debian/patches/extra/0019-intel-iommu-fail-MAP-notifier-without-caching-mode.patch

   1 From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
   2 From: Jason Wang <jasowang@redhat.com>
   3 Date: Thu, 23 Feb 2023 14:59:20 +0800
   4 Subject: [PATCH] intel-iommu: fail MAP notifier without caching mode
   5
   6 Without caching mode, MAP notifier won't work correctly since guest
   7 won't send IOTLB update event when it establishes new mappings in the
   8 I/O page tables. Let's fail the IOMMU notifiers early instead of
   9 misbehaving silently.
  10
  11 Reviewed-by: Eric Auger <eric.auger@redhat.com>
  12 Tested-by: Viktor Prutyanov <viktor@daynix.com>
  13 Signed-off-by: Jason Wang <jasowang@redhat.com>
  14 Message-Id: <20230223065924.42503-2-jasowang@redhat.com>
  15 Reviewed-by: Peter Xu <peterx@redhat.com>
  16 Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
  17 Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
  18 (cherry-picked from commit b8d78277c091f26fdd64f239bc8bb7e55d74cecf)
  19 Signed-off-by: Fiona Ebner <f.ebner@proxmox.com>
  20 ---
  21  hw/i386/intel_iommu.c | 7 +++++++
  22  1 file changed, 7 insertions(+)
  23
  24 diff --git a/hw/i386/intel_iommu.c b/hw/i386/intel_iommu.c
  25 index a08ee85edf..9143376677 100644
  26 --- a/hw/i386/intel_iommu.c
  27 +++ b/hw/i386/intel_iommu.c
  28 @@ -3186,6 +3186,13 @@ static int vtd_iommu_notify_flag_changed(IOMMUMemoryRegion *iommu,
  29                           "Snoop Control with vhost or VFIO is not supported");
  30          return -ENOTSUP;
  31      }
  32 +    if (!s->caching_mode && (new & IOMMU_NOTIFIER_MAP)) {
  33 +        error_setg_errno(errp, ENOTSUP,
  34 +                         "device %02x.%02x.%x requires caching mode",
  35 +                         pci_bus_num(vtd_as->bus), PCI_SLOT(vtd_as->devfn),
  36 +                         PCI_FUNC(vtd_as->devfn));
  37 +        return -ENOTSUP;
  38 +    }
  39
  40      /* Update per-address-space notifier flags */
  41      vtd_as->notifier_flags = new;