diff options
| author | Peter Xu <peterx@redhat.com> | 2018-10-09 15:45:43 +0800 |
|---|---|---|
| committer | Michael S. Tsirkin <mst@redhat.com> | 2018-11-05 13:24:02 -0500 |
| commit | c28b535d083d0a263d38d9ceeada83cdae8c64f0 (patch) | |
| tree | 5d923f564c469892ab707a98dc1e86e2c75a00a8 /hw | |
| parent | 95ecd3df7815b4bc4f9a0f47e1c64d81434715aa (diff) | |
intel_iommu: handle invalid ce for shadow sync
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 <pezhang@redhat.com>
Fixes: https://bugzilla.redhat.com/show_bug.cgi?id=1627272
Signed-off-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Reviewed-by: Maxime Coquelin <maxime.coquelin@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Diffstat (limited to 'hw')
| -rw-r--r-- | hw/i386/intel_iommu.c | 17 |
1 files changed, 17 insertions, 0 deletions
diff --git a/hw/i386/intel_iommu.c b/hw/i386/intel_iommu.c index 25e54671f4..f24ebfca1c 100644 --- a/hw/i386/intel_iommu.c +++ b/hw/i386/intel_iommu.c @@ -38,6 +38,7 @@ #include "trace.h" static void vtd_address_space_refresh_all(IntelIOMMUState *s); +static void vtd_address_space_unmap(VTDAddressSpace *as, IOMMUNotifier *n); static void vtd_define_quad(IntelIOMMUState *s, hwaddr addr, uint64_t val, uint64_t wmask, uint64_t w1cmask) @@ -1066,11 +1067,27 @@ static int vtd_sync_shadow_page_table(VTDAddressSpace *vtd_as) { int ret; VTDContextEntry ce; + IOMMUNotifier *n; ret = vtd_dev_to_context_entry(vtd_as->iommu_state, pci_bus_num(vtd_as->bus), vtd_as->devfn, &ce); if (ret) { + if (ret == -VTD_FR_CONTEXT_ENTRY_P) { + /* + * It's a valid scenario to have a context entry that is + * not present. For example, when a device is removed + * from an existing domain then the context entry will be + * zeroed by the guest before it was put into another + * domain. When this happens, instead of synchronizing + * the shadow pages we should invalidate all existing + * mappings and notify the backends. + */ + IOMMU_NOTIFIER_FOREACH(n, &vtd_as->iommu) { + vtd_address_space_unmap(vtd_as, n); + } + ret = 0; + } return ret; } |