From: "Theodore Y. Ts'o" <tytso@mit.edu>
To: Arnd Bergmann <arnd@arndb.de>
Cc: Zhenzhong Duan <zhenzhong.duan@gmail.com>,
Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>
Subject: Re: Question about dynamic minor number of misc device
Date: Mon, 20 Jan 2020 17:13:23 -0500 [thread overview]
Message-ID: <20200120221323.GJ15860@mit.edu> (raw)
In-Reply-To: <CAK8P3a0aFr546fF+=LDm3rwZ-sK-xC8VLYTZjOEn+o6fVixRHg@mail.gmail.com>
On Mon, Jan 20, 2020 at 11:59:32AM +0100, Arnd Bergmann wrote:
> On Mon, Jan 20, 2020 at 11:26 AM Zhenzhong Duan
> <zhenzhong.duan@gmail.com> wrote:
> > On Mon, Jan 20, 2020 at 6:03 PM Arnd Bergmann <arnd@arndb.de> wrote:
> > > On Mon, Jan 20, 2020 at 9:33 AM Zhenzhong Duan <zhenzhong.duan@gmail.com> wrote:
> > > On a related note, I checked for drivers that call misc_register()
> > > with a minor number that is not defined in include/linux/misc.h
> > > and found a bunch, including some that have conflicting numbers,
> > > conflicting names or numbers from the dynamic range:
> > >
> > > drivers/staging/speakup/devsynth.c:#define SYNTH_MINOR 25
> > > drivers/staging/speakup/speakup_soft.c:#define SOFTSYNTH_MINOR 26 /*
> > > drivers/staging/speakup/speakup_soft.c:#define SOFTSYNTHU_MINOR 27 /*
> > > drivers/macintosh/via-pmu.c:#define PMU_MINOR 154
> > > drivers/macintosh/ans-lcd.h:#define ANSLCD_MINOR 156
> > > drivers/auxdisplay/charlcd.c:#define LCD_MINOR 156
> > > drivers/char/applicom.c:#define AC_MINOR 157
> > > drivers/char/nwbutton.h:#define BUTTON_MINOR 158
> > > arch/arm/include/asm/nwflash.h:#define FLASH_MINOR 160
> > > drivers/sbus/char/envctrl.c:#define ENVCTRL_MINOR 162
> > > drivers/sbus/char/flash.c:#define FLASH_MINOR 152
> > > drivers/sbus/char/uctrl.c:#define UCTRL_MINOR 174
> > > drivers/char/toshiba.c:#define TOSH_MINOR_DEV 181
> > > arch/um/drivers/random.c:#define RNG_MISCDEV_MINOR
> > > drivers/auxdisplay/panel.c:#define KEYPAD_MINOR 185
> > > drivers/video/fbdev/pxa3xx-gcu.c:#define MISCDEV_MINOR 197
> > > kernel/power/user.c:#define SNAPSHOT_MINOR 231
> > > drivers/parisc/eisa_eeprom.c:#define EISA_EEPROM_MINOR 241
> > >
> > > If you would like to help clean that up, you are definitely welcome
> > > to send patches.
> >
> > Ok, should that be a patch for all drivers or seperate patch for each driver?
>
> I think one patch to move the ones with unique names would be fine,
> but then separate patches for
>
> - FLASH_MINOR move and rename to avoid conflict
> - change speakup to dynamic minors
> - support for high dynamic minor numbers if you are really motivated
> (probably nobody needs these)
Are we sure that reassigning minor device number conflits isn't going
to break systems? Especially those on random, older, architectures
they might not be using udev.
- Ted
next prev parent reply other threads:[~2020-01-20 22:13 UTC|newest]
Thread overview: 9+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-01-20 8:33 Question about dynamic minor number of misc device Zhenzhong Duan
2020-01-20 10:03 ` Arnd Bergmann
2020-01-20 10:25 ` Zhenzhong Duan
2020-01-20 10:59 ` Arnd Bergmann
2020-01-20 22:13 ` Theodore Y. Ts'o [this message]
2020-01-21 7:56 ` Arnd Bergmann
2020-01-21 16:31 ` Theodore Y. Ts'o
2020-01-21 17:54 ` Sam Hartman
2020-01-21 15:42 ` Greg Kroah-Hartman
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20200120221323.GJ15860@mit.edu \
--to=tytso@mit.edu \
--cc=arnd@arndb.de \
--cc=gregkh@linuxfoundation.org \
--cc=linux-kernel@vger.kernel.org \
--cc=zhenzhong.duan@gmail.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox