Hi Peter,
On 09/13/2018 09:55 AM, 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.
Reported-by: Pei Zhang<[email protected]>
Tested-by: Pei Zhang<[email protected]>
CC: Pei Zhang<[email protected]>
CC: Alex Williamson<[email protected]>
CC: Jason Wang<[email protected]>
CC: Maxime Coquelin<[email protected]>
CC: Michael S. Tsirkin<[email protected]>
CC: QEMU Stable<[email protected]>
Fixes:https://bugzilla.redhat.com/show_bug.cgi?id=1627272
It seems like a regression as it wasn't reported earlier, isn't it?
If it is, do you know what is the faulty commit?
Signed-off-by: Peter Xu<[email protected]>
---
hw/i386/intel_iommu.c | 54 ++++++++++++++++++++++++++-----------------
1 file changed, 33 insertions(+), 21 deletions(-)
Other than that, the patch looks good to me.
FWIW:
Acked-by: Maxime Coquelin <[email protected]>
Thanks,
Maxime
