Re: Sleeping on "isp_mboxwaiting" with the following non-sleepablelocks held:

In message <000801c3981a$8abc6540$23a610ac_at_win2k>, "Matthew Jacob" writes:
>So? How about some details and context?
>
>I thought was told that being able to use locks in HBAs is fine. I had
>them on for a while, and then had them off. I turned them on again over
>a month ago. I'm somewhat surprised to see that a problem shows up now.
>
>*I* do the right thing with locks, IMO. I hold them in my module when I
>enter and release them if/when I leave. Seeing a lock held by some
>random caller causing me to blow up to me seems to be a hole in the
>architecture, but I'd be the first to admit that I hardly am up to date
>on what the rules of the road are now so such an opinion is
>ill-informed.

The lock held in this case, is not "some random caller", that is a
mutex held specifically to expose device drivers which try to sleep
in their ->strategy() function.

You cannot sleep in the strategy() function because that would hold
op I/O, and therefore likely lead to deadlock.

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