From mboxrd@z Thu Jan  1 00:00:00 1970
Return-Path: <owner-linux-mm@kvack.org>
Date: Tue, 10 Apr 2018 09:00:19 -0400
From: Johannes Weiner <hannes@cmpxchg.org>
To: Matthew Wilcox <willy@infradead.org>
Cc: linux-mm@kvack.org, Matthew Wilcox <mawilcox@microsoft.com>,
	Christoph Lameter <cl@linux.com>, Pekka Enberg <penberg@kernel.org>,
	David Rientjes <rientjes@google.com>,
	Joonsoo Kim <iamjoonsoo.kim@lge.com>,
	Andrew Morton <akpm@linux-foundation.org>,
	linux-kernel@vger.kernel.org, Jan Kara <jack@suse.cz>,
	Jeff Layton <jlayton@redhat.com>,
	Mel Gorman <mgorman@techsingularity.net>, stable@vger.kernel.org
Subject: Re: [PATCH 1/2] slab: __GFP_ZERO is incompatible with a constructor
Message-ID: <20180410130019.GA7010@cmpxchg.org>
References: <20180410125351.15837-1-willy@infradead.org>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <20180410125351.15837-1-willy@infradead.org>
Sender: owner-linux-mm@kvack.org
List-ID: <stable.vger.kernel.org>

On Tue, Apr 10, 2018 at 05:53:50AM -0700, Matthew Wilcox wrote:
> From: Matthew Wilcox <mawilcox@microsoft.com>
> 
> __GFP_ZERO requests that the object be initialised to all-zeroes,
> while the purpose of a constructor is to initialise an object to a
> particular pattern.  We cannot do both.  Add a warning to catch any
> users who mistakenly pass a __GFP_ZERO flag when allocating a slab with
> a constructor.
> 
> Fixes: d07dbea46405 ("Slab allocators: support __GFP_ZERO in all allocators")
> Signed-off-by: Matthew Wilcox <mawilcox@microsoft.com>
> Cc: stable@vger.kernel.org

Acked-by: Johannes Weiner <hannes@cmpxchg.org>