Drivers: hv: Explicitly request decrypted in vmap_pfn() calls
authorMichael Kelley <mikelley@microsoft.com>
Sun, 26 Mar 2023 13:51:58 +0000 (06:51 -0700)
committerBorislav Petkov (AMD) <bp@alien8.de>
Mon, 27 Mar 2023 06:46:43 +0000 (08:46 +0200)
Update vmap_pfn() calls to explicitly request that the mapping
be for decrypted access to the memory.  There's no change in
functionality since the PFNs passed to vmap_pfn() are above the
shared_gpa_boundary, implicitly producing a decrypted mapping.
But explicitly requesting "decrypted" allows the code to work
before and after changes that cause vmap_pfn() to mask the
PFNs to being below the shared_gpa_boundary.

Signed-off-by: Michael Kelley <mikelley@microsoft.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Reviewed-by: Tianyu Lan <Tianyu.Lan@microsoft.com>
Link: https://lore.kernel.org/r/1679838727-87310-4-git-send-email-mikelley@microsoft.com
arch/x86/hyperv/ivm.c
drivers/hv/ring_buffer.c

index f33c67e..5648efb 100644 (file)
@@ -343,7 +343,7 @@ void *hv_map_memory(void *addr, unsigned long size)
                pfns[i] = vmalloc_to_pfn(addr + i * PAGE_SIZE) +
                        (ms_hyperv.shared_gpa_boundary >> PAGE_SHIFT);
 
-       vaddr = vmap_pfn(pfns, size / PAGE_SIZE, PAGE_KERNEL_IO);
+       vaddr = vmap_pfn(pfns, size / PAGE_SIZE, pgprot_decrypted(PAGE_KERNEL));
        kfree(pfns);
 
        return vaddr;
index c6692fd..2111e97 100644 (file)
@@ -211,7 +211,7 @@ int hv_ringbuffer_init(struct hv_ring_buffer_info *ring_info,
 
                ring_info->ring_buffer = (struct hv_ring_buffer *)
                        vmap_pfn(pfns_wraparound, page_cnt * 2 - 1,
-                                PAGE_KERNEL);
+                                pgprot_decrypted(PAGE_KERNEL));
                kfree(pfns_wraparound);
 
                if (!ring_info->ring_buffer)