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Re: slackware 14 is out

Posted: 23 Jan 2013, 17:30
by markds
afaik this is not possible as devices never gets renamed no matter what you do.
Definitely right, the issue is actually this - my usb is detected as sda and the hdd as sdb.

Now I'm quite certain this is a kernel config issue. Slax7 has this problem of the usb being detected as sda. I used the .config from Slax7 to build a new Porteus kernel and when I booted with this kernel, the same issue occrus - my usb is detected as sda. Now if I use the Porteus kernel config (modprobe configs; zcat /proc/config.gz) and I rebuild the kernel, then my usb is detected as sdb and the hdd as sda (which is the way its supposed to be).

I'd like to figure out exactly which kernel config controls this however - any one have any ideas? I suppose its one of the SATA or ATA configs, but comparing between Slax and Porteus configs, I can't see which one makes a difference.

Thanks.

Re: slackware 14 is out

Posted: 24 Jan 2013, 11:40
by markds
I found a query online that highlights this problem of usb being detected as sda as an issue from kernel 3.6 onwards.

https://lkml.org/lkml/2012/10/25/595

It essentially blames a commit made to floppy.c for this behavior. Tomas M. looked at it and found that apparently if CONFIG_BLK_DEV_FD is set to 'm', the problem disappears. If set to 'y' then the problem persists. Comparing Slax7 and Portues config files, it was found that Porteus has this as 'm', while Slax7 has this a 'y'.

While skeptical that a floppy issue may affect the USB, I am now recompiling the kernel with this option as 'm' to see if it actually does fix the issue. Shouldn't affect Porteus users of course since the option in the Porteus config is already set to 'm', but I thought it would be good for info sake.

Thanks.

Re: slackware 14 is out

Posted: 24 Jan 2013, 17:09
by markds
Ok confirmed that "CONFIG_BLK_DEV_FD=y"was the problem.

I recompiled the kernel with "CONFIG_BLK_DEV_FD=m" and now hdd is /dev/sda and usb is /dev/sdb, as it should be.

Re: slackware 14 is out

Posted: 24 Jan 2013, 17:40
by fanthom
thanks Mark for clarification.

btw: must say that it's still a mystery for me why "CONFIG_BLK_DEV_FD=" was marked as "y" in slax's config in the first place.
slax's kernel is is over 3 times bigger than any floppy can handle (so you can't boot slax from this type of device) so what's the point of having it compiled into?
or maybe the intention was to load kernel/initrd from CD/USB and some security keys from floppy?
that would even make sense 8)

(ofc i'm joking - i'm pretty sure this setting was just overlooked by Tomas)

Re: slackware 14 is out

Posted: 25 Jan 2013, 12:42
by markds
I think it was merged from the previous config. In any case, I believe Tomas will remove it for future kernel builds since floppy drives are hardly used anymore.

I've also suggested he build in the aufs, squashfs, etc instead of loading the modules from the initrfs.img. That would definitely save the trouble of rebuilding the initrfs everytime the kernel changes.

Very happy to see the extlinux solution employed for Porteus :)