Semaphore library error on L4Env/Fiasco-UX

Andreas Niederl niederl at
Mon Aug 7 18:57:27 CEST 2006


Alexander Boettcher wrote:
> Hash: SHA1
> Hi,
> Andreas Niederl wrote:
>>using the current CVS version of Fiasco and L4Env I get the following 
>>error on startup of the system with Fiasco-UX:
>>exec    | Startup: semaphore lib initialization failed (-1)!
>>The task on which it fails varies depending on which startup script from 
>>l4/tool/runux is executed but it's always the first or second task that 
>>L4Env is compiled with gcc-3.3.6 and Fiasco with gcc-4.0.2.
>>Is this a known problem?
> no. At least I cannot reproduce it.
> Ok, a little bit tracking: The message is from
> l4env/lib/src/startup.c:320. That means that l4semaphore_init returns
> - -1. This function is defined in semaphore/lib/src/semaphore.c:494. If
> the function returns -1, one of the following message should be logged:
> "Missing 'deceit_bit_disables_switch' kernel feature!"
> or
> "L4semaphore: failed to create semaphore thread"
> Which one is it in your configuration ?

Neither. Using the con script from l4/tools/runux the modules get loaded 
and right after that I am greeted by:
con     | Startup: semaphore lib initialization failed (-1)!


But I do have the 'deceit_bit_disablese_switch' feature disabled and by 
enabling it it works for my configuration.
Thank you very much.


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