From mboxrd@z Thu Jan 1 00:00:00 1970 From: Zhenzhong Duan Subject: Re: [PATCH] qemu-xen-trad: free all the pirqs for msi/msix when driver unloads Date: Tue, 08 Jul 2014 09:12:39 +0800 Message-ID: <53BB4587.2050106@oracle.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> <20140703175415.GB13710@konrad-lan.dumpdata.com> <53B60382.2070506@oracle.com> <20140707204010.GA17821@laptop.dumpdata.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii"; Format="flowed" Content-Transfer-Encoding: 7bit Return-path: Received: from mail6.bemta4.messagelabs.com ([85.158.143.247]) by lists.xen.org with esmtp (Exim 4.72) (envelope-from ) id 1X4Jxg-0003X2-BF for xen-devel@lists.xenproject.org; Tue, 08 Jul 2014 01:12:48 +0000 In-Reply-To: <20140707204010.GA17821@laptop.dumpdata.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: Konrad Rzeszutek Wilk Cc: xen-devel@lists.xenproject.org, Ian Jackson , stefano.stabellini@eu.citrix.com List-Id: xen-devel@lists.xenproject.org On 2014-7-8 4:40, Konrad Rzeszutek Wilk wrote: > On Fri, Jul 04, 2014 at 09:29:38AM +0800, Zhenzhong Duan wrote: >> On 2014-7-4 1:54, Konrad Rzeszutek Wilk wrote: >>> 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! >> It's upstream, see detail below > > [konrad@build-external qemu-xen-dir]$ pwd > /home/konrad/xtt-x86_64/xen/tools/qemu-xen-dir > [konrad@build-external qemu-xen-dir]$ git show adf74189dd58014744a4b8c9d64407d629da5e2f > fatal: bad object adf74189dd58014744a4b8c9d64407d629da5e2f > [konrad@build-external qemu-xen-dir]$ git log --grep="clear all MSI" > [konrad@build-external qemu-xen-dir]$ > > ? Sorry, I mean qemu-xen-traditional upstream git zduan >>>> 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.