On 3/23/2024 2:11 AM, Paolo Bonzini wrote:
From: Xiaoyao Li <[email protected]>
KVM side leaves the memory to shared by default, while may incur the
/s/while/which/
fix typo from myself.
overhead of paging conversion on the first visit of each page. Because
the expectation is that page is likely to private for the VMs that
require private memory (has guest memfd).
Explicitly set the memory to private when memory region has valid
guest memfd backend.
Signed-off-by: Xiaoyao Li <[email protected]>
Signed-off-by: Michael Roth <[email protected]>
Message-ID: <[email protected]>
Signed-off-by: Paolo Bonzini <[email protected]>
---
accel/kvm/kvm-all.c | 10 ++++++++++
1 file changed, 10 insertions(+)
diff --git a/accel/kvm/kvm-all.c b/accel/kvm/kvm-all.c
index 7fbaf31cbaf..56b17cbd8aa 100644
--- a/accel/kvm/kvm-all.c
+++ b/accel/kvm/kvm-all.c
@@ -1430,6 +1430,16 @@ static void kvm_set_phys_mem(KVMMemoryListener *kml,
strerror(-err));
abort();
}
+
+ if (memory_region_has_guest_memfd(mr)) {
+ err = kvm_set_memory_attributes_private(start_addr, slot_size);
+ if (err) {
+ error_report("%s: failed to set memory attribute private:
%s\n",
+ __func__, strerror(-err));
+ exit(1);
+ }
+ }
+
start_addr += slot_size;
ram_start_offset += slot_size;
ram += slot_size;
