From: Cong Wang <[email protected]>
Date: Wed, 5 Jul 2017 13:50:00 -0700
> We are not allowed to block on the RCU reader side, so can't
> just hold the mutex as before. As a quick fix, convert it to
> a spinlock.
>
> Fixes: d9f1f61c0801 ("tap: Extending tap device create/destroy APIs")
> Reported-by: Christian Borntraeger <[email protected]>
> Cc: Sainath Grandhi <[email protected]>
> Signed-off-by: Cong Wang <[email protected]>
I agree with Eric that we should use idr_preload() and
idr_preload_end() here so that we can still use GFP_KERNEL even though
we're now using a spinlock instead of a mutex.
