mmap2 on L4Linux rev 37

Adam Lackorzynski adam at
Tue Aug 6 21:48:19 CEST 2013

On Tue Aug 06, 2013 at 12:44:03 +0200, Sebastian Sumpf wrote:
> recently I started to use L4Linux r37 on ARM and experienced some issues
> with the 'sys_mmap_pgoff'-system call. When a user-level task tried to
> map a file the 'pgoff' parameter was usually bogus. Doing a little
> research I found that it was caused by the 'sys_mmap2' implementation in
> 'entry.S'. The function overwrites the 'pgoff' argument on the stack
> with r5 (as it is usually passed from user land), since in L4Linux this
> code gets called from the dispatch routine, 'pgoff' was set to whatever
> r5 was, and thus leading to bus errors later on.

Yep, indeed. Easy fix. :)

Adam                 adam at

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