RE: [PATCH v8 7/9] hw/i386/q35: Set virtio-iommu aw-bits default value to 39

[Duan, Zhenzhong]

>-----Original Message-----
>From: Eric Auger <eric.auger@redhat.com>
>Subject: [PATCH v8 7/9] hw/i386/q35: Set virtio-iommu aw-bits default
>value to 39
>
>Currently the default input range can extend to 64 bits. On x86,
>when the virtio-iommu protects vfio devices, the physical iommu
>may support only 39 bits. Let's set the default to 39, as done
>for the intel-iommu.
>
>We use hw_compat_8_2 to handle the compatibility for machines
>before 9.0 which used to have a virtio-iommu default input range
>of 64 bits.
>
>Of course if aw-bits is set from the command line, the default
>is overriden.
>
>Signed-off-by: Eric Auger <eric.auger@redhat.com>

Reviewed-by: Zhenzhong Duan <zhenzhong.duan@intel.com>

Thanks
Zhenzhong

>
>---
>
>v6 -> v7:
>- use static pc_q35_compat_defaults
>- remove spurious header addition
>- s/32/UINT32_MAX in the qtest
>
>v5 -> v6:
>- split pc/arm settings
>
>v3 -> v4:
>- update the qos test to relax the check on the max input IOVA
>
>v2 -> v3:
>- collected Zhenzhong's R-b
>- use &error_abort instead of NULL error handle
>  on object_property_get_uint() call (Cédric)
>- use VTD_HOST_AW_39BIT (Cédric)
>
>v1 -> v2:
>- set aw-bits to 48b on ARM
>- use hw_compat_8_2 to handle the compat for older machines
>  which used 64b as a default
>---
> hw/core/machine.c               | 1 +
> hw/i386/pc_q35.c                | 9 +++++++++
> tests/qtest/virtio-iommu-test.c | 2 +-
> 3 files changed, 11 insertions(+), 1 deletion(-)
>
>diff --git a/hw/core/machine.c b/hw/core/machine.c
>index 6bd09d4592..4b89172d1c 100644
>--- a/hw/core/machine.c
>+++ b/hw/core/machine.c
>@@ -35,6 +35,7 @@
>
> GlobalProperty hw_compat_8_2[] = {
>     { TYPE_VIRTIO_IOMMU_PCI, "granule", "4k" },
>+    { TYPE_VIRTIO_IOMMU_PCI, "aw-bits", "64" },
> };
> const size_t hw_compat_8_2_len = G_N_ELEMENTS(hw_compat_8_2);
>
>diff --git a/hw/i386/pc_q35.c b/hw/i386/pc_q35.c
>index 45a4102e75..1e7464d39a 100644
>--- a/hw/i386/pc_q35.c
>+++ b/hw/i386/pc_q35.c
>@@ -45,6 +45,7 @@
> #include "hw/i386/pc.h"
> #include "hw/i386/amd_iommu.h"
> #include "hw/i386/intel_iommu.h"
>+#include "hw/virtio/virtio-iommu.h"
> #include "hw/display/ramfb.h"
> #include "hw/ide/pci.h"
> #include "hw/ide/ahci-pci.h"
>@@ -63,6 +64,12 @@
> /* ICH9 AHCI has 6 ports */
> #define MAX_SATA_PORTS     6
>
>+static GlobalProperty pc_q35_compat_defaults[] = {
>+    { TYPE_VIRTIO_IOMMU_PCI, "aw-bits", "39" },
>+};
>+static const size_t pc_q35_compat_defaults_len =
>+    G_N_ELEMENTS(pc_q35_compat_defaults);
>+
> struct ehci_companions {
>     const char *name;
>     int func;
>@@ -356,6 +363,8 @@ static void pc_q35_machine_options(MachineClass
>*m)
>     machine_class_allow_dynamic_sysbus_dev(m,
>TYPE_INTEL_IOMMU_DEVICE);
>     machine_class_allow_dynamic_sysbus_dev(m, TYPE_RAMFB_DEVICE);
>     machine_class_allow_dynamic_sysbus_dev(m, TYPE_VMBUS_BRIDGE);
>+    compat_props_add(m->compat_props,
>+                     pc_q35_compat_defaults, pc_q35_compat_defaults_len);
> }
>
> static void pc_q35_9_0_machine_options(MachineClass *m)
>diff --git a/tests/qtest/virtio-iommu-test.c b/tests/qtest/virtio-iommu-test.c
>index 068e7a9e6c..afb225971d 100644
>--- a/tests/qtest/virtio-iommu-test.c
>+++ b/tests/qtest/virtio-iommu-test.c
>@@ -34,7 +34,7 @@ static void pci_config(void *obj, void *data,
>QGuestAllocator *t_alloc)
>     uint8_t bypass = qvirtio_config_readb(dev, 36);
>
>     g_assert_cmpint(input_range_start, ==, 0);
>-    g_assert_cmphex(input_range_end, ==, UINT64_MAX);
>+    g_assert_cmphex(input_range_end, >=, UINT32_MAX);
>     g_assert_cmpint(domain_range_start, ==, 0);
>     g_assert_cmpint(domain_range_end, ==, UINT32_MAX);
>     g_assert_cmpint(bypass, ==, 1);
>--
>2.41.0