On Friday 16 June 2006 20:47, Ian Dowse wrote: > In message <[EMAIL PROTECTED]>, John Baldwin writes: > >But unloadentry() would never unload such a module because fp->file > >is NULL. unloadentry() would only call clearentry() and then > >linker_file_unload() on an explicitly loaded firmware module. > > - driver calls firmware_get, firmware image loaded and fp->file set to > non-NULL > - manually kldload some_module_that_depends_on_firmware_image > - driver calls firmware_put, unloadentry called and sets fp->file = NULL > > If at this point the entry was cleared then all future calls to > firmware_get would fail even though the module is still available, > referenced and loaded. > > I'm not saying that these cases are particularly important or that > there aren't bugs in the current code; just that mixing up the > layers doesn't help ;-)
In practice no modules depend on firmware modules. :) I think we should take the approach of not clearing fp->file in unloadentry() however. That would result in correct behavior in every case I can think of (or as close to correct as you can get). In the above case the linker_file_unload() would have fail leaving the firmware module around. If you later kldunload'ed the other module, the firmware module would still be around and if a driver did another firmware_get/put sequence then the module would finally be unloaded on the second firmware_put(). However, that case will be much more rare than the current standalone firmware modules which can get into a funk where they can never be unloaded since the firmware(9) code would have leaked a reference (since it cleared fp->file just assuming that linker_file_unload() will work, but it might fail) and the user can't use kldunload to unload it even though the firmware isn't in use. -- John Baldwin <[EMAIL PROTECTED]> <>< http://www.FreeBSD.org/~jhb/ "Power Users Use the Power to Serve" = http://www.FreeBSD.org _______________________________________________ cvs-all@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/cvs-all To unsubscribe, send any mail to "[EMAIL PROTECTED]"
