From cb482cb3a305f96d8155bbeb052344dde66ad8f2 Mon Sep 17 00:00:00 2001 From: Jianfeng Tan Date: Fri, 28 Jul 2017 23:01:14 +0000 Subject: [PATCH] net/virtio: fix MAC address read When virtio-net devices are bound to uio_pci_generic, we get the wrong mac addr by virtio PMD. The wrong mac addr is a addr that is 4-byte left shift of the correct addr. It's a regression bug introduced by the cleanup patch below. The condition of if we set use_msix should be if msix is actually enabled. Only to check if there is a capability list is not enough. For example, binding a transitional device to uio_pci_device would trigger the wrong assignment of use_msix. To correct that, we also check the flags of msix capability to make sure it's enabled. Fixes: ee1843bd8907 ("net/virtio: remove redundant MSI-X detection") Cc: stable@dpdk.org Reported-by: Vipin Varghese Signed-off-by: Jianfeng Tan Acked-by: Yuanhan Liu --- drivers/net/virtio/virtio_pci.c | 15 +++++++++++++-- 1 file changed, 13 insertions(+), 2 deletions(-) diff --git a/drivers/net/virtio/virtio_pci.c b/drivers/net/virtio/virtio_pci.c index e6eda75b69..e6da6802b2 100644 --- a/drivers/net/virtio/virtio_pci.c +++ b/drivers/net/virtio/virtio_pci.c @@ -580,6 +580,8 @@ get_cfg_addr(struct rte_pci_device *dev, struct virtio_pci_cap *cap) return base + offset; } +#define PCI_MSIX_ENABLE 0x8000 + static int virtio_read_caps(struct rte_pci_device *dev, struct virtio_hw *hw) { @@ -606,8 +608,17 @@ virtio_read_caps(struct rte_pci_device *dev, struct virtio_hw *hw) break; } - if (cap.cap_vndr == PCI_CAP_ID_MSIX) - hw->use_msix = 1; + if (cap.cap_vndr == PCI_CAP_ID_MSIX) { + /* Transitional devices would also have this capability, + * that's why we also check if msix is enabled. + * 1st byte is cap ID; 2nd byte is the position of next + * cap; next two bytes are the flags. + */ + uint16_t flags = ((uint16_t *)&cap)[1]; + + if (flags & PCI_MSIX_ENABLE) + hw->use_msix = 1; + } if (cap.cap_vndr != PCI_CAP_ID_VNDR) { PMD_INIT_LOG(DEBUG, -- 2.20.1