Commit 497f16f2 authored Dec 17, 2011 by Yinghai Lu Committed by Linus Torvalds Dec 18, 2011

pci: Fix hotplug of Express Module with pci bridges

I noticed that hotplug of one setup does not work with recent change in
pci tree.

After checking the bridge conf setup, I noticed that the bridges get
assigned but do not get enabled.

The reason is the following commit, while simply ignores bridge
resources when enabling a pci device:

| commit bbef98ab
| Author: Ram Pai <linuxram@us.ibm.com>
| Date:   Sun Nov 6 10:33:10 2011 +0800
|
|    PCI: defer enablement of SRIOV BARS
|...
|    NOTE: Note, there is subtle change in the pci_enable_device() API.  Any
|    driver that depends on SRIOV BARS to be enabled in pci_enable_device()
|    can fail.

Put back bridge resource and ROM resource checking to fix the problem.

That should fix regression like BIOS does not assign correct resource to
bridge.

Discussion can be found at:
	http://www.spinics.net/lists/linux-pci/msg12874.html



Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Acked-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

parent ab347d94

drivers/pci/pci.c

+5 −1

Original line number	Diff line number	Diff line
		@@ -1129,7 +1129,11 @@ static int __pci_enable_device_flags(struct pci_dev *dev,
		if (atomic_add_return(1, &dev->enable_cnt) > 1)
		return 0; /* already enabled */

		for (i = 0; i < PCI_ROM_RESOURCE; i++)
		/* only skip sriov related */
		for (i = 0; i <= PCI_ROM_RESOURCE; i++)
		if (dev->resource[i].flags & flags)
		bars \|= (1 << i);
		for (i = PCI_BRIDGE_RESOURCES; i < DEVICE_COUNT_RESOURCE; i++)
		if (dev->resource[i].flags & flags)
		bars \|= (1 << i);

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