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Date: Wed, 7 Oct 2026 17:28:11 +0200
From: Christoph Hellwig <hch@lst.de>
To: Damien Le Moal <dlemoal@kernel.org>
Cc: Christoph Hellwig <hch@lst.de>, Jens Axboe <axboe@kernel.dk>,
	linux-block@vger.kernel.org, linux-scsi@vger.kernel.org,
	"Martin K . Petersen" <martin.petersen@oracle.com>
Subject: Re: [PATCH v3 3/7] block: add storage element management ioctls
Message-ID: <20261007152811.GA8435@lst.de>
References: <20261007082344.1049179-1-dlemoal@kernel.org> <20261007082344.1049179-4-dlemoal@kernel.org> <20261007133922.GC31906@lst.de> <e11de48b-e719-4cfc-a08d-916a8603782d@kernel.org>
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On Wed, Oct 07, 2026 at 04:37:49PM +0200, Damien Le Moal wrote:
> >> +	elements = kzalloc_objs(struct blk_storage_element, nr_elements);
> > 
> > This doesn't work as it could race.  We'll always need to allocate
> > the space for all the elements the user asked for?
> 
> I am not following... The number of elements of a drive never changes, and that
> is what nr_elements indicates. So getting the min with the user indicated value
> still gives all elements, and that also creates a bound in case we get a crazy
> large value from the user.

The explicitly pass the bound in.  Or have it struct gendisk as a
fixed value.