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author | Dimitry Andric <dim@FreeBSD.org> | 2011-01-04 20:51:28 +0000 |
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committer | Dimitry Andric <dim@FreeBSD.org> | 2011-01-04 20:51:28 +0000 |
commit | e1724647283748daff0b5dae2338c301bf88e1ee (patch) | |
tree | c2e889dfe60be3e3786f90f9d27b561552cedc86 /libexec/rtld-elf/amd64 | |
parent | 7606ddab281e7159937ee8b1e4027540e6279bff (diff) | |
download | src-e1724647283748daff0b5dae2338c301bf88e1ee.tar.gz src-e1724647283748daff0b5dae2338c301bf88e1ee.zip |
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.
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
Notes
Notes:
svn path=/head/; revision=216977
Diffstat (limited to 'libexec/rtld-elf/amd64')
-rw-r--r-- | libexec/rtld-elf/amd64/Makefile.inc | 1 |
1 files changed, 1 insertions, 0 deletions
diff --git a/libexec/rtld-elf/amd64/Makefile.inc b/libexec/rtld-elf/amd64/Makefile.inc index 4ecf82fbab8e..7d6861183064 100644 --- a/libexec/rtld-elf/amd64/Makefile.inc +++ b/libexec/rtld-elf/amd64/Makefile.inc @@ -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 |