x86/virt, x86/platform: Add ->guest_late_init() callback to hypervisor_x86 structure

Add a new guest_late_init callback to the hypervisor_x86 structure. It
will replace the current kvm_guest_init() call which is changed to
make use of the new callback.

Signed-off-by: Juergen Gross <jgross@suse.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: kvm@vger.kernel.org
Cc: rkrcmar@redhat.com
Link: http://lkml.kernel.org/r/20171109132739.23465-5-jgross@suse.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>

arch/x86/include/asm/kvm_para.h

@@ -88,7 +88,6 @@ static inline long kvm_hypercall4(unsigned int nr, unsigned long p1,
 #ifdef CONFIG_KVM_GUEST
 bool kvm_para_available(void);
 unsigned int kvm_arch_para_features(void);
-void __init kvm_guest_init(void);
 void kvm_async_pf_task_wait(u32 token, int interrupt_kernel);
 void kvm_async_pf_task_wake(u32 token);
 u32 kvm_read_and_reset_pf_reason(void);
@@ -103,7 +102,6 @@ static inline void kvm_spinlock_init(void)
 #endif /* CONFIG_PARAVIRT_SPINLOCKS */
 
 #else /* CONFIG_KVM_GUEST */
-#define kvm_guest_init() do {} while (0)
 #define kvm_async_pf_task_wait(T, I) do {} while(0)
 #define kvm_async_pf_task_wake(T) do {} while(0)
 

arch/x86/include/asm/x86_init.h

@@ -117,11 +117,13 @@ struct x86_init_pci {
 /**
  * struct x86_hyper_init - x86 hypervisor init functions
  * @init_platform:		platform setup
+ * @guest_late_init:		guest late init
  * @x2apic_available:		X2APIC detection
  * @init_mem_mapping:		setup early mappings during init_mem_mapping()
  */
 struct x86_hyper_init {
 	void (*init_platform)(void);
+	void (*guest_late_init)(void);
 	bool (*x2apic_available)(void);
 	void (*init_mem_mapping)(void);
 };

arch/x86/kernel/kvm.c

@@ -465,7 +465,7 @@ static void __init kvm_apf_trap_init(void)
 	update_intr_gate(X86_TRAP_PF, async_page_fault);
 }
 
-void __init kvm_guest_init(void)
+static void __init kvm_guest_init(void)
 {
 	int i;
 
@@ -548,6 +548,7 @@ const __initconst struct hypervisor_x86 x86_hyper_kvm = {
 	.name			= "KVM",
 	.detect			= kvm_detect,
 	.type			= X86_HYPER_KVM,
+	.init.guest_late_init	= kvm_guest_init,
 	.init.x2apic_available	= kvm_para_available,
 };
 

arch/x86/kernel/setup.c

@@ -1294,7 +1294,7 @@ void __init setup_arch(char **cmdline_p)
 
 	io_apic_init_mappings();
 
-	kvm_guest_init();
+	x86_init.hyper.guest_late_init();
 
 	e820__reserve_resources();
 	e820__register_nosave_regions(max_low_pfn);

arch/x86/kernel/x86_init.c

@@ -86,6 +86,7 @@ struct x86_init_ops x86_init __initdata = {
 
 	.hyper = {
 		.init_platform		= x86_init_noop,
+		.guest_late_init	= x86_init_noop,
 		.x2apic_available	= bool_x86_init_noop,
 		.init_mem_mapping	= x86_init_noop,
 	},