Re: [PATCH 3/4] Revert "x86: disable IOMMUs on kernel crash"

Joerg Roedel
2010-04-04T08:53:40Z

On Sun, Apr 04, 2010 at 09:24:30AM +0200, Bernhard Walle wrote:
> Am 03.04.10 19:49, schrieb Eric W. Biederman:
> > Not a problem. We require a lot of things of the kdump kernel,
> > and it is immediately apparent in a basic sanity test.
>
> Also, in most cases (for example: distribution kernels), the kdump
> kernel nowadays is identical to the running kernel. So, if the running
> kernel has IOMMU support, the kdump kernel also has.

Yes, I know. But is that a requirement for kexec? If not we still
potentially have this problem. It is a smaller problem than
data-corruption caused by in-flight dma because most
people^Wdistributions indeed use the same kernel for normal boot and
kexec, thats true.

Joerg