Tracking down LORs

Roman Kurakin rik at
Fri Aug 20 01:29:24 PDT 2004

Scott Long wrote:

> Roman Kurakin wrote:
>> Hi,
>>     Currently I am trying to track down a couple of LORS
>> in my code. But it seems that I do not undestand smth or all
>> things id realy so bad.
>>     So I want to ask some questions to find out if my thoughts
>> correct or wrong.
>> 1. If I am right LOR means that we have at least two mutexs.
>> Lets call them a and b. If we set a, then b in first case
>> and b then a in second we could get dead loop, and thus LOR.
> Correct.
>> 2. If I have some driver that have mutex a, and we have some
>> sytem code that could call this driver with Giant (b), we would
>> get LOR if driver lock a and some other part of system will
>> try to lock Giant?
> The general rule is that NO other locks should be held when Giant
> is grabbed.

Probably I need a bit more grepping to find out how to turn off Giant
locking for other callbacks.

But at first I have to find out a reason of panic that I see on my screen
with recent Current(Generic). Heh ... ;-)


> Scott
> _______________________________________________
> freebsd-current at mailing list
> To unsubscribe, send any mail to 
> "freebsd-current-unsubscribe at"

More information about the freebsd-current mailing list