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Date: Fri, 2 Jan 2015 17:34:47 +0000
From: Al Viro <viro@ZenIV.linux.org.uk>
To: Jens Axboe <axboe@fb.com>
Cc: Ming Lei <ming.lei@canonical.com>, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] block: fix checking return value of blk_mq_init_queue
Message-ID: <20150102173447.GS22149@ZenIV.linux.org.uk>
References: <1420208727-9563-1-git-send-email-ming.lei@canonical.com>
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On Fri, Jan 02, 2015 at 08:53:11AM -0700, Jens Axboe wrote:
> On 01/02/2015 07:25 AM, Ming Lei wrote:
> >Check IS_ERR_OR_NULL(return value) instead of just return value.
> 
> Thanks Ming, applied.

Umm...  Looking at the callers, I'd suggest making it _never_ return NULL -
it's always treates as ERR_PTR(-ENOMEM) anyway.  Then the checks would be
just IS_ERR(...).

IS_ERR_OR_NULL() is very often a sign of lousy calling conventions and
this case is no exception...