LOR in VM (with backtrace)
Alan L. Cox
alc at imimic.com
Tue Jun 24 20:45:07 PDT 2003
Andrew Gallatin wrote:
>
> Alan L. Cox writes:
> > Thanks for letting me know. This is another false positive: Witness
> > can't distinguish the lock on the object being destroyed from the lock
> > on the object used by UMA because their labels are the same. They will
> > never, however, be the same object. So, deadlock isn't a risk.
>
> In a closed source driver I maintain, I had to resort to passing a
> string containing the meaningful name concatonated with some unique info
> to mtx_init().
>
> It seems like witness could just concat the address of the mutex along
> with the strings passed to mtx_init() so as to make sure things were
> unique..
>
I'm not sure that witness could handle the 30,000 to 200,000 distinct
mutex labels that would result from doing this for every vm object.
Regards,
Alan
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