In place kexec

[Eric W. Biederman]

David Woodhouse <dwmw2 at infradead.org> writes:

> On Fri, 30 Jul 2010, Vivek Goyal wrote:
>
>> So what happens if we tear down the mapping while DMA is on.
>
> The DMA gets blocked, and you don't have to worry about whether the device was
> shut down cleanly or not. The device may be unhappy, but when the new kernel's
> driver loads and reinitialises it, all should be forgiven.

Assuming IOMMU page faults don't cause pain.  I seem to remember that
also being a nasty issue.

Eric