Re: [Devel] Re: [PATCH 1/3] Signal semantics for /sbin/init

[Daniel Pittman <daniel-zvVxMF7wGoXk1uMJSBkQmQ@public.gmane.org>]

Oleg Nesterov <oleg-6lXkIZvqkOAvJsYlp49lxw@public.gmane.org> writes:
> On 09/13, Cedric Le Goater wrote:
>> Oleg Nesterov wrote:

[...]

>> To respect the current init semantic,
>
> The current init semantic is broken in many ways ;)

Yup.  They sure are, but they are pretty set in stone by now. :)

>> shouldn't we discard any unblockable signal (STOP and KILL) sent by a
>> process to its pid namespace init process ?  Then, all other signals
>> should be handled appropriately by the pid namespace init.
>
> Yes, I think you are probably right, this should be enough in
> practice. After all, only root can send the signal to /sbin/init. On
> my machine, /proc/1/status shows that init doesn't have a handler for
> non-ignored SIGUNUSED == 31, though.
>
> But who knows? The kernel promises some guarantees, it is not good to
> break them.  Perhaps some strange non-standard environment may suffer.

In this case "strange non-standard environments" would mean anyone
running the 'upstart' daemon from recent Ubuntu -- it depends on the
current kernel semantics.

Regards,
        Daniel
-- 
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