From patchwork Thu Oct 18 10:03:36 2012 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Subject: [3/5] xen-pcifront: handle backend CLOSED without CLOSING Date: Thu, 18 Oct 2012 00:03:36 -0000 From: David Vrabel X-Patchwork-Id: 192257 Message-Id: <1350554618-14582-3-git-send-email-david.vrabel@citrix.com> To: xen-devel@lists.xen.org Cc: "David Vrabel" , Konrad Rzeszutek Wilk , linux-kernel@vger.kernel.org, linux-pci@vger.kernel.org, Bjorn Helgaas From: David Vrabel Backend drivers shouldn't transistion to CLOSED unless the frontend is CLOSED. If a backend does transition to CLOSED too soon then the frontend may not see the CLOSING state and will not properly shutdown. So, treat an unexpected backend CLOSED state the same as CLOSING. Signed-off-by: David Vrabel Acked-by: Konrad Rzeszutek Wilk --- Cc: linux-pci@vger.kernel.org Cc: Bjorn Helgaas --- drivers/pci/xen-pcifront.c | 5 ++++- 1 files changed, 4 insertions(+), 1 deletions(-) diff --git a/drivers/pci/xen-pcifront.c b/drivers/pci/xen-pcifront.c index 0aab85a..a0c7312 100644 --- a/drivers/pci/xen-pcifront.c +++ b/drivers/pci/xen-pcifront.c @@ -1068,13 +1068,16 @@ static void __init_refok pcifront_backend_changed(struct xenbus_device *xdev, case XenbusStateInitialising: case XenbusStateInitWait: case XenbusStateInitialised: - case XenbusStateClosed: break; case XenbusStateConnected: pcifront_try_connect(pdev); break; + case XenbusStateClosed: + if (xdev->state == XenbusStateClosed) + break; + /* Missed the backend's CLOSING state -- fallthrough */ case XenbusStateClosing: dev_warn(&xdev->dev, "backend going away!\n"); pcifront_try_disconnect(pdev);