use movups/movaps (and use +%xmm* registers) when they're faster, and of course that won't work at +all since UEFI firmwares aren't guaranteed to initialize the mmx/sse +instructions. + +This will be even more annoying, since most UEFI firmwares don't +initialize the #DE or #UD trap handlers, and your backtrace will be a +random path through uninitialized memory, occasionally including +whatever address the IDT has for #UD, but also addresses like "0x4" and +"0x507" that you don't normally expect to see in your call path. +--- + Make.defaults | 7 +++++-- + 1 file changed, 5 insertions(+), 2 deletions(-) + +diff --git a/Make.defaults b/Make.defaults +index 0585915..ea7513e 100644 +--- a/Make.defaults ++++ b/Make.defaults +@@ -60,7 +60,9 @@ CPPFLAGS = -DCONFIG_$(ARCH) + ifeq ($(GCCNEWENOUGH),1) + CPPFLAGS += -DGNU_EFI_USE_MS_ABI -maccumulate-outgoing-args --std=c11 + endif +-CFLAGS = $(ARCH3264) -O2 -fpic -Wall -fshort-wchar -fno-strict-aliasing -fno-merge-constants -ffreestanding -fno-stack-protector -fno-stack-check ++CFLAGS = $(ARCH3264) -O2 -fpic -Wall -fshort-wchar -fno-strict-aliasing \ ++ -fno-merge-constants -ffreestanding -fno-stack-protector \ ++ -fno-stack-check + ASFLAGS = $(ARCH3264) + LDFLAGS = -nostdlib --no-undefined + INSTALL = install +@@ -78,13 +80,14 @@ ifeq ($(ARCH),ia64) + endif + + ifeq ($(ARCH), ia32) ++ CFLAGS += -mno-mmx -mno-sse + ifeq ($(HOSTARCH), x86_64) + ARCH3264 = -m32 + endif + endif + + ifeq ($(ARCH), x86_64) +- CFLAGS += -mno-red-zone ++ CFLAGS += -mno-red-zone -mno-mmx -mno-sse + ifeq ($(HOSTARCH), ia32) + ARCH3264 = -m64 + endif +-- +1.8.2.1 + |