From: Ankit Agrawal <ankita@xxxxxxxxxx> The code to map the MMIO in S2 as NormalNC is enabled when conveyed that the device is WC safe using a new flag VM_ALLOW_ANY_UNCACHED. Make vfio-pci set the VM_ALLOW_ANY_UNCACHED flag. This could be extended to other devices in the future once that is deemed safe. Suggested-by: Catalin Marinas <catalin.marinas@xxxxxxx> Acked-by: Jason Gunthorpe <jgg@xxxxxxxxxx> Acked-by: Catalin Marinas <catalin.marinas@xxxxxxx> Signed-off-by: Ankit Agrawal <ankita@xxxxxxxxxx> --- drivers/vfio/pci/vfio_pci_core.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/drivers/vfio/pci/vfio_pci_core.c b/drivers/vfio/pci/vfio_pci_core.c index 1cbc990d42e0..eba2146202f9 100644 --- a/drivers/vfio/pci/vfio_pci_core.c +++ b/drivers/vfio/pci/vfio_pci_core.c @@ -1862,8 +1862,12 @@ int vfio_pci_core_mmap(struct vfio_device *core_vdev, struct vm_area_struct *vma /* * See remap_pfn_range(), called from vfio_pci_fault() but we can't * change vm_flags within the fault handler. Set them now. + * + * Set an additional flag VM_ALLOW_ANY_UNCACHED to convey kvm that + * the device is wc safe. */ - vm_flags_set(vma, VM_IO | VM_PFNMAP | VM_DONTEXPAND | VM_DONTDUMP); + vm_flags_set(vma, VM_ALLOW_ANY_UNCACHED | VM_IO | VM_PFNMAP | + VM_DONTEXPAND | VM_DONTDUMP); vma->vm_ops = &vfio_pci_mmap_ops; return 0; -- 2.34.1
