KVM: Let vcpu structure alignment be determined at runtime

vmx and svm vcpus have different contents and therefore may have different
alignmment requirements.  Let each specify its required alignment.

Signed-off-by: Avi Kivity <avi@redhat.com>

1 files changed, 4 insertions, 3 deletions

diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index 9ab1a77941ef..f032806a212f 100644
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -2178,7 +2178,7 @@ static void kvm_sched_out(struct preempt_notifier *pn,
         kvm_arch_vcpu_put(vcpu);
 }
 
-int kvm_init(void *opaque, unsigned int vcpu_size,
+int kvm_init(void *opaque, unsigned vcpu_size, unsigned vcpu_align,
                   struct module *module)
 {
         int r;
@@ -2228,8 +2228,9 @@ int kvm_init(void *opaque, unsigned int vcpu_size,
                 goto out_free_4;
 
         /* A kmem cache lets us meet the alignment requirements of fx_save. */
-        kvm_vcpu_cache = kmem_cache_create("kvm_vcpu", vcpu_size,
-                                           __alignof__(struct kvm_vcpu),
+        if (!vcpu_align)
+                vcpu_align = __alignof__(struct kvm_vcpu);
+        kvm_vcpu_cache = kmem_cache_create("kvm_vcpu", vcpu_size, vcpu_align,
                                            0, NULL);
         if (!kvm_vcpu_cache) {
                 r = -ENOMEM;