[PATCH v2 1/5] KVM: Let vcpu structure alignment be determined at runtime

[Avi Kivity <avi@redhat.com>]

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>
---
 arch/ia64/kvm/vmm.c       |    2 +-
 arch/powerpc/kvm/44x.c    |    2 +-
 arch/powerpc/kvm/book3s.c |    3 ++-
 arch/powerpc/kvm/e500.c   |    2 +-
 arch/s390/kvm/kvm-s390.c  |    2 +-
 arch/x86/kvm/svm.c        |    2 +-
 arch/x86/kvm/vmx.c        |    3 ++-
 include/linux/kvm_host.h  |    2 +-
 virt/kvm/kvm_main.c       |    7 ++++---
 9 files changed, 14 insertions(+), 11 deletions(-)

diff --git a/arch/ia64/kvm/vmm.c b/arch/ia64/kvm/vmm.c
index 7a62f75..f0b9cac 100644
--- a/arch/ia64/kvm/vmm.c
+++ b/arch/ia64/kvm/vmm.c
@@ -51,7 +51,7 @@ static int __init  kvm_vmm_init(void)
 	vmm_fpswa_interface = fpswa_interface;
 
 	/*Register vmm data to kvm side*/
-	return kvm_init(&vmm_info, 1024, THIS_MODULE);
+	return kvm_init(&vmm_info, 1024, 0, THIS_MODULE);
 }
 
 static void __exit kvm_vmm_exit(void)
diff --git a/arch/powerpc/kvm/44x.c b/arch/powerpc/kvm/44x.c
index 689a57c..73c0a3f 100644
--- a/arch/powerpc/kvm/44x.c
+++ b/arch/powerpc/kvm/44x.c
@@ -147,7 +147,7 @@ static int __init kvmppc_44x_init(void)
 	if (r)
 		return r;
 
-	return kvm_init(NULL, sizeof(struct kvmppc_vcpu_44x), THIS_MODULE);
+	return kvm_init(NULL, sizeof(struct kvmppc_vcpu_44x), 0, THIS_MODULE);
 }
 
 static void __exit kvmppc_44x_exit(void)
diff --git a/arch/powerpc/kvm/book3s.c b/arch/powerpc/kvm/book3s.c
index 28e785f..11f226f 100644
--- a/arch/powerpc/kvm/book3s.c
+++ b/arch/powerpc/kvm/book3s.c
@@ -1385,7 +1385,8 @@ int __kvmppc_vcpu_run(struct kvm_run *kvm_run, struct kvm_vcpu *vcpu)
 
 static int kvmppc_book3s_init(void)
 {
-	return kvm_init(NULL, sizeof(struct kvmppc_vcpu_book3s), THIS_MODULE);
+	return kvm_init(NULL, sizeof(struct kvmppc_vcpu_book3s), 0,
+			THIS_MODULE);
 }
 
 static void kvmppc_book3s_exit(void)
diff --git a/arch/powerpc/kvm/e500.c b/arch/powerpc/kvm/e500.c
index 669a5c5..bc2b400 100644
--- a/arch/powerpc/kvm/e500.c
+++ b/arch/powerpc/kvm/e500.c
@@ -161,7 +161,7 @@ static int __init kvmppc_e500_init(void)
 	flush_icache_range(kvmppc_booke_handlers,
 			kvmppc_booke_handlers + max_ivor + kvmppc_handler_len);
 
-	return kvm_init(NULL, sizeof(struct kvmppc_vcpu_e500), THIS_MODULE);
+	return kvm_init(NULL, sizeof(struct kvmppc_vcpu_e500), 0, THIS_MODULE);
 }
 
 static void __init kvmppc_e500_exit(void)
diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c
index ee7c713..8093e6f 100644
--- a/arch/s390/kvm/kvm-s390.c
+++ b/arch/s390/kvm/kvm-s390.c
@@ -752,7 +752,7 @@ gfn_t unalias_gfn(struct kvm *kvm, gfn_t gfn)
 static int __init kvm_s390_init(void)
 {
 	int ret;
-	ret = kvm_init(NULL, sizeof(struct kvm_vcpu), THIS_MODULE);
+	ret = kvm_init(NULL, sizeof(struct kvm_vcpu), 0, THIS_MODULE);
 	if (ret)
 		return ret;
 
diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c
index 889f660..2511664 100644
--- a/arch/x86/kvm/svm.c
+++ b/arch/x86/kvm/svm.c
@@ -3319,7 +3319,7 @@ static struct kvm_x86_ops svm_x86_ops = {
 static int __init svm_init(void)
 {
 	return kvm_init(&svm_x86_ops, sizeof(struct vcpu_svm),
-			      THIS_MODULE);
+			__alignof__(struct vcpu_svm), THIS_MODULE);
 }
 
 static void __exit svm_exit(void)
diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c
index 875b785..2e87296 100644
--- a/arch/x86/kvm/vmx.c
+++ b/arch/x86/kvm/vmx.c
@@ -4245,7 +4245,8 @@ static int __init vmx_init(void)
 
 	set_bit(0, vmx_vpid_bitmap); /* 0 is reserved for host */
 
-	r = kvm_init(&vmx_x86_ops, sizeof(struct vcpu_vmx), THIS_MODULE);
+	r = kvm_init(&vmx_x86_ops, sizeof(struct vcpu_vmx),
+		     __alignof__(struct vcpu_vmx), THIS_MODULE);
 	if (r)
 		goto out3;
 
diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h
index ce027d5..7cb116a 100644
--- a/include/linux/kvm_host.h
+++ b/include/linux/kvm_host.h
@@ -243,7 +243,7 @@ void kvm_vcpu_uninit(struct kvm_vcpu *vcpu);
 void vcpu_load(struct kvm_vcpu *vcpu);
 void vcpu_put(struct kvm_vcpu *vcpu);
 
-int kvm_init(void *opaque, unsigned int vcpu_size,
+int kvm_init(void *opaque, unsigned vcpu_size, unsigned vcpu_align,
 		  struct module *module);
 void kvm_exit(void);
 
diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index 9ab1a77..f032806 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;
-- 
1.7.0.4