Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 815d2d50 authored by Andrew Morton's avatar Andrew Morton Committed by Greg Kroah-Hartman
Browse files

driver core: debug for bad dev_attr_show() return value. 

Try to find the culprit who caused
http://bugzilla.kernel.org/show_bug.cgi?id=10150



Cc: <balajirrao@gmail.com>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@suse.de>
parent c9698d6b

drivers/base/core.c

+5 −0
Original line number Diff line number Diff line
@@ -19,6 +19,7 @@ 
#include <linux/kdev_t.h>

#include <linux/notifier.h>

#include <linux/genhd.h>

#include <linux/kallsyms.h>

#include <asm/semaphore.h>



#include "base.h"
@@ -68,6 +69,10 @@ static ssize_t dev_attr_show(struct kobject *kobj, struct attribute *attr, 


	if (dev_attr->show)

		ret = dev_attr->show(dev, dev_attr, buf);

	if (ret >= (ssize_t)PAGE_SIZE) {

		print_symbol("dev_attr_show: %s returned bad count\n",

				(unsigned long)dev_attr->show);

	}

	return ret;

}

fs/sysfs/file.c

+7 −1
Original line number Diff line number Diff line
@@ -12,6 +12,7 @@ 


#include <linux/module.h>

#include <linux/kobject.h>

#include <linux/kallsyms.h>

#include <linux/namei.h>

#include <linux/poll.h>

#include <linux/list.h>
@@ -86,7 +87,12 @@ static int fill_read_buffer(struct dentry * dentry, struct sysfs_buffer * buffer 
	 * The code works fine with PAGE_SIZE return but it's likely to

	 * indicate truncated result or overflow in normal use cases.

	 */

	BUG_ON(count >= (ssize_t)PAGE_SIZE);

	if (count >= (ssize_t)PAGE_SIZE) {

		print_symbol("fill_read_buffer: %s returned bad count\n",

			(unsigned long)ops->show);

		/* Try to struggle along */

		count = PAGE_SIZE - 1;

	}

	if (count >= 0) {

		buffer->needs_read_fill = 0;

		buffer->count = count;