From e3c699b38ef3c59521fdd1732efcaaa789d81440 Mon Sep 17 00:00:00 2001 From: Stefan Weinhuber Date: Mon, 5 Feb 2007 21:17:04 +0100 Subject: [PATCH] [S390] dasd: fix bug in dasd initialization cleanup The initialization of the dasd_eer code is one of the last steps of the dasd driver initialization. When initialization fails in one of the earlier steps, the dasd_exit function is called to clean up what has been done so far. So the dasd_eer_exit function may be called, although the dasd_eer_init function wasn't called before and dasd_eer_exit tries to unregister a misc device that wasn't registered, which results in a BUG. Make sure that dasd_eer_exit can be called without initialization. Use a dynamically allocated struct miscdevice instead of a static one, so we only try to unregister the device if it exists and was actually registered. Signed-off-by: Stefan Weinhuber Signed-off-by: Martin Schwidefsky --- drivers/s390/block/dasd_eer.c | 24 +++++++++++++++++------- 1 file changed, 17 insertions(+), 7 deletions(-) diff --git a/drivers/s390/block/dasd_eer.c b/drivers/s390/block/dasd_eer.c index e0bf30ebb215..6cedc914077e 100644 --- a/drivers/s390/block/dasd_eer.c +++ b/drivers/s390/block/dasd_eer.c @@ -658,18 +658,24 @@ static struct file_operations dasd_eer_fops = { .owner = THIS_MODULE, }; -static struct miscdevice dasd_eer_dev = { - .minor = MISC_DYNAMIC_MINOR, - .name = "dasd_eer", - .fops = &dasd_eer_fops, -}; +static struct miscdevice *dasd_eer_dev = NULL; int __init dasd_eer_init(void) { int rc; - rc = misc_register(&dasd_eer_dev); + dasd_eer_dev = kzalloc(sizeof(*dasd_eer_dev), GFP_KERNEL); + if (!dasd_eer_dev) + return -ENOMEM; + + dasd_eer_dev->minor = MISC_DYNAMIC_MINOR; + dasd_eer_dev->name = "dasd_eer"; + dasd_eer_dev->fops = &dasd_eer_fops; + + rc = misc_register(dasd_eer_dev); if (rc) { + kfree(dasd_eer_dev); + dasd_eer_dev = NULL; MESSAGE(KERN_ERR, "%s", "dasd_eer_init could not " "register misc device"); return rc; @@ -680,5 +686,9 @@ int __init dasd_eer_init(void) void dasd_eer_exit(void) { - WARN_ON(misc_deregister(&dasd_eer_dev) != 0); + if (dasd_eer_dev) { + WARN_ON(misc_deregister(dasd_eer_dev) != 0); + kfree(dasd_eer_dev); + dasd_eer_dev = NULL; + } } -- 2.20.1