On Fri, 1 May 2020 10:13:10 -0500 Josh Poimboeuf <jpoim...@redhat.com> wrote:
> On Fri, May 01, 2020 at 09:24:04AM -0400, Steven Rostedt wrote: > > On Fri, 1 May 2020 00:17:06 -0500 > > Josh Poimboeuf <jpoim...@redhat.com> wrote: > > > > > > Would it be easier to just call a new __text_poke_bp() which skips the > > > > SYSTEM_BOOTING check, since you know the trampoline will always be > > > > read-only? > > > > > > > > Like: > > > > > > early_trace_init() is called after mm_init(), so I thought it might > > > work, but I guess not: > > > > Yeah, I was about to say that this happens before mm_init() ;-) > > It happens *after* mm_init(). But now text_poke() has a dependency on > poking_init(), has a dependency on proc_caches_init(), which has a > dependency on kmem_cache_init_late(), etc. > > So how early do you need early_trace_init()? I'm assuming moving it to > after kmem_cache_init_late() would be too late. People have asked to move it even earlier. The point of having it early is to allow tracing to debug early boot up. > > > It's why we already have magic for enabling function tracing the first time. > > > > Do you see anything wrong with this current solution? It probably needs > > more comments, but I wanted to get acceptance on the logic before I go and > > pretty it up and send a non RFC patch. > > Assuming we can't get text_poke() working earlier, it seems reasonable > to me. > Thanks. Peter, what about you? -- Steve
