x86: adds paravirt hook for swapgs

This patch adds paravirt hook for swapgs operation, which is a privileged
operation in x86_64.

Signed-off-by: Glauber de Oliveira Costa <gcosta@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
diff --git a/arch/x86/kernel/paravirt.c b/arch/x86/kernel/paravirt.c
index 072c1a0..e7c17cc 100644
--- a/arch/x86/kernel/paravirt.c
+++ b/arch/x86/kernel/paravirt.c
@@ -390,6 +390,7 @@
 
 	.irq_enable_syscall_ret = native_irq_enable_syscall_ret,
 	.iret = native_iret,
+	.swapgs = native_swapgs,
 
 	.set_iopl_mask = native_set_iopl_mask,
 	.io_delay = native_io_delay,