diff mbox series

[PULL,30/63] hw/pci: Fix SR-IOV VF number calculation

Message ID a9f18342dc14c3297d802e4d06d238ac3d311706.1721607331.git.mst@redhat.com
State New
Headers show
Series [PULL,01/63] hw/virtio/virtio-crypto: Fix op_code assignment in virtio_crypto_create_asym_session | expand

Commit Message

Michael S. Tsirkin July 22, 2024, 12:17 a.m. UTC 
From: Akihiko Odaki <akihiko.odaki@daynix.com>

pci_config_get_bar_addr() had a division by vf_stride. vf_stride needs
to be non-zero when there are multiple VFs, but the specification does
not prohibit to make it zero when there is only one VF.

Do not perform the division for the first VF to avoid division by zero.

Signed-off-by: Akihiko Odaki <akihiko.odaki@daynix.com>
Message-Id: <20240715-sriov-v5-2-3f5539093ffc@daynix.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
---
 hw/pci/pci.c | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)
diff mbox series

Patch

diff --git a/hw/pci/pci.c b/hw/pci/pci.c
index bd956637bc..dbd954f1fe 100644
--- a/hw/pci/pci.c
+++ b/hw/pci/pci.c
@@ -1437,7 +1437,11 @@  static pcibus_t pci_config_get_bar_addr(PCIDevice *d, int reg,
             pci_get_word(pf->config + sriov_cap + PCI_SRIOV_VF_OFFSET);
         uint16_t vf_stride =
             pci_get_word(pf->config + sriov_cap + PCI_SRIOV_VF_STRIDE);
-        uint32_t vf_num = (d->devfn - (pf->devfn + vf_offset)) / vf_stride;
+        uint32_t vf_num = d->devfn - (pf->devfn + vf_offset);
+
+        if (vf_num) {
+            vf_num /= vf_stride;
+        }
 
         if (type & PCI_BASE_ADDRESS_MEM_TYPE_64) {
             new_addr = pci_get_quad(pf->config + bar);