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

From: Huang\, Ying
Date: Tue Feb 23 2016 - 01:36:25 EST


Linus Walleij <linus.walleij@xxxxxxxxxx> writes:

> On Mon, Feb 15, 2016 at 3:39 AM, Huang, Ying <ying.huang@xxxxxxxxx> wrote:
>> Michael Welling <mwelling@xxxxxxxx> writes:
>
>>> Could you run cat /proc/devices?
>>
>> Sorry, the test mechanism is not flexible enough to run some shell
>> command in test system. Could you provide a specialized debug kernel to
>> dump the necessary information in kernel log? We can collect dmesg
>> easily.
>
> Can you try this:
>
> diff --git a/fs/char_dev.c b/fs/char_dev.c
> index 24b142569ca9..74a2d433273e 100644
> --- a/fs/char_dev.c
> +++ b/fs/char_dev.c
> @@ -96,6 +96,8 @@ __register_chrdev_region(unsigned int major,
> unsigned int baseminor,
> goto out;
> }
> major = i;
> + pr_info("CHARDEV: allocate major %d for \"%s\"\n",
> + i, name);
> }
>
> cd->major = major;
>
> Then dmesg |grep CHARDEV should tell what we need to know.

Sorry for late, the dmesg with the patch is attached. And the output of
dmesg | grep CHARDEV is as follow:

[ 0.750037] CHARDEV: allocate major 254 for "gpiochip"
[ 0.897928] CHARDEV: allocate major 253 for "tpm"
[ 0.904196] CHARDEV: allocate major 252 for "ndctl"
[ 0.905295] CHARDEV: allocate major 251 for "dimmctl"
[ 0.909573] CHARDEV: allocate major 250 for "pps"
[ 0.913740] CHARDEV: allocate major 249 for "ptp"
[ 0.916711] CHARDEV: allocate major 248 for "iio"
[ 1.227597] CHARDEV: allocate major 247 for "bsg"
[ 1.577194] CHARDEV: allocate major 246 for "gsmtty"
[ 1.614921] CHARDEV: allocate major 245 for "ttyn"
[ 1.616044] CHARDEV: allocate major 244 for "ttyARC"
[ 1.617177] CHARDEV: allocate major 243 for "ttyRP"
[ 1.618310] CHARDEV: allocate major 242 for "ttyLP"
[ 1.620618] CHARDEV: allocate major 241 for "noz"
[ 1.621707] CHARDEV: allocate major 240 for "ttyIPWp"
[ 1.630024] CHARDEV: allocate major 239 for "telco_clock"
[ 1.632315] CHARDEV: allocate major 239 for "cmm"
[ 1.681375] CHARDEV: allocate major 238 for "hpilo"
[ 1.696757] CHARDEV: allocate major 237 for "aac"
[ 1.699338] CHARDEV: allocate major 236 for "megadev_legacy"
[ 1.704680] CHARDEV: allocate major 235 for "megaraid_sas_ioctl"
[ 1.731179] CHARDEV: allocate major 234 for "pmcsas"
[ 1.737520] CHARDEV: allocate major 233 for "nvme"
[ 2.388531] CHARDEV: allocate major 232 for "firewire"
[ 2.389743] CHARDEV: allocate major 231 for "uio"
[ 2.904429] CHARDEV: allocate major 230 for "ttySDIO"
[ 2.922374] CHARDEV: allocate major 229 for "ib_qib"
[ 2.927559] CHARDEV: allocate major 228 for "hidraw"
[ 2.952328] CHARDEV: allocate major 227 for "fwtty"
[ 2.953435] CHARDEV: allocate major 225 for "fwloop"

Best Regards,
Huang, Ying

Attachment: dmesg.xz
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