While it is true that devices with is_virtfn=1 will have an MSE that is hard-wired to 0, this is not the only case where we see this behavior -- For example some bare-metal hypervisors lack MSE bit emulation for devices not setting is_virtfn (s390). Fix this by instead checking for the newly-added PCI_DEV_FLAGS_FORCE_COMMAND_MEM flag which directly denotes the need for MSE bit emulation in vfio.
Signed-off-by: Matthew Rosato <[email protected]> Reviewed-by: Niklas Schnelle <[email protected]> --- drivers/vfio/pci/vfio_pci_config.c | 20 +++++++++++++------- 1 file changed, 13 insertions(+), 7 deletions(-) diff --git a/drivers/vfio/pci/vfio_pci_config.c b/drivers/vfio/pci/vfio_pci_config.c index d98843f..47fb3c7 100644 --- a/drivers/vfio/pci/vfio_pci_config.c +++ b/drivers/vfio/pci/vfio_pci_config.c @@ -406,7 +406,8 @@ bool __vfio_pci_memory_enabled(struct vfio_pci_device *vdev) * PF SR-IOV capability, there's therefore no need to trigger * faults based on the virtual value. */ - return pdev->is_virtfn || (cmd & PCI_COMMAND_MEMORY); + return (pdev->dev_flags & PCI_DEV_FLAGS_FORCE_COMMAND_MEM) || + (cmd & PCI_COMMAND_MEMORY); } /* @@ -520,8 +521,9 @@ static int vfio_basic_config_read(struct vfio_pci_device *vdev, int pos, count = vfio_default_config_read(vdev, pos, count, perm, offset, val); - /* Mask in virtual memory enable for SR-IOV devices */ - if (offset == PCI_COMMAND && vdev->pdev->is_virtfn) { + /* Mask in virtual memory enable */ + if ((offset == PCI_COMMAND) && + (vdev->pdev->dev_flags & PCI_DEV_FLAGS_FORCE_COMMAND_MEM)) { u16 cmd = le16_to_cpu(*(__le16 *)&vdev->vconfig[PCI_COMMAND]); u32 tmp_val = le32_to_cpu(*val); @@ -589,9 +591,11 @@ static int vfio_basic_config_write(struct vfio_pci_device *vdev, int pos, * shows it disabled (phys_mem/io, then the device has * undergone some kind of backdoor reset and needs to be * restored before we allow it to enable the bars. - * SR-IOV devices will trigger this, but we catch them later + * SR-IOV devices will trigger this - for mem enable let's + * catch this now and for io enable it will be caught later */ - if ((new_mem && virt_mem && !phys_mem) || + if ((new_mem && virt_mem && !phys_mem && + !(pdev->dev_flags & PCI_DEV_FLAGS_FORCE_COMMAND_MEM)) || (new_io && virt_io && !phys_io) || vfio_need_bar_restore(vdev)) vfio_bar_restore(vdev); @@ -1734,9 +1738,11 @@ int vfio_config_init(struct vfio_pci_device *vdev) vconfig[PCI_INTERRUPT_PIN]); vconfig[PCI_INTERRUPT_PIN] = 0; /* Gratuitous for good VFs */ - + } + if (pdev->dev_flags & PCI_DEV_FLAGS_FORCE_COMMAND_MEM) { /* - * VFs do no implement the memory enable bit of the COMMAND + * VFs and devices that set PCI_DEV_FLAGS_FORCE_COMMAND_MEM + * do not implement the memory enable bit of the COMMAND * register therefore we'll not have it set in our initial * copy of config space after pci_enable_device(). For * consistency with PFs, set the virtual enable bit here. -- 1.8.3.1
