Messages in this thread | | | Date | Mon, 31 Oct 2022 17:02:47 +0100 | From | Petr Mladek <> | Subject | Re: [PATCH v2 3/4] livepatch/shadow: Introduce klp_shadow_type structure |
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On Wed 2022-10-26 16:41:21, Marcos Paulo de Souza wrote: > The shadow variable type will be used in klp_shadow_alloc/get/free > functions instead of id/ctor/dtor parameters. As a result, all callers > use the same callbacks consistently[*][**]. > > The structure will be used in the next patch that will manage the > lifetime of shadow variables and execute garbage collection automatically. > > [*] From the user POV, it might have been easier to pass $id instead > of pointer to struct klp_shadow_type. > > It would require registering the klp_shadow_type so that > the klp_shadow API could find ctor/dtor for the given id. > It actually will be needed for the garbage collection anyway > because it will define the lifetime of the variables. > > The bigger problem is that the same klp_shadow_type might be > used by more livepatch modules. Each livepatch module need > to duplicate the definition of klp_shadow_type and ctor/dtor > callbacks. The klp_shadow API would need to choose one registered > copy. > > The definitions should be compatible and they should stay as long > as the type is registered. But it still feels more safe when > klp_shadow API callers use struct klp_shadow_type and ctor/dtor > callbacks defined in the same livepatch module. > > This problem is gone when each livepatch explicitly uses its > own struct klp_shadow_type pointing to its own callbacks.
This paragraph seems redundant. It more or less repeats what is said in the previous one.
> [**] test_klp_shadow_vars.c uses a custom @dtor to show that it was called. > The message must be disabled when called via klp_shadow_free_all() > because the ordering of freed variables is not well defined there. > It has to be done using another hack after switching to > klp_shadow_types. > > Co-developed-by: Petr Mladek <pmladek@suse.com> > Signed-off-by: Petr Mladek <pmladek@suse.com> > Signed-off-by: Marcos Paulo de Souza <mpdesouza@suse.com>
I am never sure how the co-authoring should be done ;-) But I believe that the author should always be the first one. And the other author should be listed either by Co-developer-by: or by Signed-off-by: but not by both tags. So, it should be:
Signed-off-by: Marcos Paulo de Souza <mpdesouza@suse.com> Co-developed-by: Petr Mladek <pmladek@suse.com>
With the removed paragraph and updated tags:
Reviewed-by: Petr Mladek <pmladek@suse.com>
Best Regards, Petr
PS: No need to resend the patch. I could do the two changes when pushing it.
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