Re: [PATCH v3 0/3] ftrace: Introduce PERMANENT ftrace_ops flag

[Miroslav Benes]

On Wed, 16 Oct 2019, Steven Rostedt wrote:

> On Wed, 16 Oct 2019 13:33:12 +0200
> Miroslav Benes <mbenes@xxxxxxx> wrote:
> 
> > Livepatch uses ftrace for redirection to new patched functions. It means
> > that if ftrace is disabled, all live patched functions are disabled as
> > well. Toggling global 'ftrace_enabled' sysctl thus affect it directly.
> > It is not a problem per se, because only administrator can set sysctl
> > values, but it still may be surprising.
> > 
> > Introduce PERMANENT ftrace_ops flag to amend this. If the
> > FTRACE_OPS_FL_PERMANENT is set on any ftrace ops, the tracing cannot be
> > disabled by disabling ftrace_enabled. Equally, a callback with the flag
> > set cannot be registered if ftrace_enabled is disabled.
> > 
> > v2->v3:
> > - ftrace_enabled explicitly set to true
> > - selftest from Joe Lawrence (I just split it to two patches)
> > - typo fix
> > 
> > v1->v2:
> > - different logic, proposed by Joe Lawrence
> > 
> > Joe Lawrence (2):
> >   selftests/livepatch: Make dynamic debug setup and restore generic
> >   selftests/livepatch: Test interaction with ftrace_enabled
> > 
> > Miroslav Benes (1):
> >   ftrace: Introduce PERMANENT ftrace_ops flag
> > 
> 
> Would you like me to take all three patches through my tree?

I think that would be the easiest, yes.

Thanks
Miroslav