Re: Back to the future.

Rafael J. Wysocki
2007-04-27T22:00:50Z

On Friday, 27 April 2007 23:44, Linus Torvalds wrote:
>
> On Fri, 27 Apr 2007, Rafael J. Wysocki wrote:
> >
> > Why do you think that keeping the user space frozen after 'snapshot' is a bad
> > idea? I think that solves many of the problems you're discussing.
>
> It makes it harder to debug (wouldn't it be *nice* to just ssh in, and do
>
> gdb -p <snapshotter>
>
> when something goes wrong?) but we also *depend* on user space for various
> things (the same way we depend on kernel threads, and why it has been such
> a total disaster to try to freeze the kernel threads too!).

We're freezing many of them just fine. ;-)

> For example, if you want to do graphical stuff, just using X would be quite
> nice, wouldn't it?

Yes, it would, but as long as we can't protect mounted filesystems from being
touched, it's just dangerous to let the user space run at that point.

> But I do agree that doing everythign in the kernel is likely to just be a
> hell of a lot simpler for everybody.

:-)

Greetings,
Rafael