Re: [PATCH v2 12/39] x86/ibt,ftrace: Search for __fentry__ location

[Naveen N. Rao]

Steven Rostedt wrote:
> On Fri, 25 Feb 2022 19:20:08 +0900
> Masami Hiramatsu <mhiramat@xxxxxxxxxx> wrote:
>
> > > No. It only acts like ftrace_location_range(sym, sym_end) if the passed
> > > in argument is the ip of the function (kallsyms returns offset = 0)  
> >
> > Got it. So now ftrace_location() will return the ftrace address
> > when the ip == func or ip == mcount-call.

Won't this cause issues with ftrace_set_filter_ip() and others? If the 
passed-in ip points to func+0 when the actual ftrace location is at some 
offset, the ftrace location check in ftrace_match_addr() will now pass, 
resulting in adding func+0 to the hash. Should we also update 
ftrace_match_addr() to use the ip returned by ftrace_location()?


- Naveen