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From: Greg Thelen <gthelen@google.com>
To: Rafael Aquini <aquini@redhat.com>
Cc: linux-kernel@vger.kernel.org, Andrew Morton <akpm@linux-foundation.org>,
        Davidlohr Bueso <davidlohr@hp.com>, Rik van Riel <riel@redhat.com>
Subject: Re: [PATCH] ipc: introduce ipc_valid_object() helper to sort out IPC_RMID races
References: <e70c06876f986f0ac7f2f104bab50edff4a524a0.1387302999.git.aquini@redhat.com>
Date: Tue, 17 Dec 2013 12:41:46 -0800
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On Tue, Dec 17 2013, Rafael Aquini wrote:

> After the locking semantics for the SysV IPC API got improved, a couple of
> IPC_RMID race windows were opened because we ended up dropping the
> 'kern_ipc_perm.deleted' check performed way down in ipc_lock().
> The spotted races got sorted out by re-introducing the old test within
> the racy critical sections.
>
> This patch introduces ipc_valid_object() to consolidate the way we cope with
> IPC_RMID races by using the same abstraction across the API implementation.
>
> Signed-off-by: Rafael Aquini <aquini@redhat.com>

Acked-by: Greg Thelen <gthelen@google.com>