Re: remote debugging via FireWire * __fast__ firedump!

Bernhard Kaindl
2007-12-06T16:03:18Z

On Tue, 4 Dec 2007, Andi Kleen wrote:
>
>> I have just had the guts to explore __fast__ memory dumping over
>> firewire for full-system dumps [...]
>
> Unfortunately it won't work for >3GB or so AFAIK.

Yes we seem to be limited to 4GB mostly, with 3G mem hole, it's 3GB.

>> Afterwards, the victim was dead (I excluded the low MB of memory,
>> so something else must have caused this), at least the start of
>
> Did you run into the PCI memory hole below 4GB?

Thanks, that was it most likely. I checked and haw that I did
read a 32MB reserved area just below 2GB.

> I suppose the best way would be to require a System.map and
> then read e820.nr_map/e820.map[] and only dump real memory.

Yes, good idea!
Bernhard