On powerpc64, -mprofile-kernel results in two instructions being emitted: 'mflr r0' and 'bl _mcount'. So far, we were only nop'ing out the branch to _mcount(). This series implements an approach to also nop out the preceding mflr.
Patches 1-3 are generic changes. Patch 2 is a fix for x86, but has not been tested. Patch 4 implements the changes for powerpc64. - Naveen Naveen N. Rao (4): ftrace: Expose flags used for ftrace_replace_code() x86/ftrace: Fix use of flags in ftrace_replace_code() ftrace: Expose __ftrace_replace_code() powerpc/ftrace: Additionally nop out the preceding mflr with -mprofile-kernel arch/powerpc/kernel/trace/ftrace.c | 188 +++++++++++++++++++++++++---- arch/x86/kernel/ftrace.c | 3 +- include/linux/ftrace.h | 6 + kernel/trace/ftrace.c | 13 +- 4 files changed, 178 insertions(+), 32 deletions(-) -- 2.21.0