svn commit: r216977 - in head/libexec/rtld-elf: amd64 i386

[Alexander Best]

On Tue Jan  4 11, Dimitry Andric wrote:
> Author: dim
> Date: Tue Jan  4 20:51:28 2011
> New Revision: 216977
> URL: http://svn.freebsd.org/changeset/base/216977
> 
> Log:
>   On amd64 and i386, tell the compiler to refrain from generating SSE,
>   3DNow, MMX and floating point instructions in rtld-elf.
>   
>   Otherwise, _rtld_bind() (and whatever it calls) could possibly clobber
>   function arguments that are passed in SSE/3DNow/MMX/FP registers,
>   usually floating point values.  This can happen, for example, when clang
>   generates SSE code for memset() or memcpy() calls.

the sorting order for these flags seems to be:

-mno-mmx -mno-3dnow -mno-sse -mno-sse2 -mno-sse3

see 'grep -R "\-no-sse" /usr/src'. maybe the sorting order should stay
consistent?

also what's the status of clang? will these flags make sure that newer
cpu extension won't be activated? i checked
contrib/llvm/tools/clang/include/clang/Driver/Options.td
and clang has support for:

-m3dnowa
-mssse3
-msse4a
-msse4
-msse4_1
-msse4_2
-maes
-mavx

since these extensions only get set in a hand full of files maybe special
cases for CC == clang can be added.

also maybe you could have a look at the attached patch. i sent this to hackers@
and nobody objected, but nobody wanted to commit the patch unfortunately.

cheers.
alex

>   
>   One symptom of this is sshd dying early on amd64 with "PRNG not seeded",
>   which is ultimately caused by libcrypto.so.6 calling RAND_add() with a
>   double parameter.  That parameter is passed via %xmm0, which gets wiped
>   out by an SSE memset() in _rtld_bind().
>   
>   Reviewed by:	kib, kan
> 
> Modified:
>   head/libexec/rtld-elf/amd64/Makefile.inc
>   head/libexec/rtld-elf/i386/Makefile.inc
> 
> Modified: head/libexec/rtld-elf/amd64/Makefile.inc
> ==============================================================================
> --- head/libexec/rtld-elf/amd64/Makefile.inc	Tue Jan  4 20:38:52 2011	(r216976)
> +++ head/libexec/rtld-elf/amd64/Makefile.inc	Tue Jan  4 20:51:28 2011	(r216977)
> @@ -1,5 +1,6 @@
>  # $FreeBSD$
>  
> +CFLAGS+=	-mno-sse -mno-sse2 -mno-sse3 -mno-mmx -mno-3dnow -msoft-float
>  # Uncomment this to build the dynamic linker as an executable instead
>  # of a shared library:
>  #LDSCRIPT=	${.CURDIR}/${MACHINE_CPUARCH}/elf_rtld.x
> 
> Modified: head/libexec/rtld-elf/i386/Makefile.inc
> ==============================================================================
> --- head/libexec/rtld-elf/i386/Makefile.inc	Tue Jan  4 20:38:52 2011	(r216976)
> +++ head/libexec/rtld-elf/i386/Makefile.inc	Tue Jan  4 20:51:28 2011	(r216977)
> @@ -1,5 +1,6 @@
>  # $FreeBSD$
>  
> +CFLAGS+=	-mno-sse -mno-sse2 -mno-sse3 -mno-mmx -mno-3dnow -msoft-float
>  # Uncomment this to build the dynamic linker as an executable instead
>  # of a shared library:
>  #LDSCRIPT=	${.CURDIR}/${MACHINE_CPUARCH}/elf_rtld.x

-- 
a13x
-------------- next part --------------
diff --git a/sys/boot/i386/boot2/Makefile b/sys/boot/i386/boot2/Makefile
index b91a43b..39ef619 100644
--- a/sys/boot/i386/boot2/Makefile
+++ b/sys/boot/i386/boot2/Makefile
@@ -3,7 +3,7 @@
 .include <bsd.own.mk>
 
