diff options
| author | Long Li <longli@microsoft.com> | 2017-03-23 14:58:32 -0700 |
|---|---|---|
| committer | Bjorn Helgaas <bhelgaas@google.com> | 2017-03-24 09:54:56 -0500 |
| commit | 414428c5da1c71986727c2fa5cdf1ed071e398d7 (patch) | |
| tree | 9d08139b53727f300a80b592bfae5e931634b6f8 /drivers/pci/host | |
| parent | d3a78d8bf759d8848339dcc367c4c1678b57a08b (diff) | |
| download | linux-414428c5da1c71986727c2fa5cdf1ed071e398d7.tar.gz linux-414428c5da1c71986727c2fa5cdf1ed071e398d7.tar.bz2 linux-414428c5da1c71986727c2fa5cdf1ed071e398d7.zip | |
PCI: hv: Lock PCI bus on device eject
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 potentially
modify the bus from multiple places.
Properly lock the bus access.
Thanks Dexuan Cui <decui@microsoft.com> for pointing out the race condition
in create_root_hv_pci_bus().
Reported-by: Xiaofeng Wang <xiaofwan@redhat.com>
Signed-off-by: Long Li <longli@microsoft.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: K. Y. Srinivasan <kys@microsoft.com>
Diffstat (limited to 'drivers/pci/host')
| -rw-r--r-- | drivers/pci/host/pci-hyperv.c | 4 |
1 files changed, 4 insertions, 0 deletions
diff --git a/drivers/pci/host/pci-hyperv.c b/drivers/pci/host/pci-hyperv.c index 39fafda4deff..a1b3c1957d43 100644 --- a/drivers/pci/host/pci-hyperv.c +++ b/drivers/pci/host/pci-hyperv.c @@ -1209,9 +1209,11 @@ 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; } @@ -1612,8 +1614,10 @@ 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(); } spin_lock_irqsave(&hpdev->hbus->device_list_lock, flags); |