Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756905AbaGNTBl (ORCPT ); Mon, 14 Jul 2014 15:01:41 -0400 Received: from vserver.eikelenboom.it ([84.200.39.61]:50178 "EHLO smtp.eikelenboom.it" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756835AbaGNTBe (ORCPT ); Mon, 14 Jul 2014 15:01:34 -0400 Date: Mon, 14 Jul 2014 21:01:29 +0200 From: Sander Eikelenboom Organization: Eikelenboom IT services X-Priority: 3 (Normal) Message-ID: <1499016487.20140714210129@eikelenboom.it> To: Konrad Rzeszutek Wilk CC: konrad@kernel.org, xen-devel@lists.xenproject.org, , , Subject: Re: [Xen-devel] [PATCH v4] PCI back fixes for 3.17. In-Reply-To: <20140714184547.GA18896@laptop.dumpdata.com> References: <1405109332-31659-1-git-send-email-konrad@kernel.org> <768165707.20140714183755@eikelenboom.it> <20140714172225.GA10497@laptop.dumpdata.com> <652296445.20140714192923@eikelenboom.it> <20140714173753.GB12920@laptop.dumpdata.com> <9210423415.20140714194304@eikelenboom.it> <20140714174525.GD12920@laptop.dumpdata.com> <1332864311.20140714202433@eikelenboom.it> <20140714184547.GA18896@laptop.dumpdata.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Monday, July 14, 2014, 8:45:47 PM, you wrote: > On Mon, Jul 14, 2014 at 08:24:33PM +0200, Sander Eikelenboom wrote: >> >> Monday, July 14, 2014, 7:45:25 PM, you wrote: >> >> > On Mon, Jul 14, 2014 at 07:43:04PM +0200, Sander Eikelenboom wrote: >> >> >> >> Monday, July 14, 2014, 7:37:53 PM, you wrote: >> >> >> >> >> >> Ad B) >> >> >> >> >> >> >> >> root@dom0:~# xl pci-list router >> >> >> >> Vdev Device >> >> >> >> 05.0 0000:00:1b.0 >> >> >> >> >> >> >> >> root@dom0:~# xl pci-assignable-list >> >> >> >> 0000:02:00.0 >> >> >> >> >> >> >> >> root@dom0:~# xl pci-detach router 00:1b.0 >> >> >> >> dmesg shows: >> >> >> >> [ 199.742668] pciback 0000:00:1b.0: restoring config space at offset 0x10 (was 0x4, writing 0xf7d30004) >> >> >> >> [ 199.743527] pciback 0000:00:1b.0: restoring config space at offset 0xc (was 0x0, writing 0x10) >> >> >> >> [ 199.744321] pciback 0000:00:1b.0: restoring config space at offset 0x4 (was 0x100000, writing 0x100006) >> >> >> >> [ 199.757184] xen-pciback pci-1-0: xen_pcibk_xenbus_remove freeing pdev @ 0xffff8800589fce40 >> >> >> >> [ 199.758139] xen-pciback pci-1-0: xen_pcibk_disconnect pdev @ 0xffff8800589fce40 >> >> >> >> [ 199.862595] xen: xen_unregister_device_domain_owner >> >> >> >> >> >> >> >> xl dmesg shows: >> >> >> >> (XEN) [2014-07-14 16:28:29] memory_map:remove: dom1 gfn=f3070 mfn=f7d30 nr=4 >> >> >> >> (XEN) [2014-07-14 16:28:29] io.c:322: d1: unbind: m_gsi=22 g_gsi=36 dev=00:00.5 intx=0 >> >> >> >> (XEN) [2014-07-14 16:28:29] io.c:390: d1 unmap: m_irq=22 dev=00:00.5 intx=0 >> >> >> >> (XEN) [2014-07-14 16:28:29] [VT-D]iommu.c:1579: d1:PCIe: unmap 0000:00:1b.0 >> >> >> >> (XEN) [2014-07-14 16:28:29] [VT-D]iommu.c:1440: d0:PCIe: map 0000:00:1b.0 >> >> >> >> >> >> >> >> root@dom0:~# xl pci-list router >> >> >> >> root@dom0:~# xl pci-assignable-list >> >> >> >> 0000:00:1b.0 >> >> >> >> 0000:02:00.0 >> >> >> >> >> >> >> >> root@dom0:~# xl pci-assignable-remove 00:1b.0 >> >> >> >> dmesg shows: >> >> >> >> [ 318.827415] xen: xen_unregister_device_domain_owner >> >> >> >> [ 318.828771] xen: xen_unregister_device_domain_owner: ENODEV >> >> >> >> [ 318.930869] pciback 0000:00:1b.0: restoring config space at offset 0x10 (was 0x4, writing 0xf7d30004) >> >> >> >> [ 318.933435] pciback 0000:00:1b.0: restoring config space at offset 0xc (was 0x0, writing 0x10) >> >> >> >> [ 318.935877] pciback 0000:00:1b.0: restoring config space at offset 0x4 (was 0x100000, writing 0x100006) >> >> >> >> >> >> >> >> root@dom0:~# xl