Subject: Re: [PATCH] kdump: Fix for machine checkstop on DMA fault

From: Michael Ellerman <[email-masked]>
Date: Thu, 23 Mar 2006 17:06:27 +1100

On Thu, 23 Mar 2006 16:38, Olof Johansson wrote:
> On Wed, Mar 22, 2006 at 08:30:26PM -0800, Haren Myneni wrote:
> > Paul, If you are OK with this fix, please send it upstream.
> >
> > Thanks
> > Haren
> >
> > - Some machines checkstop on dma protection fault for ongoing DMA left
> > in the first kernel. Since, we do not shutdown devices before the kdump
> > boot, let them continue DMA to old kernel space.
>
> How is this solved for regular kexec, doesn't the same problem exist
> there?

The idea for normal kexec is that the kernel should have shut everything down 
properly. It's a bug if there are still DMAs going on. Hopefully.

cheers

-- 
Michael Ellerman
IBM OzLabs

wwweb: http://michael.ellerman.id.au
phone: +61 2 6212 1183 (tie line 70 21183)

We do not inherit the earth from our ancestors,
we borrow it from our children. - S.M.A.R.T Person