From mboxrd@z Thu Jan 1 00:00:00 1970 From: Konrad Rzeszutek Wilk Subject: Re: [PATCH] qemu-xen-trad: free all the pirqs for msi/msix when driver unloads Date: Thu, 3 Jul 2014 13:54:15 -0400 Message-ID: <20140703175415.GB13710@konrad-lan.dumpdata.com> References: <1396975483-31442-1-git-send-email-konrad.wilk@oracle.com> <1396975483-31442-2-git-send-email-konrad.wilk@oracle.com> <21428.8198.371406.754367@mariner.uk.xensource.com> <53B4CA12.80709@oracle.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Received: from mail6.bemta14.messagelabs.com ([193.109.254.103]) by lists.xen.org with esmtp (Exim 4.72) (envelope-from ) id 1X2lDH-00078a-EM for xen-devel@lists.xenproject.org; Thu, 03 Jul 2014 17:54:27 +0000 Content-Disposition: inline In-Reply-To: <53B4CA12.80709@oracle.com> List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xen.org Errors-To: xen-devel-bounces@lists.xen.org To: Zhenzhong Duan Cc: xen-devel@lists.xenproject.org, Ian Jackson , stefano.stabellini@eu.citrix.com List-Id: xen-devel@lists.xenproject.org On Thu, Jul 03, 2014 at 11:12:18AM +0800, Zhenzhong Duan wrote: > There is a patch dependency missed. Is that one upstream as well? Or does it not need to be? If it is upstream, what is the title/commit id of that one? Thank you! > > commit adf74189dd58014744a4b8c9d64407d629da5e2f > Author: Stefano Stabellini > Date: Mon Dec 10 12:43:33 2012 +0000 > > qemu-xen-trad/pt_msi_disable: do not clear all MSI flags > > "qemu-xen-trad: fix msi_translate with PV event delivery" added a > pt_msi_disable() call into pt_msgctrl_reg_write, clearing the MSI flags > as a consequence. MSIs get enabled again soon after by calling > pt_msi_setup. > > However the MSI flags are only setup once in the pt_msgctrl_reg_init > function, so from the QEMU point of view the device has lost some > important properties, like for example PCI_MSI_FLAGS_64BIT. > > This patch fixes the bug by clearing only the MSI > enabled/mapped/initialized flags in pt_msi_disable. > > Signed-off-by: Stefano Stabellini > Tested-by: G.R. > Xen-devel: http://marc.info/?l=xen-devel&m=135489879503075 > > diff --git a/hw/pt-msi.c b/hw/pt-msi.c > index 73f737d..b03b989 100644 > --- a/hw/pt-msi.c > +++ b/hw/pt-msi.c > @@ -213,7 +213,7 @@ void pt_msi_disable(struct pt_dev *dev) > > out: > /* clear msi info */ > - dev->msi->flags = 0; > + dev->msi->flags &= ~(MSI_FLAG_UNINIT | PT_MSI_MAPPED | > PCI_MSI_FLAGS_ENABLE); > dev->msi->pirq = -1; > dev->msi_trans_en = 0; > } > > On 2014-7-2 23:06, Ian Jackson wrote: > >Konrad Rzeszutek Wilk writes ("[Xen-devel] [PATCH] qemu-xen-trad: free all the pirqs for msi/msix when driver unloads"): > >>From: Zhenzhong Duan > >> > >>Pirqs are not freed when driver unloads, then new pirqs are allocated when > >>driver reloads. This could exhaust pirqs if do it in a loop. > >> > >>This patch fixes the bug by freeing pirqs when ENABLE bit is cleared in > >>msi/msix control reg. > >I have backported this to 4.4 and 4.3. It did not apply cleanly to > >4.2 (and I have not investgated why). > > > >Thanks, > >Ian. >