On Mon, 20 Dec 2021, Christophe Leroy wrote: > Implement CONFIG_DYNAMIC_FTRACE_WITH_ARGS. It accelerates the call > of livepatching. > > Also note that powerpc being the last one to convert to > CONFIG_DYNAMIC_FTRACE_WITH_ARGS, it will now be possible to remove > klp_arch_set_pc() on all architectures. Correct. We could replace it ftrace_instruction_pointer_set() and that is it. In fact, livepatch.h in both arch/x86/include/asm/ and arch/s390/include/asm/ could be removed with that. On the other hand, there is arm64 live patching support being worked on and I am not sure what their plans about DYNAMIC_FTRACE_WITH_ARGS are. The above would make it a prerequisite. Adding CCs... you can find the whole thread at https://lore.kernel.org/all/cover.1640017960.git.christophe.leroy@xxxxxxxxxx/ Miroslav
