Hi,
On 15/6/26 22:48, Nathan Chen wrote:
From: Nathan Chen <[email protected]>
Emit a warning when ats=on is requested but the physical device does not
advertise ATS, since ATS cannot be exposed to the guest in this case.
Signed-off-by: Nathan Chen <[email protected]>
---
hw/vfio/pci.c | 7 +++++++
1 file changed, 7 insertions(+)
diff --git a/hw/vfio/pci.c b/hw/vfio/pci.c
index 0f592ada89..49ba6813ee 100644
--- a/hw/vfio/pci.c
+++ b/hw/vfio/pci.c
@@ -2592,6 +2592,7 @@ static void vfio_add_ext_cap(VFIOPCIDevice *vdev, bool
ats_needed)
{
PCIDevice *pdev = PCI_DEVICE(vdev);
bool pasid_cap_added = false;
+ bool ats_cap_present = false;
Error *err = NULL;
^^^^^^^^^^
uint32_t header;
uint16_t cap_id, next, size;
@@ -2680,6 +2681,7 @@ static void vfio_add_ext_cap(VFIOPCIDevice *vdev, bool
ats_needed)
pcie_add_capability(pdev, cap_id, cap_ver, next, size);
break;
case PCI_EXT_CAP_ID_ATS:
+ ats_cap_present = true;
/*
* If ATS is requested and supported according to the kernel, add
* the ATS capability. If not supported according to the kernel or
@@ -2699,6 +2701,11 @@ static void vfio_add_ext_cap(VFIOPCIDevice *vdev, bool
ats_needed)
error_report_err(err);
^^^^^^^^^^^^^^^^
}
+ if (vdev->ats == ON_OFF_AUTO_ON && !ats_cap_present) {
+ warn_report("vfio-pci: ats=on requested, but host device has no "
+ "ATS extended capability");
+ }
At a quick glance vfio_pci_add_capabilities() should pass its @errp
to vfio_add_ext_cap() so the latter can propagate any error instead
of calling error_report_err() or warn_report(). I note this is
pre-existing and could be cleaned later, IMHO the sooner the better
but up to the maintainers.
Regards,
Phil.
