[PATCH 2/4] KVM: nVMX: Properly pad 'struct kvm_vmx_nested_state_hdr'

From: Vitaly Kuznetsov
Date: Mon May 03 2021 - 11:09:19 EST


Eliminate the probably unwanted hole in 'struct kvm_vmx_nested_state_hdr':

Pre-patch:
struct kvm_vmx_nested_state_hdr {
__u64 vmxon_pa; /* 0 8 */
__u64 vmcs12_pa; /* 8 8 */
struct {
__u16 flags; /* 16 2 */
} smm; /* 16 2 */

/* XXX 2 bytes hole, try to pack */

__u32 flags; /* 20 4 */
__u64 preemption_timer_deadline; /* 24 8 */
};

Post-patch:
struct kvm_vmx_nested_state_hdr {
__u64 vmxon_pa; /* 0 8 */
__u64 vmcs12_pa; /* 8 8 */
struct {
__u16 flags; /* 16 2 */
} smm; /* 16 2 */
__u16 pad; /* 18 2 */
__u32 flags; /* 20 4 */
__u64 preemption_timer_deadline; /* 24 8 */
};

Signed-off-by: Vitaly Kuznetsov <vkuznets@xxxxxxxxxx>
---
arch/x86/include/uapi/asm/kvm.h | 2 ++
1 file changed, 2 insertions(+)

diff --git a/arch/x86/include/uapi/asm/kvm.h b/arch/x86/include/uapi/asm/kvm.h
index 5a3022c8af82..0662f644aad9 100644
--- a/arch/x86/include/uapi/asm/kvm.h
+++ b/arch/x86/include/uapi/asm/kvm.h
@@ -437,6 +437,8 @@ struct kvm_vmx_nested_state_hdr {
__u16 flags;
} smm;

+ __u16 pad;
+
__u32 flags;
__u64 preemption_timer_deadline;
};
--
2.30.2