Revealing unload_lock to everyone

Dave Hansen
2002-01-31T23:58:47Z

This came up in a conversation about ieee1394_core.c. In 2.5.3, the BKL
is used to protect a module from being unloaded. The code looks like this:

lock_kernel();
read_lock(&ieee1394_chardevs_lock);
file_ops = ieee1394_chardevs[blocknum].file_ops;
module = ieee1394_chardevs[blocknum].module;
read_unlock(&ieee1394_chardevs_lock);
...
INCREF(module);
unlock_kernel();

The question is, how can we keep the module from being unloaded between
the file_ops assignment, and the INCREF. Do we have a general purpose
way, other than the BKL, to keep a module from being unloaded? There is
unload_lock, but it is static to module.c. We can always make it
global, but is there a better solution?

--
Dave Hansen
haveblue@us.ibm.com