Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S938613AbcKKVOi (ORCPT ); Fri, 11 Nov 2016 16:14:38 -0500 Received: from mail.kernel.org ([198.145.29.136]:35796 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S935582AbcKKVOh (ORCPT ); Fri, 11 Nov 2016 16:14:37 -0500 Date: Fri, 11 Nov 2016 15:03:59 -0600 From: Bjorn Helgaas To: Long Li Cc: "K. Y. Srinivasan" , Haiyang Zhang , Bjorn Helgaas , devel@linuxdriverproject.org, linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org, Long Li Subject: Re: [PATCH 1/2 v3] pci-hyperv: properly handle pci bus remove Message-ID: <20161111210359.GD9868@bhelgaas-glaptop.roam.corp.google.com> References: <1475563367-16511-1-git-send-email-longli@exchange.microsoft.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1475563367-16511-1-git-send-email-longli@exchange.microsoft.com> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2914 Lines: 84 On Mon, Oct 03, 2016 at 11:42:47PM -0700, Long Li wrote: > From: Long Li > > hv_pci_devices_present is called in hv_pci_remove when we remove a PCI device from host (e.g. by disabling SRIOV on a device). In hv_pci_remove, the bus is already removed before the call, so we don't need to rescan the bus in the workqueue scheduled from hv_pci_devices_present. By introducing status hv_pcibus_removed, we can avoid this situation. > > Signed-off-by: Long Li > Tested-by: Cathy Avery > Reported-by: Xiaofeng Wang I need an ack from the Hyper-V maintainers. I see acks for previous versions, but I don't know whether you've changed things that would invalidate those acks. If the acks still apply, please include them and repost these patches. Also, please run "git log --oneline drivers/pci/host/pci-hyperv.c" and make your subject line match the previous ones. > --- > drivers/pci/host/pci-hyperv.c | 20 +++++++++++++++++--- > 1 file changed, 17 insertions(+), 3 deletions(-) > > diff --git a/drivers/pci/host/pci-hyperv.c b/drivers/pci/host/pci-hyperv.c > index a8deeca..4a37598 100644 > --- a/drivers/pci/host/pci-hyperv.c > +++ b/drivers/pci/host/pci-hyperv.c > @@ -348,6 +348,7 @@ enum hv_pcibus_state { > hv_pcibus_init = 0, > hv_pcibus_probed, > hv_pcibus_installed, > + hv_pcibus_removed, > hv_pcibus_maximum > }; > > @@ -1481,13 +1482,24 @@ static void pci_devices_present_work(struct work_struct *work) > put_pcichild(hpdev, hv_pcidev_ref_initial); > } > > - /* Tell the core to rescan bus because there may have been changes. */ > - if (hbus->state == hv_pcibus_installed) { > + switch (hbus->state) { > + case hv_pcibus_installed: > + /* > + * Tell the core to rescan bus > + * because there may have been changes. > + */ > pci_lock_rescan_remove(); > pci_scan_child_bus(hbus->pci_bus); > pci_unlock_rescan_remove(); > - } else { > + break; > + > + case hv_pcibus_init: > + case hv_pcibus_probed: > survey_child_resources(hbus); > + break; > + > + default: > + break; > } > > up(&hbus->enum_sem); > @@ -2163,6 +2175,7 @@ static int hv_pci_probe(struct hv_device *hdev, > hbus = kzalloc(sizeof(*hbus), GFP_KERNEL); > if (!hbus) > return -ENOMEM; > + hbus->state = hv_pcibus_init; > > /* > * The PCI bus "domain" is what is called "segment" in ACPI and > @@ -2305,6 +2318,7 @@ static int hv_pci_remove(struct hv_device *hdev) > pci_stop_root_bus(hbus->pci_bus); > pci_remove_root_bus(hbus->pci_bus); > pci_unlock_rescan_remove(); > + hbus->state = hv_pcibus_removed; > } > > ret = hv_send_resources_released(hdev); > -- > 1.8.5.6 > > -- > To unsubscribe from this list: send the line "unsubscribe linux-pci" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html