From: Zijun Hu <zijun.hu@oss.qualcomm.com>
misc_open() may request module for miscdevice with dynamic minor
which is meaningless since macro MODULE_ALIAS_MISCDEV() is not
applicable for dynamic minor.
Fix by only requesting module for miscdevice with fixed minor.
Signed-off-by: Zijun Hu <zijun.hu@oss.qualcomm.com>
---
drivers/char/misc.c | 8 +++++---
1 file changed, 5 insertions(+), 3 deletions(-)
diff --git a/drivers/char/misc.c b/drivers/char/misc.c
index 96ed343cf5c8509a09855020049a9af82a3ede95..a0aae0fc792666a7bdc0ba00da9dc02ff9cead42 100644
--- a/drivers/char/misc.c
+++ b/drivers/char/misc.c
@@ -132,7 +132,8 @@ static int misc_open(struct inode *inode, struct file *file)
break;
}
- if (!new_fops) {
+ /* Only request module for fixed minor code */
+ if (!new_fops && minor < MISC_DYNAMIC_MINOR) {
mutex_unlock(&misc_mtx);
request_module("char-major-%d-%d", MISC_MAJOR, minor);
mutex_lock(&misc_mtx);
@@ -144,10 +145,11 @@ static int misc_open(struct inode *inode, struct file *file)
new_fops = fops_get(iter->fops);
break;
}
- if (!new_fops)
- goto fail;
}
+ if (!new_fops)
+ goto fail;
+
/*
* Place the miscdevice in the file's
* private_data so it can be used by the
--
2.34.1