[PATCH] ipmi: Make sure drivers were registered before unregistering them

From: Matthew Garrett
Date: Thu Jun 10 2010 - 13:53:42 EST


The ipmi code will never register a PCI or Open Firmware driver if
a hardcoded device is provided by the user. This can cause us to attempt
to unregister a driver that was never registered, resulting in an oops.
Keep track of registration in order to avoid this.

Signed-off-by: Matthew Garrett <mjg@xxxxxxxxxx>
---
drivers/char/ipmi/ipmi_si_intf.c | 21 +++++++++++++++++----
1 files changed, 17 insertions(+), 4 deletions(-)

diff --git a/drivers/char/ipmi/ipmi_si_intf.c b/drivers/char/ipmi/ipmi_si_intf.c
index 35603dd..311f85b 100644
--- a/drivers/char/ipmi/ipmi_si_intf.c
+++ b/drivers/char/ipmi/ipmi_si_intf.c
@@ -302,6 +302,12 @@ struct smi_info {

static int force_kipmid[SI_MAX_PARMS];
static int num_force_kipmid;
+#ifdef CONFIG_PCI
+static int pci_registered;
+#endif
+#ifdef CONFIG_PPC_OF
+static int of_registered;
+#endif

static unsigned int kipmid_max_busy_us[SI_MAX_PARMS];
static int num_max_busy_us;
@@ -3314,6 +3320,8 @@ static __devinit int init_ipmi_si(void)
rv = pci_register_driver(&ipmi_pci_driver);
if (rv)
printk(KERN_ERR PFX "Unable to register PCI driver: %d\n", rv);
+ else
+ pci_registered = 1;
#endif

#ifdef CONFIG_ACPI
@@ -3330,6 +3338,7 @@ static __devinit int init_ipmi_si(void)

#ifdef CONFIG_PPC_OF
of_register_platform_driver(&ipmi_of_platform_driver);
+ of_registered = 1;
#endif

/* We prefer devices with interrupts, but in the case of a machine
@@ -3383,11 +3392,13 @@ static __devinit int init_ipmi_si(void)
if (unload_when_empty && list_empty(&smi_infos)) {
mutex_unlock(&smi_infos_lock);
#ifdef CONFIG_PCI
- pci_unregister_driver(&ipmi_pci_driver);
+ if (pci_registered)
+ pci_unregister_driver(&ipmi_pci_driver);
#endif

#ifdef CONFIG_PPC_OF
- of_unregister_platform_driver(&ipmi_of_platform_driver);
+ if (of_registered)
+ of_unregister_platform_driver(&ipmi_of_platform_driver);
#endif
driver_unregister(&ipmi_driver.driver);
printk(KERN_WARNING PFX
@@ -3478,14 +3489,16 @@ static __exit void cleanup_ipmi_si(void)
return;

#ifdef CONFIG_PCI
- pci_unregister_driver(&ipmi_pci_driver);
+ if (pci_registered)
+ pci_unregister_driver(&ipmi_pci_driver);
#endif
#ifdef CONFIG_ACPI
pnp_unregister_driver(&ipmi_pnp_driver);
#endif

#ifdef CONFIG_PPC_OF
- of_unregister_platform_driver(&ipmi_of_platform_driver);
+ if (of_registered)
+ of_unregister_platform_driver(&ipmi_of_platform_driver);
#endif

mutex_lock(&smi_infos_lock);
--
1.7.0.1

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