Re: [PATCH] livepatch: add (un)patch hooks
From: Josh Poimboeuf
Date: Fri Jul 28 2017 - 14:29:08 EST
On Fri, Jul 28, 2017 at 02:08:33PM -0400, Joe Lawrence wrote:
> On 07/27/2017 05:36 PM, Josh Poimboeuf wrote:
> > On Thu, Jul 27, 2017 at 04:43:58PM -0400, Joe Lawrence wrote:
> >> On 07/20/2017 12:17 AM, Josh Poimboeuf wrote:
> >>> - The post-patch and post-unpatch hooks will need to be run from either
> >>> klp_complete_transition() or klp_module_coming/going(), depending on
> >>> whether the to-be-patched module is already loaded or is being
> >>> loaded/unloaded.
> >>
> >> You're suggesting that post-(un)patch-hooks:
> >>
> >> 1 - Notify klp_objects when a KLP_(UN)PATCHED transition completes
> >
> > Right. (From klp_complete_transition())
>
> We should be careful to only call hooks for those klp_objects that were
> actually (un)patched. I don't think there is such state that makes it
> all the way out to klp_complete_transition(), but since both the
> completion and module_coming/going code both operate under the
> klp_mutex, perhaps klp_is_object_loaded() is a sufficient check?
Yeah, the mutex makes it safe to just check klp_is_object_loaded().
--
Josh