amd64/87977 : [busdma] [panic] amd64 busdma dflt_lock called (by ata) if physmem>4G

Thomas Hurst tom at
Tue Dec 27 12:31:25 PST 2005

* Attila Nagy (bra at wrote:

> I believe this is fixed in CURRENT. On 6-STABLE you can set hw.physmem
> to use a smaller amount of memory or switch to the ata driver before
> 2005.10.08.

Thanks for the pointer.  I grabbed sys/dev/ata and sys/sys/ata.h off
my CURRENT laptop and popped it on my RELENG_6 Opteron and it appears
to work fine with all 4G -- I can pull data off all 4 disks at >250M/s
without trouble when I could previously not even get past mounting

Hope to see this merged before too long, but for now at least this pr is
a little bit more useful :)

Thomas 'Freaky' Hurst

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