KVM: Allocate guest memory as MAP_PRIVATE, not MAP_SHARED

(cherry picked from commit acee3c04e8208c17aad1baff99baa68d71640a19)

There is no reason to share internal memory slots with fork()ed instances.

Signed-off-by: Avi Kivity <avi@qumranet.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index a29b440..8d45d35 100644 (file)
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -4003,7 +4003,7 @@ int kvm_arch_set_memory_region(struct kvm *kvm,
                        userspace_addr = do_mmap(NULL, 0,
                                                 npages * PAGE_SIZE,
                                                 PROT_READ | PROT_WRITE,
-                                                MAP_SHARED | MAP_ANONYMOUS,
+                                                MAP_PRIVATE | MAP_ANONYMOUS,
                                                 0);
                        up_write(&current->mm->mmap_sem);