problem with discrete video card

Andriy Gapon avg at
Thu Nov 26 09:41:00 UTC 2015

I've been given a Radeon 6850 based video card that supposedly used to work.
But for me it works only in the text mode.  Any attempt to use it with radeonkms
driver results in a reboot (no panic or trap).  I've done a little bit of
investigation and I see that the crash happens in radeonfb_create() when the
following code is executed:

	memset(rbo->kptr, 0x0, radeon_bo_size(rbo));

It seems like this could be the very first write to the video memory, but I am
not sure.  I suspect that the problem could be a hardware one.  But maybe this
could be a software or configuration problem?

I've collected kernel messages from the driver:
(Please note that I've moved the memset line after the code that reports fb
properties to see if they are sane)

Andriy Gapon

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