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Date:   Thu, 21 Sep 2023 11:27:16 +0300
From:   Leon Romanovsky <leon@kernel.org>
To:     Jason Gunthorpe <jgg@nvidia.com>
Cc:     Shay Drory <shayd@nvidia.com>, linux-rdma@vger.kernel.org,
        Michael Guralnik <michaelgur@nvidia.com>
Subject: Re: [PATCH rdma-rc] RDMA/mlx5: Fix mkey cache possible deadlock on
 cleanup
Message-ID: <20230921082716.GC1642130@unreal>
References: <2c0452d944a865b060709af71940dafc4aad8b89.1695203715.git.leon@kernel.org>
 <20230920140112.GB13733@nvidia.com>
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On Wed, Sep 20, 2023 at 11:01:12AM -0300, Jason Gunthorpe wrote:
> On Wed, Sep 20, 2023 at 12:56:18PM +0300, Leon Romanovsky wrote:
> > @@ -1796,6 +1804,10 @@ static int cache_ent_find_and_store(struct mlx5_ib_dev *dev,
> >  	}
> >  
> >  	mutex_lock(&cache->rb_lock);
> > +	if (cache->disable) {
> > +		mutex_unlock(&cache->rb_lock);
> > +		return 0;
> > +	}
> 
> 
> I don't get this.
> 
> Shouldn't we just initialize the ent->disabled to cache->disabled if
> we happen to be creating a new ent?

I'm convinced that new entries can't be created when we are calling to
mlx5_mkey_cache_cleanup().

Thanks

> 
> Jason
>