Re: [GSoC] Remote kernel debugging over Ethernet

[Thor Lancelot Simon <tls%rek.tjls.com@localhost>]

On Thu, Mar 26, 2009 at 10:28:14AM +0100, Manuel Bouyer wrote:
> On Wed, Mar 25, 2009 at 11:01:21PM +0200, Jordan Gordeev wrote:
> >[...]
> > One important question to ask is what the *goal* of kernel debugging  
> > over Ethernet is. There are virtualization solutions that can be used to  
> > debug a kernel without hangs and crashes. Some of them can offer access  
> > to kernel memory while the kernel is in a very "crashed" state. What  
> > can't be debugged with virtualization is only 1) device drivers for real  
> > hardware,
> 
> A lot can be done with Xen and PCI pass-though (it can even expose
> otherwise-hidden bugs because it's more picky about bus_dma(9) use).
> Unfortunably this doesn't work well for pcmcia or cardbus devices.

But our Xen DomU kernels still can't be attached to GDB, right?

I spent a couple of hours last week trying to pass through PCI
devices to a HVM domain, so I could do exactly what you seem to be
suggesting.  I could not get it to work -- it looked
like qemu-dm would have to be built with some PCI library that only
understoond Linux.  :-/

-- 
Thor Lancelot Simon                                        
tls%rek.tjls.com@localhost
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