Subject: Network problem with Debian installation on RiscPC

From: David Seery <[email-masked]>
Date: Sun, 14 May 2000 15:19:07 +0100

Hello,

This may be a trivial / off-topic question; if so, I apologise.

I've just installed the Debian port on my RiscPC with the result that
everything works except a bizarre kernel panic when using (at least)
ftp and probably some other stuff too.  Everything is OK using the
ARM image at ftp.jimpick.com until I install the default Debian packages,
and after that any attempt to use apt causes a kernel panic when
logging in to the Debian ftp site.

  'kernel panic: Unknown data abort'

I also get them same behaviour when ftp'ing some other remote sites;
but others are OK.  Under X everything just hangs with the cursor
flashing in the top-left of the screen; this behaviour occurs with
gftp, gicq and ftp in an xterm.  (Oddly the same thing happens with
gcd.)

I've reinstalled everything four times now and I get the same behaviour
every time.  Initially I assumed I'd accidentally installed some
netwinder material that was causing a problem, but this does not
appear to be the case.  I've also tried compiling a fresh kernel
(2.2.13, patch rmk2) which built cleanly but crashed more or less when
trying to mount the root filesystem when I tried to use it.  This
seems very odd; I must have done something wrong.  I'm currently
using the most recent (010300) 2.2.13 lkab kernel from inkvine.fluff.org
to boot into Linux; the 2.2.14 kernel from the same source boots
but exhibits the same behaviour.  All the 2.3 kernels I have tried
hang the machine as soon as it attempts to boot the kernel.
Additionally I've also tried the original 2.0.36 kernel from
arm.linux.uk.org but this hangs on trying to mount the root filesystem.

If I boot the kernel with the command line argument init=/bin/sh (or
some other shell) then everything seems OK; I've tried selectively omitting
init scripts from /etc/init.d but none of them seem to cure the
problem.  But obviously something is getting loaded which is causing
the problem.

Does anybody have any idea what might be going on?

Many thanks,

David

-- 
David Seery                       Room H6
[email-masked]                   Christ's College

unsubscribe: body of `unsubscribe linux-arm' to [email-masked]
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---

From: Russell King - ARM Linux Admin <[email-masked]>
Date: Sun, 14 May 2000 16:10:50 +0100 (BST)

>   'kernel panic: Unknown data abort'

Which processor type are you using?
   _____
  |_____| ------------------------------------------------- ---+---+-
  |   |        Russell King       [email-masked]      --- ---
  | | | |            http://www.arm.linux.org.uk/            /  /  |
  | +-+-+                                                     --- -+-
  /   |               THE developer of ARM Linux              |+| /|\
 /  | | |                                                     ---  |
    +-+-+ -------------------------------------------------  /\\\  |

---

From: Philip Blundell <[email-masked]>
Date: Sun, 14 May 2000 17:14:05 +0100

>  'kernel panic: Unknown data abort'

This is an ARM610 or ARM710 machine, right?

Some program - probably the ftp client - performed a bad memory access that 
the kernel didn't understand.  Was that the complete message that was 
displayed, or did it include more information that you've omitted?

The 2.3 lkab kernels shouldn't actually panic when this happens, though I 
don't know offhand whether they are likely to handle the situation properly.  
If they won't boot for you this is obviously a moot point anyway.

p.

---

From: Philip Blundell <[email-masked]>
Date: Sun, 14 May 2000 17:57:37 +0100

>  'kernel panic: Unknown data abort'

You could try a patch like this.  I haven't tested this, and I don't know if 
it's enough to get things going, but it might be worth a go.

p.

--- linux/arch/arm/mm/proc-arm6,7.S	Mon Jan 10 18:49:58 2000
+++ linux/arch/arm/mm/proc-arm6,7.S	Sun May 14 17:55:43 2000
@@ -110,7 +110,7 @@
 		add	pc, pc, r1, lsr #22		@ Now branch to the relevent processing routine
 		movs	pc, lr
 		b	Ldata_unknown
-		b	Ldata_unknown
+		b	Ldata_simple			@ swp
 		b	Ldata_unknown
 		b	Ldata_unknown
 		b	Ldata_earlyldrpost		@ ldr	rd, [rn], #m
@@ -141,7 +141,7 @@
 		add	pc, pc, r1, lsr #22		@ Now branch to the relevent processing routine
 		movs	pc, lr
 		b	Ldata_unknown
-		b	Ldata_unknown
+		b	Ldata_simple			@ swp
 		b	Ldata_unknown
 		b	Ldata_unknown
 		b	Ldata_lateldrpostconst		@ ldr	rd, [rn], #m

---

From: Russell King - ARM Linux Admin <[email-masked]>
Date: Sun, 14 May 2000 17:03:56 +0100 (BST)

> it's enough to get things going, but it might be worth a go.

Unfortunately, the latest 2.2 and 2.3 kernels do not boot with ARM610s.
Please supply the patches you're using to make them boot please.
   _____
  |_____| ------------------------------------------------- ---+---+-
  |   |        Russell King       [email-masked]      --- ---
  | | | |            http://www.arm.linux.org.uk/            /  /  |
  | +-+-+                                                     --- -+-
  /   |               THE developer of ARM Linux              |+| /|\
 /  | | |                                                     ---  |
    +-+-+ -------------------------------------------------  /\\\  |

---

From: Philip Blundell <[email-masked]>
Date: Sun, 14 May 2000 19:30:29 +0100

>Please supply the patches you're using to make them boot please.

I don't have any working ARM610 hardware any more, I'm afraid.

p.