Add a print explaining why vhost_vdpa_alloc_domain failed if the device
is not IOMMU cache coherent capable.

Without this print, we have no hint why the operation failed.

For example:

$ virsh start <domain>
        error: Failed to start domain <domain>
        error: Unable to open '/dev/vhost-vdpa-<idx>' for vdpa device:
               Unknown error 524

Suggested-by: Eugenio Perez Martin <epere...@redhat.com>
Signed-off-by: Alvaro Karsz <alvaro.ka...@solid-run.com>

---
v2:
        - replace dev_err with dev_warn_once.

 drivers/vhost/vdpa.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/drivers/vhost/vdpa.c b/drivers/vhost/vdpa.c
index 23db92388393..135f8aa70fb2 100644
--- a/drivers/vhost/vdpa.c
+++ b/drivers/vhost/vdpa.c
@@ -1151,8 +1151,11 @@ static int vhost_vdpa_alloc_domain(struct vhost_vdpa *v)
        if (!bus)
                return -EFAULT;
 
-       if (!device_iommu_capable(dma_dev, IOMMU_CAP_CACHE_COHERENCY))
+       if (!device_iommu_capable(dma_dev, IOMMU_CAP_CACHE_COHERENCY)) {
+               dev_warn_once(&v->dev,
+                             "Failed to allocate domain, device is not IOMMU 
cache coherent capable\n");
                return -ENOTSUPP;
+       }
 
        v->domain = iommu_domain_alloc(bus);
        if (!v->domain)
-- 
2.34.1

_______________________________________________
Virtualization mailing list
Virtualization@lists.linux-foundation.org
https://lists.linuxfoundation.org/mailman/listinfo/virtualization

Reply via email to