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From: Jason Gunthorpe <jgg@nvidia.com>
Date: Thu, 5 Nov 2020 12:34:58 -0400
Subject: vfio-pci: Use io_remap_pfn_range() for PCI IO memory
Git-commit: 7b06a56d468b756ad6bb43ac21b11e474ebc54a0
Patch-mainline: v5.11-rc1
References: bsc#1181231

commit f8f6ae5d077a ("mm: always have io_remap_pfn_range() set
pgprot_decrypted()") allows drivers using mmap to put PCI memory mapped
BAR space into userspace to work correctly on AMD SME systems that default
to all memory encrypted.

Since vfio_pci_mmap_fault() is working with PCI memory mapped BAR space it
should be calling io_remap_pfn_range() otherwise it will not work on SME
systems.

Fixes: 11c4cd07ba11 ("vfio-pci: Fault mmaps to enable vma tracking")
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Acked-by: Peter Xu <peterx@redhat.com>
Tested-by: Tom Lendacky <thomas.lendacky@amd.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Acked-by: Joerg Roedel <jroedel@suse.de>
---
 drivers/vfio/pci/vfio_pci.c |    4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

--- a/drivers/vfio/pci/vfio_pci.c
+++ b/drivers/vfio/pci/vfio_pci.c
@@ -1356,8 +1356,8 @@ static int vfio_pci_mmap_fault(struct vm
 
 	mutex_unlock(&vdev->vma_lock);
 
-	if (remap_pfn_range(vma, vma->vm_start, vma->vm_pgoff,
-			    vma->vm_end - vma->vm_start, vma->vm_page_prot))
+	if (io_remap_pfn_range(vma, vma->vm_start, vma->vm_pgoff,
+			       vma->vm_end - vma->vm_start, vma->vm_page_prot))
 		ret = VM_FAULT_SIGBUS;
 
 up_out: