lkml.org 
[lkml]   [2009]   [Oct]   [10]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
Date
From
Subject[patch 15/28] um: Remove BKL from mmapper
cycle_kernel_lock() was added during the big BKL pushdown. It should
ensure the serializiation against driver init code.

mmapper_open() cannot be called before misc_register() succeeded, but
p_buf might be uninitialized.

Move the initialization of p_buf before the misc_register() call and
get rid of cycle_kernel_lock().

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Jeff Dike <jdike@addtoit.com>
---
arch/um/drivers/mmapper_kern.c | 11 ++++-------
1 file changed, 4 insertions(+), 7 deletions(-)

Index: linux-2.6-tip/arch/um/drivers/mmapper_kern.c
===================================================================
--- linux-2.6-tip.orig/arch/um/drivers/mmapper_kern.c
+++ linux-2.6-tip/arch/um/drivers/mmapper_kern.c
@@ -16,7 +16,7 @@
#include <linux/miscdevice.h>
#include <linux/module.h>
#include <linux/mm.h>
-#include <linux/smp_lock.h>
+
#include <asm/uaccess.h>
#include "mem_user.h"

@@ -78,7 +78,6 @@ out:

static int mmapper_open(struct inode *inode, struct file *file)
{
- cycle_kernel_lock();
return 0;
}

@@ -115,18 +114,16 @@ static int __init mmapper_init(void)
v_buf = (char *) find_iomem("mmapper", &mmapper_size);
if (mmapper_size == 0) {
printk(KERN_ERR "mmapper_init - find_iomem failed\n");
- goto out;
+ return -ENODEV;
}
+ p_buf = __pa(v_buf);

err = misc_register(&mmapper_dev);
if (err) {
printk(KERN_ERR "mmapper - misc_register failed, err = %d\n",
err);
- goto out;
+ return err;;
}
-
- p_buf = __pa(v_buf);
-out:
return 0;
}




\
 
 \ /
  Last update: 2009-10-10 18:15    [W:0.464 / U:0.340 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site