Tiny Core Linux

Tiny Core Base => Micro Core => Topic started by: pmeslin on May 09, 2013, 05:52:14 AM

Title: Old kernel on new Core
Post by: pmeslin on May 09, 2013, 05:52:14 AM
Are there any counterindications, recommendations (or just plain "doesn't work") towards running an older (2.6.3x) kernel on a newer (4.x) version of MicroCore? I'm trying to install it on older hardware (ISA-only AMD 5x86 (486dx5) single board computer) and I've tried about a dozen different 3.x kernel configurations but none of them give any sign of life or even debugging messages past "Decompressing linux... ok. Loading kernel."

All debug and verbose flags maxed out, tried output both on VGA and TTYS0, got zlich. Haven't seen that happen before. The 2.6.x kernels boot without any issue though. Admittedly I haven't tried the very latest 2.6.x ones, sticking to 2.6.27-2.6.32.

It's really a case of trying to have the benefits of the much larger app library of microcore 4.x as the apps I want to use on that system are absent from the 3.x archives. (end goal: headless gps-backed ntp server with character lcd interface)
Title: Re: Old kernel on new Core
Post by: bmarkus on May 09, 2013, 06:04:41 AM
If you add the modules related to your kernel to initrd it must work.
Title: Re: Old kernel on new Core
Post by: gerald_clark on May 09, 2013, 06:24:59 AM
How much RAM does this board have?
Title: Re: Old kernel on new Core
Post by: pmeslin on May 13, 2013, 05:44:19 AM
64MB. Admittedly it's slow EDO DRAM but it's more than sufficient for my needs. 'Real' UARTs and a PC-104 bus are also pretty convenient.

I know, I could go with a RasPi, but what's the challenge in that? ;)
Title: Re: Old kernel on new Core
Post by: tinypoodle on May 13, 2013, 07:12:23 AM
If you add the modules related to your kernel to initrd it must work.


With 64MB RAM only, replacing rather than adding modules may be preferable then.
Title: Re: Old kernel on new Core
Post by: Rich on May 13, 2013, 07:25:52 AM
Hi pmeslin
While adding/replacing the kernel related modules to the initrd should allow you to boot, there is still the matter of
applications/dependencies that are kernel version dependent to deal with. You would need to recompile those
against your kernel version, assuming they don't actually require a 3.x kernel.
Title: Re: Re: Old kernel on new Core
Post by: bmarkus on May 13, 2013, 07:46:17 AM
, there is still the matter of
applications/dependencies that are kernel version dependent to deal with. You would need to recompile those
against your kernel version, assuming they don't actually require a 3.x kernel.
Tell us which kernel version dependent applications you mean.
Title: Re: Old kernel on new Core
Post by: pmeslin on May 13, 2013, 08:03:08 AM
I'd be using a custom kernel either way due to the need for PPS support and other various tweaks (to support 10 serial ports), so initrd would be pretty much built from scratch.

I'll give it a try over the next few weeks due to shipping delays.
Title: Re: Old kernel on new Core
Post by: Rich on May 13, 2013, 09:25:20 AM
Hi bmarkus
Quote
Tell us which kernel version dependent applications you mean.
http://forum.tinycorelinux.net/index.php/topic,14792.msg84061.html#msg84061
I don't know if there are any apps that may be kernel sensitive.
Title: Re: Old kernel on new Core
Post by: gerald_clark on May 13, 2013, 09:35:54 AM
Many apps have deps of kernel modules.
Title: Re: Old kernel on new Core
Post by: curaga on May 13, 2013, 11:43:29 AM
There are limits on how old a kernel you can use, by core components such as glibc and udev. You may want to double-check these, otherwise the boot will fail after the kernel.

BTW, if the very latest 3.9 kernel still fails on your hw, I'm sure the kernel folks would appreciate if you could bisect which change broke it.
Title: Re: Old kernel on new Core
Post by: pmeslin on May 19, 2013, 04:54:15 AM
There are limits on how old a kernel you can use, by core components such as glibc and udev. You may want to double-check these, otherwise the boot will fail after the kernel.

BTW, if the very latest 3.9 kernel still fails on your hw, I'm sure the kernel folks would appreciate if you could bisect which change broke it.

With the removal of i386 support in the 3.7x / 3.8x? kernel series, I'm not sure how well an ISA-based i486 will be supported in the 3.9x. I'll have to give it a try but that kernel might be pretty bloated for such ancient hardware anyway­, even with a custom built "removed almost everything" kernel.
Title: Re: Old kernel on new Core
Post by: curaga on May 19, 2013, 05:59:53 AM
486 can't be removed in a while, due to the many embedded boards; ISA can't be removed as it still lives in current motherboards (superIO, various internal buses are really ISA). So they should work for some time.