x86/irq/32: Invoke irq_ctx_init() from init_IRQ()

irq_ctx_init() is invoked from native_init_IRQ() or from xen_init_IRQ()
code. There is no reason to have this split. The interrupt stacks must be
allocated no matter what.

Invoke it from init_IRQ() before invoking the native or XEN init
implementation.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Juergen Gross <jgross@suse.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Josh Abraham <j.abraham1776@gmail.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Mike Rapoport <rppt@linux.vnet.ibm.com>
Cc: Nicolai Stange <nstange@suse.de>
Cc: Sean Christopherson <sean.j.christopherson@intel.com>
Cc: Stefano Stabellini <sstabellini@kernel.org>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: x86-ml <x86@kernel.org>
Cc: xen-devel@lists.xenproject.org
Link: https://lkml.kernel.org/r/20190414160146.001162606@linutronix.de

arch/x86/kernel/irqinit.c

@@ -91,6 +91,8 @@ void __init init_IRQ(void)
 	for (i = 0; i < nr_legacy_irqs(); i++)
 		per_cpu(vector_irq, 0)[ISA_IRQ_VECTOR(i)] = irq_to_desc(i);
 
+	irq_ctx_init(smp_processor_id());
+
 	x86_init.irqs.intr_init();
 }
 
@@ -104,6 +106,4 @@ void __init native_init_IRQ(void)
 
 	if (!acpi_ioapic && !of_ioapic && nr_legacy_irqs())
 		setup_irq(2, &irq2);
-
-	irq_ctx_init(smp_processor_id());
 }

drivers/xen/events/events_base.c

@@ -1687,7 +1687,6 @@ void __init xen_init_IRQ(void)
 
 #ifdef CONFIG_X86
 	if (xen_pv_domain()) {
-		irq_ctx_init(smp_processor_id());
 		if (xen_initial_domain())
 			pci_xen_initial_domain();
 	}