Re: [Qemu-devel] [PATCH] intel_iommu: handle invalid ce for shadow sync

[Peter Xu]

On Thu, Sep 13, 2018 at 03:55:17PM +0800, Peter Xu wrote:
> There are two callers for vtd_sync_shadow_page_table_range(), one
> provided a valid context entry and one not.  Move that fetching
> operation into the caller vtd_sync_shadow_page_table() where we need to
> fetch the context entry.
> 
> Meanwhile, we should handle VTD_FR_CONTEXT_ENTRY_P properly when
> synchronizing shadow page tables.  Having invalid context entry there is
> perfectly valid when we move a device out of an existing domain.  When
> that happens, instead of posting an error we invalidate the whole region.
> 
> Without this patch, QEMU will crash if we do these steps:
> 
> (1) start QEMU with VT-d IOMMU and two 10G NICs (ixgbe)
> (2) bind the NICs with vfio-pci in the guest
> (3) start testpmd with the NICs applied
> (4) stop testpmd
> (5) rebind the NIC back to ixgbe kernel driver
> 
> The patch should fix it.

Ping?

Regards,

-- 
Peter Xu