FreeBSD RELEASE-8.0-p3 panic

[John Baldwin]

On Thursday, July 15, 2010 1:13:05 pm Masoom Shaikh wrote:
> Howdy,
> 
> here is the image of my FreeBSD panic
> http://images.cjb.net/d64f4.jpg
> 
> the error says RAM parity error(not visible in pic). but I have
> following reasons to believed it could be wrong
> 
> 1. I have 1GB of RAM, with two chips of 512MB each. It panics even if
> I boot with only 512MB of total RAM. i.e. one chip removed. It panics
> for both chips individually.
> 2. I tried replacing my both 512MB chips with two 512MB chips from my
> friends laptop, it still panics with exact same error. RAM parity
> error, it is very unlikely that his chips have this problem. He runs
> Ubuntu on those chips and Windows7 with no issues whatsoever.
> 3. Windows7 operates on this(my) laptop just fine.
> 
> sometimes it take 3-4 attempts to boot it, since it panics the moment
> KDM tries to load. But once running it runs few hours if I do not
> subject it to load. Even moderate load like browsing some  multimedia
> content websites, e.g. youtube or some site with lots of flash based
> ads or even some javascript heavy page like GMail etc... It appears
> the moment I start subjecting the machine to load, mem usage increases
> and it hits the part of RAM which might possibly have parity error.
> 
> have a look at the pic, the frame pointer is always remains same
> 0xffffffff803f1ef1. I have already asked, and again ask, is there a
> way to ask FreeBSD to "ignore" some part of RAM ? how do I zero in on
> the exact point of failure ? I am aware, just too many variables are
> here, some wild guesses ?
> 
> I am very sorry for my feeble OS debugging skills if any, but FreeBSD
> has nothing to do with my day job, it is just a hobby for me. I
> sincerely want it to work.

There is a tunable you can set in the loader (vm.blacklist) to a list of 
physical addresses of pages that should be ignored.

-- 
John Baldwin