Re: [RFC 0/4] arm64: add livepatch support

On Fri, 24 Apr 2015, AKASHI Takahiro wrote:

This patchset enables livepatch support on arm64.

Livepatch was merged in v4.0, and allows replacying a function dynamically based on ftrace framework, but it also requires -mfentry option of gcc. Currently arm64 gcc doesn't support it, but by adding a helper function to ftrace, we will be able to support livepatch on arch's which don't support this option.

I submit this patchset as RFC since I'm not quite sure that I'm doing in the right way, or we should definitely support -fentry instead.

I don't have arm64 cross-compiler handy, could you please copy/paste how does function prologue, generated by gcc -pg on arm64 look like?

Thanks,