Re: bcm33xx port

From: Maciej W. Rozycki
Date: Sun Jun 08 2008 - 16:14:38 EST


On Sun, 8 Jun 2008, Kevin D. Kissell wrote:

> > The RI error spits out a bunch of info, including epc which presumably points
> > to the instruction causing the problem: ac85ffc0; this is 'sw a1,-64(a0)'
> >
> But unless the processor itself is actually defective, there is no way that
> a SW instruction can cause an RI exception. Sometimes a kernel crash
> is so violent that the kernel stack frame cannot be reliably decoded by
> the crash dump code, and this would appear to be one of those cases.
> I find the address of 0xac85ffc0 to be a bit suspicious, myself. That's
> a kseg1 (non-cacheable identity map) address for physical address
> 0x0c85ffc0, which would be legitimate (though suspicious) if you had
> 256MB of RAM, but the boot log quote you posted earlier suggests
> that you've only got 16M. Is there really memory of some kind at
> that address? Are you calling routines in a boot ROM from Linux?

Well, 0xac85ffc0 is the instruction word corresponding to 'sw a1,-64(a0)'.
:) The actual address of the failure is apparently 0x004e010c, which is
pretty much a standard location somewhere within a user executable proper.

Maciej
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