Re: [OOPS] 2.6.21-rc6-git5 in cfq_dispatch_insert

[Brad Campbell <brad@wasp.net.au>]

Neil Brown wrote:

> How likely it would be to get two requests with the same sector number
> I don't know.  I wouldn't expect it to ever happen - I have seen it
> before, but it was due to a bug in ext3.  Maybe XFS does it
> intentionally some times?

It certainly sounds like an odd thing to occur.

Even stranger that it's easier to hit on a degraded array or an array being checked.

I *am* using ext3 on this box (and all my boxes in fact)

> You could test this theory by putting a
>    WARN_ON(cfqq->next_rq == NULL);
> at the end of cfq_reposition_rq_rb, just after the cfq_add_rq_rb call.

I've done that.. now to wait for it to hit again.

Brad
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