David
I am having trouble getting the reference to "drm_global_mutex" to link correctly in drm/udl. The error is
ERROR: "drm_global_mutex" [drivers/gpu/drm/udl/udl.ko] undefined! make[1]: *** [__modpost] Error 1 make: *** [modules] Error 2
This seems to be only accessed in the common drm code. Do you have a suggestion how to get around it?
On Wed, Feb 10, 2016 at 1:35 PM, David Herrmann dh.herrmann@gmail.com wrote:
Hi
On Wed, Feb 10, 2016 at 9:51 PM, Haixia Shi hshi@chromium.org wrote:
This should rather be:
drm_release(inode, filp); mutex_lock(&drm_global_mutex); if (!dev->open_count && udl_device_is_unplugged(dev)) drm_put_dev(dev); mutex_unlock(&drm_global_mutex); return 0;There is no reason to look at the return code of drm_release(), ever.
But drm_release() does return a retcode. It would still make sense to
return
that as-is in case any existing code relies on it.
Nobody should ever return error codes from fops.release(). It is completely bogus. You rather confuse generic user-space that calls close(), than getting any benefit out of it.
But TBH, I don't care. Feel free to forward the return value. But still, please change the order of the calls as I did.
Thanks David