x86/apic/msi: Force reactivation of interrupts at startup time

MSI(X) interrupts need a valid vector configuration early at allocation
time, i.e. before the PCI core enables MSI(X).

With managed interrupts and the new global reservation scheme, the early
configuration will not assign a real device vector, but a special shutdown
vector. When the irq is started up, then the interrupt must be
reconfigured. Tell the MSI irqdomain core about it.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Juergen Gross <jgross@suse.com>
Tested-by: Yu Chen <yu.c.chen@intel.com>
Acked-by: Juergen Gross <jgross@suse.com>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Cc: Alok Kataria <akataria@vmware.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Rui Zhang <rui.zhang@intel.com>
Cc: "K. Y. Srinivasan" <kys@microsoft.com>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Len Brown <lenb@kernel.org>
Link: https://lkml.kernel.org/r/20170913213155.774066582@linutronix.de

arch/x86/kernel/apic/msi.c

@@ -129,7 +129,7 @@ static struct msi_domain_ops pci_msi_domain_ops = {
 
 static struct msi_domain_info pci_msi_domain_info = {
 	.flags		= MSI_FLAG_USE_DEF_DOM_OPS | MSI_FLAG_USE_DEF_CHIP_OPS |
-			  MSI_FLAG_PCI_MSIX,
+			  MSI_FLAG_PCI_MSIX | MSI_FLAG_MUST_REACTIVATE,
 	.ops		= &pci_msi_domain_ops,
 	.chip		= &pci_msi_controller,
 	.handler	= handle_edge_irq,
@@ -167,7 +167,8 @@ static struct irq_chip pci_msi_ir_controller = {
 
 static struct msi_domain_info pci_msi_ir_domain_info = {
 	.flags		= MSI_FLAG_USE_DEF_DOM_OPS | MSI_FLAG_USE_DEF_CHIP_OPS |
-			  MSI_FLAG_MULTI_PCI_MSI | MSI_FLAG_PCI_MSIX,
+			  MSI_FLAG_MULTI_PCI_MSI | MSI_FLAG_PCI_MSIX |
+			  MSI_FLAG_MUST_REACTIVATE,
 	.ops		= &pci_msi_domain_ops,
 	.chip		= &pci_msi_ir_controller,
 	.handler	= handle_edge_irq,