pci-list router >> >> >> >> root@dom0:~# xl pci-assignable-list >> >> >> >> 0000:02:00.0 >> >> >> >> >> >> >> >> >> >> >> >> >> >> > And if you do: >> >> >> >> >> >> > # xl pci-detach router 02:00.0 >> >> >> >> >> >> >> > Err, I meant >> >> > # xl pci-assignable-remove 02:00.0 >> >> >> >> Ah ok .. so that is: >> >> remove a device from pciback that has never been assigned to any guest .. >> >> >> >> will also give that a go .. although that probably won't be a problem. >> >> > Right. So I think it all works as expected? That is if you have >> > two PCI devices assigned to a guest and want to re-use them you >> > have to do the 'pci-detach' twice and then follow that with >> > 'pci-assignable-remove' twice as well? >> >> Well except that's not what i want :-) .. that's about the same as shutting down >> the guest .. and indeed that works :-) >> >> What i want to do is to remove just *one* device and leave the other one in the guest. >> >> The one that i remove .. i would like to be able to remove it from being >> assignable .. (rebind it in dom0) and/or assign it to another guest. > Aha >> >> And that fails because pciback still thinks the guest owns the device .. >> while libxl thinks it doesn't (outcome of xl pci-assignable-list). > Oh >> >> When doing the: >> >> # xl pci-assignable-list >> 0000:02:00.0 >> # xl pci-assignable-remove 02:00.0 >> dmesg shows: >> [ 443.292951] xen: xen_unregister_device_domain_owner >> [ 443.294308] xen: xen_unregister_device_domain_owner: ENODEV >> [ 443.398827] pciback 0000:02:00.0: restoring config space at offset 0x3c (was 0x100, writing 0x104) >> [ 443.400797] pciback 0000:02:00.0: restoring config space at offset 0x10 (was 0x4, writing 0xf7c00004) >> [ 443.401713] pciback 0000:02:00.0: restoring config space at offset 0x4 (was 0x100000, writing 0x100006) >> >> which i think is what is expected .. > Right. >> >> >> Hmm /sys/bus/pci/drivers/pciback doesn't shed much light, because in the state >> just after a xl pci-detach, the device is still registred by pciback (from dom0's >> view) which is correct, what is wrong is that pciback still seems to think that >> it is in turn still owned by the guest. That doesn't get reflected in the info >> available in the /sys dir. > Oh >> >> Ok over to xen-store ... > I think I had a patch for that in libxl. It was the order of operations it was > doing - it did the 'unbind' first and then it did the XenBus operations. >> >> first a diff between the booted guest with two devices passed through and the >> state after the "xl pci-detach router 00:1b.0" >> >> root@creanuc:~# diff -U10 xs-before-detach-first.txt xs-after-detach-first.txt >> --- xs-before-detach-first.txt 2014-07-14 19:56:23.233576000 +0200 >> +++ xs-after-detach-first.txt 2014-07-14 20:00:00.053576000 +0200 >> @@ -185,35 +185,29 @@ >> feature-rx-flip = "0" >> feature-split-event-channels = "1" >> multi-queue-max-queues = "4" >> hotplug-status = "connected" >> pci = "" >> 1 = "" >> 0 = "" >> frontend = "/local/domain/1/device/pci/0" >> frontend-id = "1" >> online = "1" >> - state = "3" >> + state = "7" >> domain = "router" >> key-0 = "0000:02:00.0" >> dev-0 = "0000:02:00.0" >> vdevfn-0 = "28" >> opts-0 = "msitranslate=0,power_mgmt=0,permissive=0" >> state-0 = "3" >> - key-1 = "0000:00:1b.0" >> - dev-1 = "0000:00:1b.0" >> - vdevfn-1 = "30" >> - opts-1 = "msitranslate=0,power_mgmt=0,permissive=0" >> - state-1 = "3" >> - num_devs = "2" >> + num_devs = "1" >> vdev-0 = "0000:00:00.00" >> - vdev-1 = "0000:00:01.00" >> root-0 = "0000:00" >> root_num = "1" >> 1 = "" >> vm = "/vm/a102d97e-8388-414e-97e5-cc394656c47d" >> name = "router" >> cpu = "" >> 0 = "" >> availability = "online" >> 1 = "" >> availability = "online" >> >> It seems ok, perhaps apart from the general pci state going from 3 to 7 ? >> Haven't looked up the exact states, but since only one domain is removes i would >> still expect it to be 3 ? > 7 is Reconfiguring which is what it should move to (to update the XenBus). Ok, but that should than be acknowledged somewhere by someone i suppose .. and not stay in that state ? >> >> >> Now a diff before and after the "xl pci-assignable-remove 00:1b.0" >> diff xs-after-detach-first.txt xs-after-pci-assignable-remove-first.txt is >> empty, as expected since this is a pciback only thing now involving any guest. >> >> >> And now the last diff, between the state before and after the "xl pci-detach >> 02:00.0" removing the last pci device from the guest. >> >> root@creanuc:~# diff -U5 xs-after-pci-assignable-remove-first.txt xs-after-pci-detach-second.txt >> --- xs-after-pci-assignable-remove-first.txt 2014-07-14 20:00:45.161576000 +0200 >> +++ xs-after-pci-detach-second.txt 2014-07-14 20:01:20.177576000 +0200 >> @@ -184,27 +184,10 @@ >> feature-rx-copy = "1" >> feature-rx-flip = "0" >> feature-split-event-channels = "1" >> multi-queue-max-queues = "4" >> hotplug-status = "connected" >> - pci = "" >> - 1 = "" >> - 0 = "" >> - frontend = "/local/domain/1/device/pci/0" >> - frontend-id = "1" >> - online = "1" >> - state = "7" >> - domain = "router" >> - key-0 = "0000:02:00.0" >> - dev-0 = "0000:02:00.0" >> - vdevfn-0 = "28" >> - opts-0 = "msitranslate=0,power_mgmt=0,permissive=0" >> - state-0 = "3" >> - num_devs = "1" >> - vdev-0 = "0000:00:00.00" >> - root-0 = "0000:00" >> - root_num = "1" >> 1 = "" >> vm = "/vm/a102d97e-8388-414e-97e5-cc394656c47d" >> name = "router" >> cpu = "" >> 0 = "" >> @@ -249,15 +232,10 @@ >> event-channel-rx = "25" >> request-rx-copy = "1" >> feature-rx-notify = "1" >> feature-sg = "1" >> feature-gso-tcpv4 = "1" >> - pci = "" >> - 0 = "" >> - backend = "/local/domain/0/backend/pci/1/0" >> - backend-id = "0" >> - state = "1" >> control = "" >> shutdown = "" >> platform-feature-multiprocessor-suspend = "1" >> platform-feature-xs_reset_watches = "1" >> hvmloader = "" >> >> That seems ok. >> >> So apart from that perhaps incorrect general pci state change, the info in >> xenstore seems to be OK. >> >> So it does seem to be a lack of pciback receiving a confirm from libxl / qemu that the >> device is indeed removed from the guest for the final deregistring of the >> ownership. >> >> Because after a pci-detach the pci device is: >> - removed from xen-store as attached to the guest >> - the iommu has assigned/mapped it back to dom0 >> - xl pci-assignable-list shows it as assignable again >> >> So only pciback is the only one left out of the party :-) >> Couldn't it be somehow tied to the iommu events, since it should be in sync with that i suppose ? > Let me find out what is up with this. Once the device > is de-assigned from a guest (even if forcefully) it should > be possible to assign it to another. Yes .. at least for the rebinding to dom0 case, because the pci-assignable-remove seems to do it forcefully now. But i haven't tried what it does when reassigning to another guest (if it forcefully swaps ownership then, since the pci-assignable-remove isn't involved then). Will give the xen patch a try. >> >> -- >> Sander >> >> BTW, i don't see the "do_flr" anywhere in /sys/*/pciback/ ? > We been having a lengthy discussion about this and David is out > on vacation so will have to wait until he is back. >> -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/