From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from out4-smtp.messagingengine.com ([66.111.4.28]:33965 "EHLO out4-smtp.messagingengine.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752138AbdJ0QxM (ORCPT ); Fri, 27 Oct 2017 12:53:12 -0400 Date: Fri, 27 Oct 2017 18:53:16 +0200 From: Greg KH To: Anisse Astier Cc: stable@vger.kernel.org, Sasha Levin , Miklos Szeredi , linux-unionfs@vger.kernel.org Subject: Re: ca4c8a3a800039 ovl: treat special files like a regular fs Message-ID: <20171027165316.GA21090@kroah.com> References: <20171027152048.GA1246@bifrost> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20171027152048.GA1246@bifrost> Sender: stable-owner@vger.kernel.org List-ID: On Fri, Oct 27, 2017 at 05:20:48PM +0200, Anisse Astier wrote: > Hi, > > Would it be possible to backport upstream commit > ca4c8a3a800039c2681d609c5b7491c1bd17c0a7 into 4.9 ? > > From: Miklos Szeredi > ovl: treat special files like a regular fs > > No sense in opening special files on the underlying layers, they work just > as well if opened on the overlay. > > Side effect is that it's no longer possible to connect one side of a pipe > opened on overlayfs with the other side opened on the underlying layer. > > > Before this it's impossible to do in-kernel resolution of a device file, > for example to mount or use dmsetup. So, this adds a new feature, and does not fix a bug, right? :) > Miklos, you say this might cause a behaviour change in a very > particular case; but did it cause an issue upstream since it was merged > in 4.10 ? > > I also wish this was fixed in 4.1, so I did a tentative backport below. > What do you think Sasha, Miklos ? What is preventing you from using a newer kernel like 4.13 if you rely on this new feature? thanks, greg k-h