Nicholas Piggin wrote:
Naveen N. Rao's on May 17, 2019 4:22 am:
While enabling ftrace, we will first need to patch the preceding 'mflr
r0' (which would now be a 'nop') with 'b +8', then use
synchronize_rcu_tasks() and finally patch in 'bl _mcount()' followed by
'mflr r0'.
I think that's what you meant, just that my reference to patching 'mflr
r0' with a 'b +8' should have called out that the mflr would have been
nop'ed out.
I meant that we don't need the b +8 anywhere, because the mflr r0
is harmless. Enabling ftrace just needs to patch in 'mflr r0', and
then synchronize_rcu_tasks(), and then patch in 'bl _mcount'. I think?
Ah, that's a good point! That should be enough and it simplifies this
further.
Thanks,
Naveen
