[PATCH] PCIE: check and return bus_register errors

["Randy.Dunlap" <rdunlap@xenotime.net>]

On Fri, 7 Jul 2006 17:10:15 -0700 Andrew Morton wrote:

> "Randy.Dunlap" <rdunlap@xenotime.net> wrote:
> >
> > +			if (!pcie_dev_registered)
> > +				pcie_port_bus_register();
> > +
> 
> Wonderful.  You're forced to drop all error checking on the floor because
> pcie_port_bus_register() assumes that nobody could possibly ever be
> interested in actually checking for errors.
> 
> What happens if the bus_register() fails and the driver cheerily blunders
> along assuming that pcie_port_bus_type is registered?  Incomprehensible lkml
> oops reports, I'm suspecting..
> 
> Let's start stamping this out.  Could I please ask that you first prepare a
> patch which fixes pcie_port_bus_register() (and mark it __must_check) and
> then let's actually, like, check for errors?



From: Randy Dunlap <rdunlap@xenotime.net>

Have pcie_port_bus_register() notice and return errors.
Mark it __must_check so that its caller(s) must check its return value.

Signed-off-by: Randy Dunlap <rdunlap@xenotime.net>
---
 drivers/pci/pcie/portdrv.h      |    2 +-
 drivers/pci/pcie/portdrv_core.c |    5 +++--
 drivers/pci/pcie/portdrv_pci.c  |    9 +++++++--
 3 files changed, 11 insertions(+), 5 deletions(-)

--- linux-2618-rc1.orig/drivers/pci/pcie/portdrv_core.c
+++ linux-2618-rc1/drivers/pci/pcie/portdrv_core.c
@@ -6,6 +6,7 @@
  * Copyright (C) Tom Long Nguyen (tom.l.nguyen@intel.com)
  */
 
+#include <linux/compiler.h>
 #include <linux/module.h>
 #include <linux/pci.h>
 #include <linux/kernel.h>
@@ -402,9 +403,9 @@ void pcie_port_device_remove(struct pci_
 		pci_disable_msi(dev);
 }
 
-void pcie_port_bus_register(void)
+int __must_check pcie_port_bus_register(void)
 {
-	bus_register(&pcie_port_bus_type);
+	return bus_register(&pcie_port_bus_type);
 }
 
 void pcie_port_bus_unregister(void)
--- linux-2618-rc1.orig/drivers/pci/pcie/portdrv_pci.c
+++ linux-2618-rc1/drivers/pci/pcie/portdrv_pci.c
@@ -127,12 +127,17 @@ static struct pci_driver pcie_portdrv = 
 
 static int __init pcie_portdrv_init(void)
 {
-	int retval = 0;
+	int retval;
 
-	pcie_port_bus_register();
+	retval = pcie_port_bus_register();
+	if (retval) {
+		printk(KERN_WARNING "PCIE: bus_register error: %d\n", retval);
+		goto out;
+	}
 	retval = pci_register_driver(&pcie_portdrv);
 	if (retval)
 		pcie_port_bus_unregister();
+ out:
 	return retval;
 }
 
--- linux-2618-rc1.orig/drivers/pci/pcie/portdrv.h
+++ linux-2618-rc1/drivers/pci/pcie/portdrv.h
@@ -39,7 +39,7 @@ extern int pcie_port_device_suspend(stru
 extern int pcie_port_device_resume(struct pci_dev *dev);
 #endif
 extern void pcie_port_device_remove(struct pci_dev *dev);
-extern void pcie_port_bus_register(void);
+extern int pcie_port_bus_register(void);
 extern void pcie_port_bus_unregister(void);
 
 #endif /* _PORTDRV_H_ */



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