Re: Kernel crash w/o reason

From: Daniel Eischen (deischen_at_freebsd.org)
Date: 12/23/04

  • Next message: Jan Engelhardt: "Re: Kernel crash w/o reason" 
    Date: Thu, 23 Dec 2004 17:12:06 -0500 (EST)
To: Jan Engelhardt <jengelh@linux01.gwdg.de>

    On Thu, 23 Dec 2004, Jan Engelhardt wrote:

    > Hello list,
    >
    >
    > for some reason, the Freebsd (5.3) kernel crashes whenever I do "simple
    > operations", in conjunction with a (self-written) kernel module.
    >
    > I have trimmed the original program down from approx 120 KB to the 7 KB (lots
    > of spacing and tabs :) to follow the common advise to find the shortest
    > codepiece showing the problem.
    > Well, you can retrieve the short prog at http://linux01.org/~jengelh/BUG.tbz2
    > Both files (rpldev.c and rpld.c) seem perfectly fine, but ...
    > see rpld.c for the details of the crash.
    >
    > Hope someone can shed some light on this.

    I don't think you are suppose to leave the kernel with mutex(es)
    held. A mutex is a short term lock, and at best you are abusing
    it's intended use. Moreover, I don't think you should leave the
    kernel with _any_ kernel synchronization object held. In the case
    of the mutex, the thread performing the close() may not be the
    thread that did the open() and which owns the mutex. 

    -- 
DE
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  • Next message: Jan Engelhardt: "Re: Kernel crash w/o reason"

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