Skip site navigation (1)Skip section navigation (2)
Date:      Fri, 03 May 2002 23:26:09 -0700
From:      Michael Smith <msmith@freebsd.org>
To:        mjacob@feral.com
Cc:        hackers@freebsd.org
Subject:   Re: naive i386 && FreeBSD interrupt question 
Message-ID:  <200205040626.g446Q9h00791@mass.dis.org>
In-Reply-To: Your message of "Thu, 18 Apr 2002 12:27:33 PDT." <Pine.BSF.4.21.0204181218220.86121-100000@beppo> 

next in thread | previous in thread | raw e-mail | index | archive | help
> 
> This was -stable- but it's really a hacker's question.
> 
> I really am *not* much of an i386 weenie and I'll have to admit that I don't
> fully understand the interrupt mask scheme and I ran into a troubling problem
> .
> 
> I was running some very extensive tests on a dual processor (but not SMP
> configured) system- I was in the middle of calling busdma_load from the isp
> driver when I got interrupted and blew up fielding an isp interrupt.

You call isp_intr out of isp_watchdog; any chance that the timeout could 
have gone off and dumped you in there?

Otherwise, no, you should not have had your interrupt handler reentered 
while it was masked.  You shouldn't have to call splsoftvm() when calling 
the busdma code; it should take whatever locks it needs at the time.

Knowing the contents of cpl vs. the CAM spl mask and the actual interrupt 
in question would be useful, as would the stack backtrace from the 
explosion (ie. when you say "got interrupted" was the backtrace through 
the actual interrupt entry point?)

 = Mike




-- 
To announce that there must be no criticism of the president,
or that we are to stand by the president, right or wrong, is not
only unpatriotic and servile, but is morally treasonable to 
the American public.  - Theodore Roosevelt



To Unsubscribe: send mail to majordomo@FreeBSD.org
with "unsubscribe freebsd-hackers" in the body of the message




Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?200205040626.g446Q9h00791>