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    Subject[PATCH] Move -fno-dwarf2-cfi-asm to powerpc only
    Move -fno-dwarf2-cfi-asm to powerpc only

    Better dwarf2 unwind information is a good thing, it allows better
    debugging with kgdb and crash and helps systemtap.

    commit 003086497f07f7f1e67c0c295e261740f822b377 disabled some CFI
    information globally to work around a module loader bug on powerpc.

    But this disables the better unwind tables for all architectures,
    not just powerpc. Move the workaround to powerpc and also
    add a suitable comment that's it really a workaround.

    This improves dwarf2 unwind tables on x86 at least.

    Cc: kyle@redhat.com
    Cc: benh@kernel.crashing.org
    Cc: mmarek@suse.cz

    Signed-off-by: Andi Kleen <ak@linux.intel.com>

    ---
    Makefile | 3 ---
    arch/powerpc/Makefile | 5 +++++
    2 files changed, 5 insertions(+), 3 deletions(-)

    Index: linux-2.6.33-rc1-ak/Makefile
    ===================================================================
    --- linux-2.6.33-rc1-ak.orig/Makefile
    +++ linux-2.6.33-rc1-ak/Makefile
    @@ -570,9 +570,6 @@ KBUILD_CFLAGS += $(call cc-option,-Wno-p
    # disable invalid "can't wrap" optimizations for signed / pointers
    KBUILD_CFLAGS += $(call cc-option,-fno-strict-overflow)

    -# revert to pre-gcc-4.4 behaviour of .eh_frame
    -KBUILD_CFLAGS += $(call cc-option,-fno-dwarf2-cfi-asm)
    -
    # conserve stack if available
    KBUILD_CFLAGS += $(call cc-option,-fconserve-stack)

    Index: linux-2.6.33-rc1-ak/arch/powerpc/Makefile
    ===================================================================
    --- linux-2.6.33-rc1-ak.orig/arch/powerpc/Makefile
    +++ linux-2.6.33-rc1-ak/arch/powerpc/Makefile
    @@ -112,6 +112,11 @@ KBUILD_CFLAGS += $(call cc-option,-mspe=
    # kernel considerably.
    KBUILD_CFLAGS += $(call cc-option,-funit-at-a-time)

    +# FIXME: the module load should be taught about the additional relocs
    +# generated by this.
    +# revert to pre-gcc-4.4 behaviour of .eh_frame
    +KBUILD_CFLAGS += $(call cc-option,-fno-dwarf2-cfi-asm)
    +
    # Never use string load/store instructions as they are
    # often slow when they are implemented at all
    KBUILD_CFLAGS += -mno-string

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