[PATCH 3/3] char: misc: Fix improper and inaccurate error code returned by misc_init()

From: Zijun Hu
Date: Fri Jun 20 2025 - 10:41:45 EST


From: Zijun Hu <zijun.hu@xxxxxxxxxxxxxxxx>

misc_init() returns -EIO for __register_chrdev() invocation failure, but:

- -EIO is for I/O error normally, but __register_chrdev() does not do I/O.
- -EIO can not cover various error codes returned by __register_chrdev().

Fix by returning error code of __register_chrdev().

Signed-off-by: Zijun Hu <zijun.hu@xxxxxxxxxxxxxxxx>
---
drivers/char/misc.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/char/misc.c b/drivers/char/misc.c
index f5ef8c175adb559e67dfe905d43d1404b249cc9e..e5ea36bbf6b3d1313eb35d3259617bf90c55727d 100644
--- a/drivers/char/misc.c
+++ b/drivers/char/misc.c
@@ -296,8 +296,8 @@ static int __init misc_init(void)
if (err)
goto fail_remove;

- err = -EIO;
- if (__register_chrdev(MISC_MAJOR, 0, MINORMASK + 1, "misc", &misc_fops))
+ err = __register_chrdev(MISC_MAJOR, 0, MINORMASK + 1, "misc", &misc_fops);
+ if (err < 0)
goto fail_printk;
return 0;


--
2.34.1