[tip: x86/sev] Drivers: hv: Explicitly request decrypted in vmap_pfn() calls

[tip-bot2 for Michael Kelley]

The following commit has been merged into the x86/sev branch of tip:

Commit-ID:     d33ddc92db8a61416473ff3d7f1c621c50733dc0
Gitweb:        https://git.kernel.org/tip/d33ddc92db8a61416473ff3d7f1c621c50733dc0
Author:        Michael Kelley <mikelley@xxxxxxxxxxxxx>
AuthorDate:    Sun, 26 Mar 2023 06:51:58 -07:00
Committer:     Borislav Petkov (AMD) <bp@xxxxxxxxx>
CommitterDate: Mon, 27 Mar 2023 08:46:43 +02:00

Drivers: hv: Explicitly request decrypted in vmap_pfn() calls

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@xxxxxxxxxxxxx>
Signed-off-by: Borislav Petkov (AMD) <bp@xxxxxxxxx>
Reviewed-by: Tianyu Lan <Tianyu.Lan@xxxxxxxxxxxxx>
Link: https://lore.kernel.org/r/1679838727-87310-4-git-send-email-mikelley@xxxxxxxxxxxxx
---
 arch/x86/hyperv/ivm.c    | 2 +-
 drivers/hv/ring_buffer.c | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/arch/x86/hyperv/ivm.c b/arch/x86/hyperv/ivm.c
index f33c67e..5648efb 100644
--- a/arch/x86/hyperv/ivm.c
+++ b/arch/x86/hyperv/ivm.c
@@ -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;
diff --git a/drivers/hv/ring_buffer.c b/drivers/hv/ring_buffer.c
index c6692fd..2111e97 100644
--- a/drivers/hv/ring_buffer.c
+++ b/drivers/hv/ring_buffer.c
@@ -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)