Re: [RFC 01/20] iommu/iommufd: Add /dev/iommu core

Jason Gunthorpe via iommu
2021-10-15T11:18:14Z

On Fri, Oct 15, 2021 at 09:18:06AM +0000, Liu, Yi L wrote:

> > Acquire from the xarray is
> > rcu_lock()
> > ioas = xa_load()
> > if (ioas)
> > if (down_read_trylock(&ioas->destroying_lock))
>
> all good suggestions, will refine accordingly. Here destroying_lock is a
> rw_semaphore. right? Since down_read_trylock() accepts a rwsem.

Yes, you probably need a sleeping lock

Jason