Message ID | 1666288635-72591-5-git-send-email-mikelley@microsoft.com (mailing list archive) |
---|---|
State | Superseded |
Headers | show |
Series | Add PCI pass-thru support to Hyper-V Confidential VMs | expand |
On 10/21/2022 1:57 AM, Michael Kelley wrote: > In preparation for a subsequent patch, 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 a subsequent patch > that will cause vmap_pfn() to mask the PFNs to being below the > shared_gpa_boundary. While another subsesquent patch removes the > vmap_pfn() calls entirely, this temporary tweak avoids the need > for a large patch that makes all the changes at once. > > Signed-off-by: Michael Kelley<mikelley@microsoft.com> > --- Reviewed-by: Tianyu Lan <Tianyu.Lan@microsoft.com>
diff --git a/arch/x86/hyperv/ivm.c b/arch/x86/hyperv/ivm.c index f33c67e..e8be4c2 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_NOENC)); kfree(pfns); return vaddr; diff --git a/drivers/hv/ring_buffer.c b/drivers/hv/ring_buffer.c index 59a4aa8..b4a91b1 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_NOENC)); kfree(pfns_wraparound); if (!ring_info->ring_buffer)
In preparation for a subsequent patch, 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 a subsequent patch that will cause vmap_pfn() to mask the PFNs to being below the shared_gpa_boundary. While another subsesquent patch removes the vmap_pfn() calls entirely, this temporary tweak avoids the need for a large patch that makes all the changes at once. Signed-off-by: Michael Kelley <mikelley@microsoft.com> --- arch/x86/hyperv/ivm.c | 2 +- drivers/hv/ring_buffer.c | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-)