Messages in this thread | | | Date | Sat, 9 Nov 2002 22:21:04 +0100 | From | Pavel Machek <> | Subject | Re: [lkcd-devel] Re: What's left over. |
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Hi!
> > Yes, we are putting [MCORE] in as one of the alternative dump targets > > available. > > Great ! > > > Its not quite ready yet and we need something like kexec to be > > available which we can use on Intel systems to achieve the softboot > > (the acceptance status of that still doesn't seem to be clear), > > Yes, I've just checked with Eric, and he hasn't received any > indication from Linus so far. I posted a reminder to linux-kernel. > I'd really hate to see kexec miss 2.6. > > > Why do we even consider the other options when we are doing > > this already ? Well, as we discussed earlier there's non-disruptive > > dumps for one, where this wouldn't work. > > But they're very different anyway, aren't they ? I mean, you could > even implement them (well, almost) from user space, with today's > kernels. > > > The other is that before overwriting > > memory we need to be able to stop all activity in the system for certain > > (system may appear hung/locked up) and I'm not fully certain about > > how to do this for all environments. Maybe an answer lies in > > rethinking some parts of the algorithm a bit. > > This is certainly the hairiest part, yes. I think we have about > four types of devices/elements to worry about: > > - those that just sit there, and never talk unless spoken to > - those that may generate interrupts > - those that DMA if you ask them nicely > - those that DMA when they feel like it (e.g. copy an incoming > network packet to the next buffer in the free list) > > The latter are the real problem. I see the following possibilities > for dealing with them: > > - faith-based computing: pray that nothing bad will befall your > system :-) > - de-activate them individually. There should be a lot of work > that can be shared with power management. And that's one of > the reasons why I think the memory target should be available > early, or convergence will take forever.
I have very similar problem in swsusp (need to deactivate DMA devices), and driverfs^H^H^H^H^Hsysfs framework seems to be suitable for that.
Pavel -- Worst form of spam? Adding advertisment signatures ala sourceforge.net. What goes next? Inserting advertisment *into* email? - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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