Messages in this thread | | | Date | Sat, 8 Nov 2014 11:06:55 -0800 | From | Greg Kroah-Hartman <> | Subject | Re: [PATCH v2 1/3] firmware loader: Introduce new API - request_firmware_abort() |
| |
On Mon, Nov 03, 2014 at 11:07:08AM +0800, Kweh Hock Leong wrote: > From: "Kweh, Hock Leong" <hock.leong.kweh@intel.com> > > Besides aborting through user helper interface, a new API > request_firmware_abort() allows kernel driver module to abort the > request_firmware() / request_firmware_nowait() when they are no > longer needed. It is useful for cancelling an outstanding firmware > load if initiated from inside a module where that module is in the > process of being unloaded, since the unload function may not have > a handle to the struct firmware_buf. > > Note for people who use request_firmware_nowait(): > You are required to do your own synchronization after you call > request_firmware_abort() in order to continue unloading the > module. The example synchronization code shows below: > > while (THIS_MODULE && module_refcount(THIS_MODULE)) > msleep(20);
As others have pointed out, this isn't ok, and is totally racy and should never end up in a driver. Never mess with THIS_MODULE from within the same module, otherwise it's racy and broken code.
So can you please rework this to not require this?
thanks,
greg k-h
| |