> -----Original Message----- > From: Long Li [mailto:longli@xxxxxxxxxxxxxxxxxxxxxx] > Sent: Monday, January 23, 2017 9:46 PM > To: KY Srinivasan <kys@xxxxxxxxxxxxx>; Haiyang Zhang > <haiyangz@xxxxxxxxxxxxx>; Bjorn Helgaas <bhelgaas@xxxxxxxxxx> > Cc: devel@xxxxxxxxxxxxxxxxxxxxxx; linux-pci@xxxxxxxxxxxxxxx; linux- > kernel@xxxxxxxxxxxxxxx; Long Li <longli@xxxxxxxxxxxxx> > Subject: [Resend PATCH 2/2 v3] pci-hyperv: lock pci bus on device eject > > [This sender failed our fraud detection checks and may not be who they > appear to be. Learn about spoofing at http://aka.ms/LearnAboutSpoofing] > > From: Long Li <longli@xxxxxxxxxxxxx> > > A PCI_EJECT message can arrive at the same time we are calling > pci_scan_child_bus in the workqueue for the previous PCI_BUS_RELATIONS > message or in create_root_hv_pci_bus(), in this case we could potentailly > modify the bus from multiple places. Properly lock the bus access. > > Thanks Dexuan Cui <decui@xxxxxxxxxxxxx> for pointing out the race > condition in create_root_hv_pci_bus(). > > Signed-off-by: Long Li <longli@xxxxxxxxxxxxx> > Reported-by: Xiaofeng Wang <xiaofwan@xxxxxxxxxx> Acked-by: K. Y. Srinivasan <kys@xxxxxxxxxxxxx> > --- > drivers/pci/host/pci-hyperv.c | 4 ++++ > 1 file changed, 4 insertions(+) > > diff --git a/drivers/pci/host/pci-hyperv.c b/drivers/pci/host/pci-hyperv.c > index 4a37598..33c75c9 100644 > --- a/drivers/pci/host/pci-hyperv.c > +++ b/drivers/pci/host/pci-hyperv.c > @@ -1198,9 +1198,11 @@ static int create_root_hv_pci_bus(struct > hv_pcibus_device *hbus) > hbus->pci_bus->msi = &hbus->msi_chip; > hbus->pci_bus->msi->dev = &hbus->hdev->device; > > + pci_lock_rescan_remove(); > pci_scan_child_bus(hbus->pci_bus); > pci_bus_assign_resources(hbus->pci_bus); > pci_bus_add_devices(hbus->pci_bus); > + pci_unlock_rescan_remove(); > hbus->state = hv_pcibus_installed; > return 0; > } > @@ -1590,8 +1592,10 @@ static void hv_eject_device_work(struct > work_struct *work) > pdev = pci_get_domain_bus_and_slot(hpdev->hbus->sysdata.domain, > 0, > wslot); > if (pdev) { > + pci_lock_rescan_remove(); > pci_stop_and_remove_bus_device(pdev); > pci_dev_put(pdev); > + pci_unlock_rescan_remove(); > } > > memset(&ctxt, 0, sizeof(ctxt)); > -- > 1.8.5.6 _______________________________________________ devel mailing list devel@xxxxxxxxxxxxxxxxxxxxxx http://driverdev.linuxdriverproject.org/mailman/listinfo/driverdev-devel
