PCI: Check bridge secondary/subordinate bus register

PATCH Applied Yinghai Lu 3 participants 5 messages Sep 11, 2012 – Sep 19, 2012 PCI

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Yinghai Lu

author

2012-09-11 00:19 UTC #0 lore raw

PATCH 1/1 PCI: Check bridge secondary/subordinate bus register

Intel DP43BF requires "pci=assign-busses" to discover some devices.

It turns out BIOS set the bridge 00:1e.0 bus register wrong.

Try to check that wrong range and reject so next pass could only assign bus for that bridge.

	https://bugzilla.kernel.org/show_bug.cgi?id=18412

Reported-by VL <[email protected]>

Tested-by VL <[email protected]>

Signed-off-by Yinghai Lu <[email protected]>

Cc [email protected]

drivers/pci/probe.c +2 -1

index 3cdba8b..a8f1bf6 100644
@@ -729,7 +729,8 @@ int __devinit pci_scan_bridge(struct pci_bus *bus, struct pci_dev *dev, int max,
 
 	/* Check if setup is sensible at all */
 	if (!pass &&
-	    (primary != bus->number || secondary <= bus->number)) {
+	    (primary != bus->number || secondary <= bus->number ||
+	     secondary > subordinate)) {
 		dev_dbg(&dev->dev, "bus configuration invalid, reconfiguring\n");
 		broken = 1;
 	}

Ram Pai

2012-09-11 03:03 UTC #1 lore raw

Quoted 19 lines · Yinghai Lu

Intel DP43BF requires "pci=assign-busses" to discover some devices.
It turns out BIOS set the bridge 00:1e.0 bus register wrong.
Try to check that wrong range and reject so next pass could only assign bus for that bridge.
	https://bugzilla.kernel.org/show_bug.cgi?id=18412
Reported-by VL <[email protected]>
Tested-by VL <[email protected]>
Signed-off-by Yinghai Lu <[email protected]>
Cc [email protected]
drivers/pci/probe.c +0 -0
index 3cdba8b..a8f1bf6 100644

drivers/pci/probe.c int __devinit pci_scan_bridge(struct pci_bus *bus, struct pci_dev *dev, int max, · line 736

Quoted 9 lines

drivers/pci/probe.c +2 -1

@@ -729,7 +729,8 @@ int __devinit pci_scan_bridge(struct pci_bus *bus, struct pci_dev *dev, int max,
 
 	/* Check if setup is sensible at all */
 	if (!pass &&
-	    (primary != bus->number || secondary <= bus->number)) {
+	    (primary != bus->number || secondary <= bus->number ||
+	     secondary > subordinate)) {
 		dev_dbg(&dev->dev, "bus configuration invalid, reconfiguring\n");
 		broken = 1;
 	}

Adding a unlikely() around the condition may help?

Bjorn Helgaas

maintainer Applied

2012-09-18 22:55 UTC #2 lore raw

In reply to Yinghai Lu

Quoted 8 lines · Yinghai Lu

Intel DP43BF requires "pci=assign-busses" to discover some devices.
It turns out BIOS set the bridge 00:1e.0 bus register wrong.
Try to check that wrong range and reject so next pass could only assign bus for that bridge.
        https://bugzilla.kernel.org/show_bug.cgi?id=18412

Applied to pci/yinghai-misc, thanks!

Quoted 19 lines

Reported-by VL <[email protected]>

Tested-by VL <[email protected]>

Signed-off-by Yinghai Lu <[email protected]>

Cc [email protected]

drivers/pci/probe.c +2 -1

index 3cdba8b..a8f1bf6 100644
@@ -729,7 +729,8 @@ int __devinit pci_scan_bridge(struct pci_bus *bus, struct pci_dev *dev, int max,
 
        /* Check if setup is sensible at all */
        if (!pass &&
-           (primary != bus->number || secondary <= bus->number)) {
+           (primary != bus->number || secondary <= bus->number ||
+            secondary > subordinate)) {
                dev_dbg(&dev->dev, "bus configuration invalid, reconfiguring\n");
                broken = 1;
        }

Yinghai Lu

author

2012-09-18 23:55 UTC #3 lore raw

Quoted 11 lines · Bjorn Helgaas

Quoted 8 lines · Yinghai Lu
Intel DP43BF requires "pci=assign-busses" to discover some devices.
It turns out BIOS set the bridge 00:1e.0 bus register wrong.
Try to check that wrong range and reject so next pass could only assign bus for that bridge.
        https://bugzilla.kernel.org/show_bug.cgi?id=18412
Applied to pci/yinghai-misc, thanks!

?
you already put it in pci/yinghai-bridge-subordinate and next

commit 4fe24116ccc5518d5b692cb4354342ee59970ca5
Merge: 8704936 a53d8d3
Author: Bjorn Helgaas <[email protected]>
Date: Tue Sep 18 11:08:09 2012 -0600

Merge branch 'pci/yinghai-bridge-subordinate' into next

* pci/yinghai-bridge-subordinate:
PCI: Check P2P bridge for invalid secondary/subordinate range

commit a53d8d32a2b768cdcdd0703f4754f49b02753d2c

Author: Yinghai Lu <[email protected]>
Date:   Mon Sep 10 17:19:33 2012 -0700

PCI: Check P2P bridge for invalid secondary/subordinate range

Bjorn Helgaas

maintainer

2012-09-19 13:57 UTC #4 lore raw

Quoted 9 lines · Yinghai Lu

Quoted 8 lines · Bjorn Helgaas
Quoted 7 lines · Yinghai Lu
Intel DP43BF requires "pci=assign-busses" to discover some devices.
It turns out BIOS set the bridge 00:1e.0 bus register wrong.
Try to check that wrong range and reject so next pass could only assign bus for that bridge.

Quoted 6 lines

Quoted 3 lines
Quoted 1 line
        https://bugzilla.kernel.org/show_bug.cgi?id=18412
Applied to pci/yinghai-misc, thanks!
?
you already put it in pci/yinghai-bridge-subordinate and next

I did, but I thought it wasn't worth having a separate branch for each of these onesy-twosy patches (this one, vgaarb, kmalloc/kzalloc, bus resource free, etc.), so I decided to consolidate several of them on pci/yinghai-misc and then merge *that* into next.

So pci/yinghai-bridge-subordinate is dead and I dropped it from next (but as I said, it will get to next eventually via pci/yinghai-misc). I don't recommend using my "next" branch as a base. There's usually no need, because patches usually don't depend on other things in "next". If they do, it's simpler to base them on the specific "pci/yinghai-xxx" branch they require.

Quoted 15 lines

commit 4fe24116ccc5518d5b692cb4354342ee59970ca5
Merge: 8704936 a53d8d3
Author: Bjorn Helgaas <[email protected]>
Date: Tue Sep 18 11:08:09 2012 -0600
Merge branch 'pci/yinghai-bridge-subordinate' into next
* pci/yinghai-bridge-subordinate:
PCI: Check P2P bridge for invalid secondary/subordinate range
commit a53d8d32a2b768cdcdd0703f4754f49b02753d2c
Author: Yinghai Lu <[email protected]>
Date:   Mon Sep 10 17:19:33 2012 -0700
PCI: Check P2P bridge for invalid secondary/subordinate range