trap (GPF) when starting l4linux -- resolved!

valerius _valerius at
Wed Sep 24 03:09:10 CEST 2008

The question was resolved by myself and no more help needed :)

I spent a night reconfiguring Fiasco and L4Linux and reading the Mailing list 
archive. And it appears that l4linux itself was configured correctly. But I 
encountered a troubles with 'Mysterious double fault' when using QEMU that 
could be overcome if disable 'Assembler IPC shortcut' option in Fiasco 
configuration. Also I found that options in loader config file have 
significant order of precedence. They should appear in the following order:


If all_sects_writable appears before allow_cli then loader says that l4linux 
task is not allowed to do any I/O. It is really strange and non-obvious.
Also, some diversity in options order may lead to unresolved page faults and 
GPFs like the GPF which I was asking for.

Someone can say it is very trivial but I spent a night to figure out the way
it works. 

I just wanted to point these non-obvious moments to novices. (and, maybe, 
developers of loader server -- what if to make these options order to be 
non-significant? It could make loader behaviour more predictable.) 


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