Re: [Qemu-devel] [PATCH v2 2/2] target/i386: sev: Do not pin the ram device memory region

[Alex Williamson]

On Mon, 4 Feb 2019 22:23:40 +
"Singh, Brijesh"  wrote:

> The RAM device presents a memory region that should be handled
> as an IO region and should not be pinned.
> 
> In the case of the vfio-pci, RAM device represents a MMIO BAR
> and the memory region is not backed by pages hence
> KVM_MEMORY_ENCRYPT_REG_REGION fails to lock the memory range.
> 
> Fixes: https://bugzilla.redhat.com/show_bug.cgi?id=1667249
> Cc: Alex Williamson 
> Cc: Paolo Bonzini 
> Signed-off-by: Brijesh Singh 
> ---
>  target/i386/sev.c | 11 +++
>  1 file changed, 11 insertions(+)
> 
> diff --git a/target/i386/sev.c b/target/i386/sev.c
> index 20b2d325d8..cd77f6b5d4 100644
> --- a/target/i386/sev.c
> +++ b/target/i386/sev.c
> @@ -131,6 +131,17 @@ sev_ram_block_added(RAMBlockNotifier *n, void *host, 
> size_t size)
>  {
>  int r;
>  struct kvm_enc_region range;
> +ram_addr_t offset;
> +MemoryRegion *mr;
> +
> +/*
> + * The RAM device presents a memory region that should be treated
> + * as IO region and should not be pinned.
> + */
> +mr = memory_region_from_host(host, );
> +if (mr && memory_region_is_ram_device(mr)) {
> +return;
> +}
>  
>  range.addr = (__u64)(unsigned long)host;
>  range.size = size;

Reviewed-by: Alex Williamson 

[Qemu-devel] [PATCH v2 2/2] target/i386: sev: Do not pin the ram device memory region

[Singh, Brijesh]

The RAM device presents a memory region that should be handled
as an IO region and should not be pinned.

In the case of the vfio-pci, RAM device represents a MMIO BAR
and the memory region is not backed by pages hence
KVM_MEMORY_ENCRYPT_REG_REGION fails to lock the memory range.

Fixes: https://bugzilla.redhat.com/show_bug.cgi?id=1667249
Cc: Alex Williamson 
Cc: Paolo Bonzini 
Signed-off-by: Brijesh Singh 
---
 target/i386/sev.c | 11 +++
 1 file changed, 11 insertions(+)

diff --git a/target/i386/sev.c b/target/i386/sev.c
index 20b2d325d8..cd77f6b5d4 100644
--- a/target/i386/sev.c
+++ b/target/i386/sev.c
@@ -131,6 +131,17 @@ sev_ram_block_added(RAMBlockNotifier *n, void *host, 
size_t size)
 {
 int r;
 struct kvm_enc_region range;
+ram_addr_t offset;
+MemoryRegion *mr;
+
+/*
+ * The RAM device presents a memory region that should be treated
+ * as IO region and should not be pinned.
+ */
+mr = memory_region_from_host(host, );
+if (mr && memory_region_is_ram_device(mr)) {
+return;
+}
 
 range.addr = (__u64)(unsigned long)host;
 range.size = size;
-- 
2.17.1