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Date:   Mon, 28 Jan 2019 05:42:42 -0800
From:   Christoph Hellwig <hch@infradead.org>
To:     Jason Gunthorpe <jgg@mellanox.com>
Cc:     "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        NeilBrown <neilb@suse.com>, Jiri Kosina <trivial@kernel.org>
Subject: Re: [PATCH trivial] kernel.h: Make container_of_safe type safe
Message-ID: <20190128134242.GA10951@infradead.org>
References: <20190124205451.GA19634@ziepe.ca>
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On Thu, Jan 24, 2019 at 08:55:05PM +0000, Jason Gunthorpe wrote:
> The final ternary expression is given void * and type * as arguments, so
> the resulting type of the macro ends up being void *.
> 
> container_of returns a type which maches the argument, this provides type
> safety and allows the expression to be immediately used as the target
> type.
> 
> Explicitly cast ERR_CAST() to get the correct type.

I think we should just kill off container_of_safe - it has no user
in the tree, is grossly misnamed and not really all that useful to start
with.