Linux 2.4.x Kernel Bug - Problem found

Linux 2.4.x Kernel Bug - Problem found

[DragonK]

Hello,

Two days ago I've sent you a mail regarding my problem
with the Kernel 2.4(5).x boot hangs.

I'd like to thank the kind people who answered me
back, I really appreciate their efforts.

I have two news: one good, one bad :)
The good one is that I've found the cause of the
kernel lock-up (er...sort of).

Tha bad one is that I can't do anything about it.
I had an ideea and disabled in my BIOS all caches,
floppy controller, ports and other stuff...
Surprise! Kernel 2.4.18 booted (in 10 mins :). No
lock-up!!

Ok...I went back into the BIOS and enabled internal
cache. Boot again...Guess what? :(
Nothing...dead.

So, at least on my system, there is a problem with the
cache. I don't think that the cache memory
itself is bad, since I don't experience random
failures or reboots...

What should I do? If there will be a patch for this,
where would I find it?
Please help!

BIOS Details:
AMI BIOS Release 11/16/97 S
BIOS Mainboard ID:
51-0505-001437-00111111-071595-M1531/43-001_10_TX_PRO-H

I have upgraded/downgraded the BIOS a couple of times
and this doesen't solve the problem.

Thank you.


PS: Here are some details about the CPU and PCIs, for
more info.
processor       : 0
vendor_id       : CyrixInstead
cpu family      : 5
model           : 4
model name      : 6x86L 2x Core/Bus Clock
stepping        : 2
fdiv_bug        : no
hlt_bug         : no
sep_bug         : no
f00f_bug        : no
coma_bug        : yes
fpu             : yes
fpu_exception   : yes
cpuid level     : 1
wp              : yes
flags           : fpu de cx8 mtrr
bogomips        : 149.50

00:00.0 Host bridge: Acer Laboratories Inc. [ALi]
M1531 [Aladdin IV] (rev b2)
        Subsystem: Acer Laboratories Inc. [ALi]:
Unknown device 1531
        Flags: bus master, slow devsel, latency 32

00:02.0 ISA bridge: Acer Laboratories Inc. [ALi] M1533
PCI to ISA Bridge [Aladdin IV] (rev b4)
        Flags: bus master, medium devsel, latency 0

00:03.0 Communication controller: CONEXANT: Unknown
device 1085 (rev 08)
        Subsystem: CONEXANT: Unknown device 1085
        Flags: bus master, medium devsel, latency 64,
IRQ 11
        Memory at ef7e0000 (32-bit, non-prefetchable)
        I/O ports at eff0
        Capabilities: [40] Power Management version 2
00:06.0 VGA compatible controller: S3 Inc. 86c764/765
[Trio32/64/64V+] (prog-if 00 [VGA])
        Flags: medium devsel
        Memory at ef800000 (32-bit, non-prefetchable)
        Expansion ROM at ef7f0000 [disabled]

00:0b.0 IDE interface: Acer Laboratories Inc. [ALi]
M5229 IDE (rev 20) (prog-if fa)
        Flags: bus master, medium devsel, latency 32
        I/O ports at ffa0

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Re: Linux 2.4.x Kernel Bug - Problem found

[Denis Vlasenko]

On 25 September 2002 19:06, DragonK wrote:
> Hello,
>
> Two days ago I've sent you a mail regarding my problem
> with the Kernel 2.4(5).x boot hangs.
>
> I'd like to thank the kind people who answered me
> back, I really appreciate their efforts.
>
> I have two news: one good, one bad :)
> The good one is that I've found the cause of the
> kernel lock-up (er...sort of).
>
> Tha bad one is that I can't do anything about it.
> I had an ideea and disabled in my BIOS all caches,
> floppy controller, ports and other stuff...
> Surprise! Kernel 2.4.18 booted (in 10 mins :). No
> lock-up!!

Congratulations!

> Ok...I went back into the BIOS and enabled internal
> cache. Boot again...Guess what? :(
> Nothing...dead.
>
> So, at least on my system, there is a problem with the
> cache. I don't think that the cache memory
> itself is bad, since I don't experience random
> failures or reboots...
>
> What should I do? If there will be a patch for this,
> where would I find it?
> Please help!

You have to patch arch/i386/setup.S with some piece of
'marker' asm code (say, infinite loop with blinking keyboard LED :-)
and move it further and further into boot process
until you find a place where it stops blinking.
You'll know then exact place of hang!
--
vda