[patch V3 52/60] x86/xen/apic: Use standard apic driver mechanism for Xen PV

[Thomas Gleixner]

Instead of setting the Xen PV apic driver very early during boot, just use
the standard apic driver probing by setting an appropriate
x86_init.irqs.intr_mode_init callback.

At the same time eliminate xen_apic_check() which has never been used.

The #ifdef CONFIG_X86_LOCAL_APIC around the call of xen_init_apic()
can be removed, too, as CONFIG_XEN depends on CONFIG_X86_LOCAL_APIC.

Signed-off-by: Juergen Gross <jgross@xxxxxxxx>
Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Link: https://lore.kernel.org/lkml/aa086365-fd02-210f-67c6-5c9175c0dfee@xxxxxxxx
---
V3: New patch to address the XenPV fallout
---
 arch/x86/xen/apic.c         |   11 -----------
 arch/x86/xen/enlighten_pv.c |    4 +---
 2 files changed, 1 insertion(+), 14 deletions(-)

--- a/arch/x86/xen/apic.c
+++ b/arch/x86/xen/apic.c
@@ -158,19 +158,8 @@ static struct apic xen_pv_apic = {
 	.icr_write 			= xen_apic_icr_write,
 };
 
-static void __init xen_apic_check(void)
-{
-	apic_install_driver(&xen_pv_apic);
-}
-
 void __init xen_init_apic(void)
 {
 	x86_apic_ops.io_apic_read = xen_io_apic_read;
-	/* On PV guests the APIC CPUID bit is disabled so none of the
-	 * routines end up executing. */
-	if (!xen_initial_domain())
-		apic_install_driver(&xen_pv_apic);
-
-	x86_platform.apic_post_init = xen_apic_check;
 }
 apic_driver(xen_pv_apic);
--- a/arch/x86/xen/enlighten_pv.c
+++ b/arch/x86/xen/enlighten_pv.c
@@ -1326,7 +1326,7 @@ asmlinkage __visible void __init xen_sta
 
 	x86_init.resources.memory_setup = xen_memory_setup;
 	x86_init.irqs.intr_mode_select	= x86_init_noop;
-	x86_init.irqs.intr_mode_init	= x86_init_noop;
+	x86_init.irqs.intr_mode_init	= x86_64_probe_apic;
 	x86_init.oem.arch_setup = xen_arch_setup;
 	x86_init.oem.banner = xen_banner;
 	x86_init.hyper.init_platform = xen_pv_init_platform;
@@ -1366,12 +1366,10 @@ asmlinkage __visible void __init xen_sta
 
 	xen_init_capabilities();
 
-#ifdef CONFIG_X86_LOCAL_APIC
 	/*
 	 * set up the basic apic ops.
 	 */
 	xen_init_apic();
-#endif
 
 	machine_ops = xen_machine_ops;