Pull assorted fixes - mostly vfs - from Al Viro:
"Assorted fixes, with an unexpected detour into vfio refcounting logics
(fell out when digging in an analog of eventpoll race in there)."
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
task_work: add a scheduling point in task_work_run()
fs: fix fs/namei.c kernel-doc warnings
eventpoll: use-after-possible-free in epoll_create1()
vfio: grab vfio_device reference *before* exposing the sucker via fd_install()
vfio: get rid of vfio_device_put()/vfio_group_get_device* races
vfio: get rid of open-coding kref_put_mutex
introduce kref_put_mutex()
vfio: don't dereference after kfree...
mqueue: lift mnt_want_write() outside ->i_mutex, clean up a bit
467e9e51d0