 # XXX: clang can compile the boot code just fine, but boot2 gets too big
-CC:=${CC:C/^(.*\/)?clang$/gcc/1}
+#CC:=${CC:C/^(.*\/)?clang$/gcc/1}
 
 FILES=		boot boot1 boot2
 
@@ -31,7 +31,6 @@ CFLAGS=	-Os \
 	-fno-unit-at-a-time \
 	-mno-align-long-strings \
 	-mrtd \
-	-mno-mmx -mno-3dnow -mno-sse -mno-sse2 -mno-sse3 \
 	-D${BOOT2_UFS} \
 	-DFLAGS=${BOOT_BOOT1_FLAGS} \
 	-DSIOPRT=${BOOT_COMCONSOLE_PORT} \
diff --git a/sys/boot/i386/gptboot/Makefile b/sys/boot/i386/gptboot/Makefile
index a0fad61..452b100 100644
--- a/sys/boot/i386/gptboot/Makefile
+++ b/sys/boot/i386/gptboot/Makefile
@@ -26,7 +26,6 @@ CFLAGS=	-DBOOTPROG=\"gptboot\" \
 	-fno-unit-at-a-time \
 	-mno-align-long-strings \
 	-mrtd \
-	-mno-mmx -mno-3dnow -mno-sse -mno-sse2 -mno-sse3 \
 	-DGPT \
 	-D${GPTBOOT_UFS} \
 	-DSIOPRT=${BOOT_COMCONSOLE_PORT} \
diff --git a/sys/boot/i386/gptzfsboot/Makefile b/sys/boot/i386/gptzfsboot/Makefile
index 30a5fc7..7f5f287 100644
--- a/sys/boot/i386/gptzfsboot/Makefile
+++ b/sys/boot/i386/gptzfsboot/Makefile
@@ -23,7 +23,6 @@ CFLAGS=	-DBOOTPROG=\"gptzfsboot\" \
 	-fno-unit-at-a-time \
 	-mno-align-long-strings \
 	-mrtd \
-	-mno-mmx -mno-3dnow -mno-sse -mno-sse2 -mno-sse3 \
 	-DGPT -DBOOT2 \
 	-DSIOPRT=${BOOT_COMCONSOLE_PORT} \
 	-DSIOFMT=${B2SIOFMT} \
diff --git a/sys/boot/i386/zfsboot/Makefile b/sys/boot/i386/zfsboot/Makefile
index 10616e4..38e8a9f 100644
--- a/sys/boot/i386/zfsboot/Makefile
+++ b/sys/boot/i386/zfsboot/Makefile
@@ -24,7 +24,6 @@ CFLAGS=	-DBOOTPROG=\"zfsboot\" \
 	-fno-unit-at-a-time \
 	-mno-align-long-strings \
 	-mrtd \
-	-mno-mmx -mno-3dnow -mno-sse -mno-sse2 -mno-sse3 \
 	-DBOOT2 \
 	-DFLAGS=${BOOT_BOOT1_FLAGS} \
 	-DSIOPRT=${BOOT_COMCONSOLE_PORT} \
diff --git a/sys/boot/pc98/boot2/Makefile b/sys/boot/pc98/boot2/Makefile
index dfd8607..035b5dd 100644
--- a/sys/boot/pc98/boot2/Makefile
+++ b/sys/boot/pc98/boot2/Makefile
@@ -28,7 +28,6 @@ CFLAGS=	-Os \
 	-fno-unit-at-a-time \
 	-mno-align-long-strings \
 	-mrtd \
-	-mno-mmx -mno-3dnow -mno-sse -mno-sse2 -mno-sse3 \
 	-D${BOOT2_UFS} \
 	-DFLAGS=${BOOT_BOOT1_FLAGS} \
 	-DSIOPRT=${BOOT_COMCONSOLE_PORT} \