[PATCH 4.4 131/137] Revert "x86/PCI: Dont alloc pcibios-irq when MSI is enabled"

[Greg Kroah-Hartman]

4.4-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Bjorn Helgaas <bhelgaas@xxxxxxxxxx>

commit fe25d078874f2c29c38f4160467d74f5756537c9 upstream.

Revert 8affb487d4a4 ("x86/PCI: Don't alloc pcibios-irq when MSI is
enabled").

This is part of reverting 991de2e59090 ("PCI, x86: Implement
pcibios_alloc_irq() and pcibios_free_irq()") to fix regressions it
introduced.

Link: https://bugzilla.kernel.org/show_bug.cgi?id=111211
Fixes: 991de2e59090 ("PCI, x86: Implement pcibios_alloc_irq() and pcibios_free_irq()")
Signed-off-by: Bjorn Helgaas <bhelgaas@xxxxxxxxxx>
Acked-by: Rafael J. Wysocki <rafael@xxxxxxxxxx>
CC: Jiang Liu <jiang.liu@xxxxxxxxxxxxxxx>
CC: Joerg Roedel <jroedel@xxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
 arch/x86/pci/common.c |    8 --------
 1 file changed, 8 deletions(-)

--- a/arch/x86/pci/common.c
+++ b/arch/x86/pci/common.c
@@ -675,14 +675,6 @@ int pcibios_add_device(struct pci_dev *d
 
 int pcibios_alloc_irq(struct pci_dev *dev)
 {
-	/*
-	 * If the PCI device was already claimed by core code and has
-	 * MSI enabled, probing of the pcibios IRQ will overwrite
-	 * dev->irq.  So bail out if MSI is already enabled.
-	 */
-	if (pci_dev_msi_enabled(dev))
-		return -EBUSY;
-
 	return pcibios_enable_irq(dev);
 }