Re: FSCK message suppressed during booting? (2.6.9-rc2)

[Chiaki]

> I will wait the response from Debian package
> maintainer.

Dear all,

Thanks to the investigative work of
Debian sysvinit package maintainer, Miquel van Smoorenburg,
we have found that I had an incorrect major and minor
number for /dev/console on my PC under 2.6.9-rc2!

When I re-created /dev/console with correct major and minor number,
fsck message appears without a problem during booting
together with other formerly invisible kernel messages.

Why did my PC work *FLAWLESSLY* under 2.4.2x series?
I have been using this setup at least for a few years now.
(I can't remember the exact history. CPU, motherboard have
changed during the life time of my computer now.)

So I investigated a little.

Under 2.6.9-rc2 : Incorrect major, minor number for console on my PC.

    Under 2.6.9-rc2, I had the following major, minor for /dev/console.

        ls -l /dev/console
    crw-------  2 root root 4, 64 2004-10-02 01:46 /dev/console

    This turned out to be the culprit for my problem.

    Then WHY ON EARTH did my PC log fsck messages to
    the console under 2.4.2x?

Rebooting into 2.4.2x: correct major and minor number!

    To check this, I rebooted into 2.4.25 *with devfsd running* and
    found the correct /dev/console (major/minor) number under it.

    ls -l /dev/console
    crw-------  1 root tty 5, 1 2004-10-03 04:15 /dev/console

    Aha, correct /dev/console major and minor number!

    It seems that devfsd saved me from the underlying incorrect setting.

    I usually boot 2.4.25 with devfsd from the boot command line.  The
    devfsd function in the kernel presumably re-created /dev/console
    with the correct major and minor number at boot time(?).
    Thus fsck output was visible.

    My boot command line for booting 2.4.xx was like this.
    Kernel command line: mem=nopentium devfs=mount drm=debug 
root=/dev/sda6 ro scsihosts=sym53c8xx:tmscsim BOOT_IMAGE=2425

    Under 2.4.25, I get these devfs messages in dmesg output.

        "dmesg | egrep devfs" output.
    devfs: v1.12c (20020818) Richard Gooch (rgooch@xxxxxxxxxxxxx)
    devfs: devfs_debug: 0x0
    devfs: boot_options: 0x1
    Mounted devfs on /dev
    usb.c: registered new driver usbdevfs


Rebooted into 2.6.9-rc2: Recreated /dev/console manually.

I rebooted into 2.6.9-rc2 to manually re-create /dev/console with
correct major and minor number.  I had installed udev for a day,
but it doesn't seem to try to re-create /dev/console and,
for that matter, invocation of udev would be too late
for me to see fsck output during booting
even if it re-created /dev/console with correct major and minor numbers.

    duron:/home/ishikawa# rm /dev/console
    duron:/home/ishikawa# cd /dev
    duron:/dev# ./MAKEDEV console
    duron:/dev# ls -l /dev/console
    crw-------  1 root tty 5, 1 2004-10-03 04:27 /dev/console
    duron:/dev#

After I recreated and "touch /forcefsck; reboot", I saw
the fsck message now without a problem!

Morale of the story:

       Commercial distribution makers  and maybe udev package
       maintainers (since udev is only meant for 2.6.y kernels
       and later,) might want to include a simple checker for
       the correct permissions, major and number settings
       of a few key devices to save time for support calls
       from those who have been saved by devfsd under previous
    2.4.x kernel up until that time.
       (Once the cause is known, the fix is easy. But knowing
       the cause takes time.)

       I have no idea how many percentage of linux users have strange
       permissions and/or major/minor numbers for a few important
       devices, but when majority of them would move into 2.6.y series
       kernel in the next year or so, some users who have been saved
       by devfsd will see certain things no longer work.
       Majority of installed linux users are 2.4.x series kernels
       but they certainly would tinker with 2.6.2y kernels when
       they become available :-)

cf.

I have no idea why I had incorrect major and minor number for console
*in the first place*.  Current MAKEDEV has correct (major, minor) for
"console".

    # cd /dev
    # egrep console MAKEDEV
        $0 $opts console
        $0 $opts console
        $0 $opts console
        $0 $opts console
        $0 $opts console
        $0 $opts console
        $0 $opts console
        $0 $opts console
        $0 $opts console
        $0 $opts consoleonly
        $0 $opts console
        $0 $opts console
     consoleonly)
            makedev console c 5 1 $cons
                makedev console c 5 1 $cons
                symlink console tty0
     console)
        $0 $opts consoleonly


     Hmm... Was there a transition of major/minor numbers
     somewhere between 2.2.y -> 2.4.z  ?

--
int main(void){int j=2003;/*(c)2003 cishikawa. */
char t[] ="<CI> @abcdefghijklmnopqrstuvwxyz.,\n\"";
char *i ="g>qtCIuqivb,gCwe\np@.ietCIuqi\"tqkvv is>dnamz";
while(*i)((j+=strchr(t,*i++)-(int)t),(j%=sizeof t-1),
(putchar(t[j])));return 0;}/* under GPL */
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