From: Marcel Holtmann <marcel@xxxxxxxxxxxx> commit 8670b2b8b029a6650d133486be9d2ace146fd29a upstream. udev has a feature of creating /dev/<node> device-nodes if it finds a devnode:<node> modalias. This allows for auto-loading of modules that provide the node. This requires to use a statically allocated minor number for misc character devices. However, rfkill uses dynamic minor numbers and prevents auto-loading of the module. So allocate the next static misc minor number and use it for rfkill. Signed-off-by: Marcel Holtmann <marcel@xxxxxxxxxxxx> Link: https://lore.kernel.org/r/20191024174042.19851-1-marcel@xxxxxxxxxxxx Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- include/linux/miscdevice.h | 1 + net/rfkill/core.c | 9 +++++++-- 2 files changed, 8 insertions(+), 2 deletions(-) --- a/include/linux/miscdevice.h +++ b/include/linux/miscdevice.h @@ -57,6 +57,7 @@ #define UHID_MINOR 239 #define USERIO_MINOR 240 #define VHOST_VSOCK_MINOR 241 +#define RFKILL_MINOR 242 #define MISC_DYNAMIC_MINOR 255 struct device; --- a/net/rfkill/core.c +++ b/net/rfkill/core.c @@ -1316,10 +1316,12 @@ static const struct file_operations rfki .llseek = no_llseek, }; +#define RFKILL_NAME "rfkill" + static struct miscdevice rfkill_miscdev = { - .name = "rfkill", .fops = &rfkill_fops, - .minor = MISC_DYNAMIC_MINOR, + .name = RFKILL_NAME, + .minor = RFKILL_MINOR, }; static int __init rfkill_init(void) @@ -1371,3 +1373,6 @@ static void __exit rfkill_exit(void) class_unregister(&rfkill_class); } module_exit(rfkill_exit); + +MODULE_ALIAS_MISCDEV(RFKILL_MINOR); +MODULE_ALIAS("devname:" RFKILL_NAME);
