Merge tag 'pci-v3.13-fixes-2' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci

Pull PCI updates from Bjorn Helgaas:
 "PCI device hotplug
    - Move device_del() from pci_stop_dev() to pci_destroy_dev() (Rafael
      Wysocki)

  Host bridge drivers
    - Update maintainers for DesignWare, i.MX6, Armada, R-Car (Bjorn
      Helgaas)
    - mvebu: Return 'unsupported' for Interrupt Line and Interrupt Pin
      (Jason Gunthorpe)

  Miscellaneous
    - Avoid unnecessary CPU switch when calling .probe() (Alexander
      Duyck)
    - Revert "workqueue: allow work_on_cpu() to be called recursively"
      (Bjorn Helgaas)
    - Disable Bus Master only on kexec reboot (Khalid Aziz)
    - Omit PCI ID macro strings to shorten quirk names for LTO (Michal
      Marek)"

* tag 'pci-v3.13-fixes-2' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci:
  MAINTAINERS: Add DesignWare, i.MX6, Armada, R-Car PCI host maintainers
  PCI: Disable Bus Master only on kexec reboot
  PCI: mvebu: Return 'unsupported' for Interrupt Line and Interrupt Pin
  PCI: Omit PCI ID macro strings to shorten quirk names
  PCI: Move device_del() from pci_stop_dev() to pci_destroy_dev()
  Revert "workqueue: allow work_on_cpu() to be called recursively"
  PCI: Avoid unnecessary CPU switch when calling driver .probe() method

3 files changed, 38 insertions, 9 deletions

diff --git a/drivers/pci/host/pci-mvebu.c b/drivers/pci/host/pci-mvebu.c
index c269e430c760..2aa7b77c7c88 100644
--- a/drivers/pci/host/pci-mvebu.c
+++ b/drivers/pci/host/pci-mvebu.c
@@ -447,6 +447,11 @@ static int mvebu_sw_pci_bridge_read(struct mvebu_pcie_port *port,
 		*value = 0;
 		break;
 
+	case PCI_INTERRUPT_LINE:
+		/* LINE PIN MIN_GNT MAX_LAT */
+		*value = 0;
+		break;
+
 	default:
 		*value = 0xffffffff;
 		return PCIBIOS_BAD_REGISTER_NUMBER;
diff --git a/drivers/pci/pci-driver.c b/drivers/pci/pci-driver.c
index 9042fdbd7244..25f0bc659164 100644
--- a/drivers/pci/pci-driver.c
+++ b/drivers/pci/pci-driver.c
@@ -19,6 +19,7 @@
 #include <linux/cpu.h>
 #include <linux/pm_runtime.h>
 #include <linux/suspend.h>
+#include <linux/kexec.h>
 #include "pci.h"
 
 struct pci_dynid {
@@ -288,12 +289,27 @@ static int pci_call_probe(struct pci_driver *drv, struct pci_dev *dev,
 	int error, node;
 	struct drv_dev_and_id ddi = { drv, dev, id };
 
-	/* Execute driver initialization on node where the device's
-	   bus is attached to.  This way the driver likely allocates
-	   its local memory on the right node without any need to
-	   change it. */
+	/*
+	 * Execute driver initialization on node where the device is
+	 * attached.  This way the driver likely allocates its local memory
+	 * on the right node.
+	 */
 	node = dev_to_node(&dev->dev);
-	if (node >= 0) {
+
+	/*
+	 * On NUMA systems, we are likely to call a PF probe function using
+	 * work_on_cpu().  If that probe calls pci_enable_sriov() (which
+	 * adds the VF devices via pci_bus_add_device()), we may re-enter
+	 * this function to call the VF probe function.  Calling
+	 * work_on_cpu() again will cause a lockdep warning.  Since VFs are
+	 * always on the same node as the PF, we can work around this by
+	 * avoiding work_on_cpu() when we're already on the correct node.
+	 *
+	 * Preemption is enabled, so it's theoretically unsafe to use
+	 * numa_node_id(), but even if we run the probe function on the
+	 * wrong node, it should be functionally correct.
+	 */
+	if (node >= 0 && node != numa_node_id()) {
 		int cpu;
 
 		get_online_cpus();
@@ -305,6 +321,7 @@ static int pci_call_probe(struct pci_driver *drv, struct pci_dev *dev,
 		put_online_cpus();
 	} else
 		error = local_pci_probe(&ddi);
+
 	return error;
 }
 
@@ -399,12 +416,17 @@ static void pci_device_shutdown(struct device *dev)
 	pci_msi_shutdown(pci_dev);
 	pci_msix_shutdown(pci_dev);
 
+#ifdef CONFIG_KEXEC
 	/*
-	 * Turn off Bus Master bit on the device to tell it to not
-	 * continue to do DMA. Don't touch devices in D3cold or unknown states.
+	 * If this is a kexec reboot, turn off Bus Master bit on the
+	 * device to tell it to not continue to do DMA. Don't touch
+	 * devices in D3cold or unknown states.
+	 * If it is not a kexec reboot, firmware will hit the PCI
+	 * devices with big hammer and stop their DMA any way.
 	 */
-	if (pci_dev->current_state <= PCI_D3hot)
+	if (kexec_in_progress && (pci_dev->current_state <= PCI_D3hot))
 		pci_clear_master(pci_dev);
+#endif
 }
 
 #ifdef CONFIG_PM
diff --git a/drivers/pci/remove.c b/drivers/pci/remove.c
index 1576851028db..cc9337a71529 100644
--- a/drivers/pci/remove.c
+++ b/drivers/pci/remove.c
@@ -24,7 +24,7 @@ static void pci_stop_dev(struct pci_dev *dev)
 	if (dev->is_added) {
 		pci_proc_detach_device(dev);
 		pci_remove_sysfs_dev_files(dev);
-		device_del(&dev->dev);
+		device_release_driver(&dev->dev);
 		dev->is_added = 0;
 	}
 
@@ -34,6 +34,8 @@ static void pci_stop_dev(struct pci_dev *dev)
 
 static void pci_destroy_dev(struct pci_dev *dev)
 {
+	device_del(&dev->dev);
+
 	down_write(&pci_bus_sem);
 	list_del(&dev->bus_list);
 	up_write(&pci_bus_sem);