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From: Oliver Neukum <oliver@neukum.org>
To: =?utf-8?q?Bart=C5=82omiej_Zimo=C5=84?= <uzi18@o2.pl>
Subject: Re: [suspend/resume] Re: userspace notification from module
Date: Sat, 2 Jan 2010 16:11:52 +0100
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Am Samstag, 2. Januar 2010 15:27:12 schrieb Bartłomiej Zimoń:
> > Register your pids to the kernel module, e.g. via ioctl, and if the
> > (intra-kernel) notification will be delivered to your module you just
> > send a signal to your registered processes via kill_proc_info(). Guess
> > this is at least better than polling a file or sth similar.
> > 
> > I guess netlink could be the "cleaner" solution, but with more overhead?!
> > 
> 
> This looks like more simple and could be good, after all i think about sending this 
> module here to add to kernel. So if this solution could be ok i will start to code this part.

This has all sorts of implications starting with fork() and going to passing
fds over sockets and so on. It is a very bad idea. Use a standard device
and all infrastructure for getting SIGIO is in place.

	Regards
		Oliver