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Date:   Sat, 2 Jun 2018 00:59:03 +0800
From:   Herbert Xu <herbert@gondor.apana.org.au>
To:     Davidlohr Bueso <dave@stgolabs.net>
Cc:     akpm@linux-foundation.org, torvalds@linux-foundation.org,
        tgraf@suug.ch, manfred@colorfullife.com, mhocko@kernel.org,
        guillaume.knispel@supersonicimagine.com, linux-api@vger.kernel.org,
        linux-kernel@vger.kernel.org, Davidlohr Bueso <dbueso@suse.de>
Subject: Re: [PATCH 1/5] lib/rhashtable: convert param sanitations to WARN_ON
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On Fri, Jun 01, 2018 at 09:53:47AM -0700, Davidlohr Bueso wrote:
>
> Curious, are these users setting up the param structure dynamically
> or something that they can pass along bogus values?
> 
> If that's the case then yes, I definitely agree.

It's just a quality of implementation issue.  This is a generic API.
Sure for early-boot users like yours it makes sense to just WARN_ON
rather than deal with the messy hash table allocation failure.

But for a driver author writing some kernel module it isn't nice
to WARN_ON and then crash on a NULL-pointer dereference when we
can cleanly fail the table init.

Cheers,
-- 
Email: Herbert Xu <herbert@gondor.apana.org.au>
Home Page: http://gondor.apana.org.au/~herbert/
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