Re: [lkp] [gpio] 3c702e9987: kmsg.user_verbs:couldn't_register_device_number

From: Linus Walleij
Date: Sun Feb 14 2016 - 12:49:00 EST


On Sun, Feb 14, 2016 at 9:06 AM, Michael Welling <mwelling@xxxxxxxx> wrote:

> enum {
> IB_UVERBS_MAJOR = 231,
> IB_UVERBS_BASE_MINOR = 192,
> IB_UVERBS_MAX_DEVICES = 32
> };
>
> #define IB_UVERBS_BASE_DEV MKDEV(IB_UVERBS_MAJOR, IB_UVERBS_BASE_MINOR)
>
> Something tells me that a new GPIO chardev is taking this spot.

I don't think so, since gpio is reserving it as a core_initcall() it
gets a high chardev major. It's likely the device that used to
be device 232 stealing the fingerprint sensor slot that got
pushed down and is now stealing device 231 infiniband.

Maybe I should make a patch making fs/char_dev.c emit a warning
or fail when it goes below 234... it doesn't currently. It just steals
more numbers. It's a serious archtectural issue if it persists.

Yours,
Linus Walleij