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This ensures guest page >>> table entries for shared DAX buffers are explicitly marked as decrypted, >>> preventing memory encryption faults when accessing host-shared DAX memory. >>> >>> Signed-off-by: Punit Salian >>> --- >>> fs/fuse/dax.c | 1 + >>> 1 file changed, 1 insertion(+) >>> >>> diff --git a/fs/fuse/dax.c b/fs/fuse/dax.c >>> index a15c464c8d19..00e316a7f805 100644 >>> --- a/fs/fuse/dax.c >>> +++ b/fs/fuse/dax.c >>> @@ -826,6 +826,7 @@ int fuse_dax_mmap(struct file *file, struct vm_area_struct *vma) >>> file_accessed(file); >>> vma->vm_ops = &fuse_dax_vm_ops; >>> vm_flags_set(vma, VM_MIXEDMAP | VM_HUGEPAGE); >>> + vma->vm_page_prot = pgprot_decrypted(vma->vm_page_prot); For virtio-pmem on host with SEV support we addressed similar issue by marking FS DAX device memory decrypted in memremap_pages() (commit 867400af90f1, "mm/memremap.c: map FS_DAX device memory as decrypted"), since the device memory is mapped though the kernel address space there. For virtio-fs DAX we don't seem to have such a central location so VMA level handling seems reasonable fix to me. That said, I'm not entirely certain about all of the security implications in a CoCo environment, given that the host is generally considered untrusted and virtio-fs involves sharing host-backed memory with the guest. Till we get some mechanism to access this memory as encrypted, we can have this support with existing security practices for virtio-fs: Acked-by: Pankaj Gupta