>>> On 21.02.19 at 23:08, wrote:
> It's unsafe to disable IOMMU on a live system which is the case
> if we're crashing since remapping hardware doesn't usually know what
> to do with ongoing bus transactions and frequently raises NMI/MCE/SMI,
> etc. (depends on the firmware configuration) to
On 22/02/2019 12:34, Jan Beulich wrote:
On 21.02.19 at 23:08, wrote:
>> Modern Linux kernels taught to copy all the necessary DMAR/IR tables
>> following kexec from the previous kernel (Xen in our case) - so it's
>> currently normal to keep IOMMU enabled. It might require minor changes to
>>
>>> On 21.02.19 at 23:08, wrote:
> Modern Linux kernels taught to copy all the necessary DMAR/IR tables
> following kexec from the previous kernel (Xen in our case) - so it's
> currently normal to keep IOMMU enabled. It might require minor changes to
> kdump command line that enables IOMMU
It's unsafe to disable IOMMU on a live system which is the case
if we're crashing since remapping hardware doesn't usually know what
to do with ongoing bus transactions and frequently raises NMI/MCE/SMI,
etc. (depends on the firmware configuration) to signal these abnormalities.
This, in turn,
