Re: [GIT PULL] x86/urgent for v5.11-rc7

On Mon, 8 Feb 2021 16:47:05 +0100
Peter Zijlstra [off-list ref] wrote:

quoted

/*
 * Convert a function address into the appropriate ftrace location.
 *
 * Usually this is just the address of the function, but on some architectures
 * it's more complicated so allow them to provide a custom behaviour.
 */
#ifndef klp_get_ftrace_location
static unsigned long klp_get_ftrace_location(unsigned long faddr)
{
	return faddr;
}
#endif  

I suppose the trivial fix is to see if it points to endbr64 and if so,
increment the addr by the length of that.

I thought of that too. But one thing that may be possible, is to use
kallsym. I believe you can get the range of a function (start and end of
the function) from kallsyms. Then ask ftrace for the addr in that range
(there should only be one).

-- Steve