On Wed, 31 Oct 2018, Mark Rutland wrote: > I guess skipping the original function prologue would simplify the > implementation of the replacement function (and would mean that the regs > held the function arguments per the procedure call standard), but AFAICT > other architectures aren't relying on that, so it doesn't seem to be a > strict requirement. > > What am I missing? > > How does livepatching handle the pre-mcount function preambles on > architectures with existing support? Other architectures do rely on that. That's exactly for example why on x86 we use '-pg -mfentry', to make sure we hook the function *before* prologue. Thanks, -- Jiri Kosina SUSE Labs