From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([208.118.235.92]:38827) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1SSWrq-0008UN-J6 for qemu-devel@nongnu.org; Thu, 10 May 2012 13:09:32 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1SSWrk-0003ta-VO for qemu-devel@nongnu.org; Thu, 10 May 2012 13:09:30 -0400 Received: from mail-pb0-f45.google.com ([209.85.160.45]:44998) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1SSWrk-0003q7-MX for qemu-devel@nongnu.org; Thu, 10 May 2012 13:09:24 -0400 Received: by pbbro12 with SMTP id ro12so2900852pbb.4 for ; Thu, 10 May 2012 10:09:22 -0700 (PDT) Message-ID: <4FABF639.4070205@gmail.com> Date: Fri, 11 May 2012 01:09:13 +0800 From: Jiang Liu MIME-Version: 1.0 References: <1315976141-6684-1-git-send-email-akong@redhat.com> <20120510154423.11306.85353.stgit@t> In-Reply-To: <20120510154423.11306.85353.stgit@t> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] [PATCH v3] pci: clean all funcs when hot-removing multifunc device List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Amos Kong Cc: mst@redhat.com, linux-pci@vger.kernel.org, seabios@seabios.org, qemu-devel@nongnu.org, jbarnes@virtuousgeek.org, alex.williamson@redhat.com, kevin@koconnor.net On 05/10/2012 11:44 PM, Amos Kong wrote: > diff --git a/drivers/pci/hotplug/acpiphp_glue.c b/drivers/pci/hotplug/acpiphp_glue.c > index 806c44f..a7442d9 100644 > --- a/drivers/pci/hotplug/acpiphp_glue.c > +++ b/drivers/pci/hotplug/acpiphp_glue.c > @@ -885,7 +885,7 @@ static void disable_bridges(struct pci_bus *bus) > static int disable_device(struct acpiphp_slot *slot) > { > struct acpiphp_func *func; > - struct pci_dev *pdev; > + struct pci_dev *pdev, *tmp; > struct pci_bus *bus = slot->bridge->pci_bus; > > /* The slot will be enabled when func 0 is added, so check > @@ -902,9 +902,10 @@ static int disable_device(struct acpiphp_slot *slot) > func->bridge = NULL; > } > > - pdev = pci_get_slot(slot->bridge->pci_bus, > - PCI_DEVFN(slot->device, func->function)); > - if (pdev) { > + list_for_each_entry_safe(pdev, tmp, &bus->devices, bus_list) { > + if (PCI_SLOT(pdev->devfn) != slot->device) > + continue; > + The pci_bus_sem lock should be acquired when walking the bus->devices list. Otherwise it may cause invalid memory access if another thread is modifying the bus->devices list concurrently. BTW, what's the relationship with "[PATCH v3] hotplug: add device per func in ACPI DSDT tables"? Seems they are both solving the same issue. > pci_stop_bus_device(pdev); > if (pdev->subordinate) { > disable_bridges(pdev->subordinate); > > -- > 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