On 03/02/2017 02:46 PM, Auger Eric wrote:
Hi,
On 02/03/2017 13:38, Mian Yousaf Kaukab wrote:
On 03/02/2017 11:24 AM, Auger Eric wrote:
Hi,
On 02/03/2017 11:01, Mian Yousaf Kaukab wrote:
Check only if irq domains are available.
Signed-off-by: Mian Yousaf Kaukab <yousaf.kaukab@xxxxxxxx>
---
drivers/vfio/vfio_iommu_type1.c | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)
diff --git a/drivers/vfio/vfio_iommu_type1.c
b/drivers/vfio/vfio_iommu_type1.c
index bd6f293c4ebd..e3ed50e40ead 100644
--- a/drivers/vfio/vfio_iommu_type1.c
+++ b/drivers/vfio/vfio_iommu_type1.c
@@ -1287,8 +1287,9 @@ static int vfio_iommu_type1_attach_group(void
*iommu_data,
INIT_LIST_HEAD(&domain->group_list);
list_add(&group->next, &domain->group_list);
- msi_remap = resv_msi ? irq_domain_check_msi_remap() :
- iommu_capable(bus, IOMMU_CAP_INTR_REMAP);
+ msi_remap = resv_msi && IS_ENABLED(CONFIG_IRQ_DOMAIN) ?
+ irq_domain_check_msi_remap() :
+ iommu_capable(bus, IOMMU_CAP_INTR_REMAP);
Is that patch actually needed after [PATCH 1/2] irqdomain: add empty
irq_domain_check_msi_remap. irq_domain_check_msi_remap() should be
defined and if you follow my suggestion, would return false. Anyway in
your case resv_msi should be false.
I agree its an overkill if resv_msi is guaranteed to be false. What I am
unsure about is that, if iommu have IOMMU_RESV_MSI regions that would
mean that irq domains are selected in the build. If this is not
guaranteed, then we need to add this check.
Currently only ARM SMMUs advertise IOMMU_RESV_MSI regions. If attempting
to do passthrough on an ARM platform not implementing IRQ_DOMAIN the
unsafe IRQ assignment mode would need to be chosen (if
irq_domain_check_msi_remap() returns false as discussed before). Anyway
checking the interrupt remapping capability on IOMMU side would report
false as well since the capability is not exposed by ARM SMMU anymore.OK I will drop this patch. We get a warning anyway in case the
capability is checked from the wrong place.
BR,
Yousaf
