Commit 066d79e4 authored Dec 02, 2014 by Boris Ostrovsky Committed by David Vrabel Dec 04, 2014

xen/pci: Defer initialization of MSI ops on HVM guests



If the hardware supports APIC virtualization we may decide not to use
pirqs and instead use APIC/x2APIC directly, meaning that we don't want
to set x86_msi.setup_msi_irqs and x86_msi.teardown_msi_irq to
Xen-specific routines.  However, x2APIC is not set up by the time
pci_xen_hvm_init() is called so we need to postpone setting these ops
until later, when we know which APIC mode is used.

(Note that currently x2APIC is never initialized on HVM guests. This
may change in the future)

Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Acked-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: David Vrabel <david.vrabel@citrix.com>

parent 6945c59c

arch/x86/pci/xen.c

+13 −2

Original line number	Diff line number	Diff line
		@@ -431,6 +431,14 @@ int __init pci_xen_init(void)
		return 0;
		}

		#ifdef CONFIG_PCI_MSI
		void __init xen_msi_init(void)
		{
		x86_msi.setup_msi_irqs = xen_hvm_setup_msi_irqs;
		x86_msi.teardown_msi_irq = xen_teardown_msi_irq;
		}
		#endif

		int __init pci_xen_hvm_init(void)
		{
		if (!xen_have_vector_callback \|\| !xen_feature(XENFEAT_hvm_pirqs))
		@@ -445,8 +453,11 @@ int __init pci_xen_hvm_init(void)
		#endif

		#ifdef CONFIG_PCI_MSI
		x86_msi.setup_msi_irqs = xen_hvm_setup_msi_irqs;
		x86_msi.teardown_msi_irq = xen_teardown_msi_irq;
		/*
		* We need to wait until after x2apic is initialized
		* before we can set MSI IRQ ops.
		*/
		x86_platform.apic_post_init = xen_msi_init;
		#endif
		return 0;
		}

Admin message