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Date: Fri, 25 Apr 2025 20:36:14 +0200
From: Christoph Hellwig <hch@lst.de>
To: Ming Lei <ming.lei@redhat.com>
Cc: Jens Axboe <axboe@kernel.dk>, linux-block@vger.kernel.org,
	Nilay Shroff <nilay@linux.ibm.com>,
	Shinichiro Kawasaki <shinichiro.kawasaki@wdc.com>,
	Thomas =?iso-8859-1?Q?Hellstr=F6m?= <thomas.hellstrom@linux.intel.com>,
	Christoph Hellwig <hch@lst.de>
Subject: Re: [PATCH V3 15/20] block: fail to show/store elevator sysfs
 attribute if elevator is dying
Message-ID: <20250425183614.GA26393@lst.de>
References: <20250424152148.1066220-1-ming.lei@redhat.com> <20250424152148.1066220-16-ming.lei@redhat.com>
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User-Agent: Mutt/1.5.17 (2007-11-01)

On Thu, Apr 24, 2025 at 11:21:38PM +0800, Ming Lei wrote:
> +	if (test_bit(ELEVATOR_FLAG_DYING, &e->flags))
> +		error = -ENODEV;
> +	else
> +		error = e->type ? entry->show(e, page) : -ENOENT;

Weird style mix, I'd expand the check for ->type to a proper else
if here as well.  But how can e->type actually be NULL here to start
with?