From mboxrd@z Thu Jan 1 00:00:00 1970 From: Greg KH Subject: Re: [[PATCH stable <3.12]] xen-netback: fix refcnt unbalance for 3.11 and earlier versions Date: Mon, 2 Dec 2013 09:19:58 -0800 Message-ID: <20131202171958.GA661@kroah.com> References: <1385642889-11513-1-git-send-email-wei.liu2@citrix.com> <20131201044835.GB19516@kroah.com> <20131202120134.GA14293@zion.uk.xensource.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: xen-devel@lists.xen.org, netdev@vger.kernel.org, stable@vger.kernel.org, tomasz.wroblewski@citrix.com, Ian Campbell , Konrad Wilk , David Vrabel To: Wei Liu Return-path: Content-Disposition: inline In-Reply-To: <20131202120134.GA14293@zion.uk.xensource.com> Sender: stable-owner@vger.kernel.org List-Id: netdev.vger.kernel.org On Mon, Dec 02, 2013 at 12:01:34PM +0000, Wei Liu wrote: > On Sat, Nov 30, 2013 at 08:48:35PM -0800, Greg KH wrote: > > On Thu, Nov 28, 2013 at 12:48:09PM +0000, Wei Liu wrote: > > > With the introduction of "xen-netback: Don't destroy the netdev until > > > the vif is shut down" (upstream commit id 279f438e36), vif disconnect > > > and free are separated. However in the backported verion reference > > > counting code was not correctly modified, and the reset of vif->tx_irq > > > was lost. If frontend goes through vif life cycle more than once the > > > reference counting is skewed. > > > > > > This patch adds back the missing tx_irq reset line. It also moves > > > several lines of the reference counting code to vif_free, so the moved > > > code corresponds to the counterpart in vif_alloc, thus the reference > > > counting is balanced. > > > > > > 3.12 and onward versions are not affected by this bug, because reference > > > counting code was removed due to the introduction of 1:1 model. > > > > > > This pacth should be backported to all stable verions which are lower > > > than 3.12 and have 279f438e36. > > > > What stable versions are those? 279f438e36 showed up in 3.12-rc2, and > > was not marked for stable inclusion, so what kernel would end up needing > > this patch? > > > > Greg, > > 279f438e36 was backported to at least stable branches > > 3.11.y: <13826815042174@kroah.org> commit id f495ddc46 > 3.10.y: <13828112161592@kroah.com> commit id a4626bf64 > > So at least those two need this patch. > > And I remeber 3.8.y.z extended stable branch maintained by Kamal also > has the said commit. > > > confused, > > > > Sorry, I should've stated cleared all versions. > > BTW the above patch applies to 3.11.y. I can provide backports to 3.10.y > as well, if necessary. As 3.11.y is now dead, there's not much I can do with that one, but I could use a backport for 3.10.y, as this patch does not apply there, thanks. greg k-h