[PATCH v3 36/70] kvm/tdx: Don't complain when converting vMMIO region to shared

Xiaoyao Li
2023-11-15T07:20:02Z

From: Isaku Yamahata <isaku.yamahata@intel.com>

Because vMMIO region needs to be shared region, guest TD may explicitly
convert such region from private to shared. Don't complain such
conversion.

Signed-off-by: Isaku Yamahata <isaku.yamahata@intel.com>
Signed-off-by: Xiaoyao Li <xiaoyao.li@intel.com>
---
accel/kvm/kvm-all.c | 25 ++++++++++++++++++++-----
1 file changed, 20 insertions(+), 5 deletions(-)

diff --git a/accel/kvm/kvm-all.c b/accel/kvm/kvm-all.c
index 316690d113d0..5e862db4af41 100644
--- a/accel/kvm/kvm-all.c
+++ b/accel/kvm/kvm-all.c
@@ -2933,17 +2933,19 @@ static int kvm_convert_memory(hwaddr start, hwaddr size, bool to_private)
{
MemoryRegionSection section;
ram_addr_t offset;
+ MemoryRegion *mr;
RAMBlock *rb;
void *addr;
int ret = -1;

trace_kvm_convert_memory(start, size, to_private ? "shared_to_private" : "private_to_shared");
section = memory_region_find(get_system_memory(), start, size);
- if (!section.mr) {
+ mr = section.mr;
+ if (!mr) {
return ret;
}

- if (memory_region_has_guest_memfd(section.mr)) {
+ if (memory_region_has_guest_memfd(mr)) {
if (to_private) {
ret = kvm_set_memory_attributes_private(start, size);
} else {
@@ -2965,9 +2967,22 @@ static int kvm_convert_memory(hwaddr start, hwaddr size, bool to_private)
*/
ram_block_convert_range(rb, offset, size, to_private);
} else {
- warn_report("Convert non guest_memfd backed memory region "
- "(0x%"HWADDR_PRIx" ,+ 0x%"HWADDR_PRIx") to %s",
- start, size, to_private ? "private" : "shared");
+ /*
+ * Because vMMIO region must be shared, guest TD may convert vMMIO
+ * region to shared explicitly. Don't complain such case. See
+ * memory_region_type() for checking if the region is MMIO region.
+ */
+ if (!to_private &&
+ !memory_region_is_ram(mr) &&
+ !memory_region_is_ram_device(mr) &&
+ !memory_region_is_rom(mr) &&
+ !memory_region_is_romd(mr)) {
+ ret = 0;
+ } else {
+ warn_report("Convert non guest_memfd backed memory region "
+ "(0x%"HWADDR_PRIx" ,+ 0x%"HWADDR_PRIx") to %s",
+ start, size, to_private ? "private" : "shared");
+ }
}

memory_region_unref(section.mr);
--
2.34.1