From 80ba77dfbce85f2d1be54847de3c866de1b18a9a Mon Sep 17 00:00:00 2001 From: Konrad Rzeszutek Wilk Date: Wed, 5 Sep 2012 16:35:20 -0400 Subject: [PATCH] xen/pciback: Fix proper FLR steps. When we do FLR and save PCI config we did it in the wrong order. The end result was that if a PCI device was unbind from its driver, then binded to xen-pciback, and then back to its driver we would get: > lspci -s 04:00.0 04:00.0 Ethernet controller: Intel Corporation 82574L Gigabit Network Connection 13:42:12 # 4 :~/ > echo "0000:04:00.0" > /sys/bus/pci/drivers/pciback/unbind > modprobe e1000e e1000e: Intel(R) PRO/1000 Network Driver - 2.0.0-k e1000e: Copyright(c) 1999 - 2012 Intel Corporation. e1000e 0000:04:00.0: Disabling ASPM L0s L1 e1000e 0000:04:00.0: enabling device (0000 -> 0002) xen: registering gsi 48 triggering 0 polarity 1 Already setup the GSI :48 e1000e 0000:04:00.0: Interrupt Throttling Rate (ints/sec) set to dynamic conservative mode e1000e: probe of 0000:04:00.0 failed with error -2 This fixes it by first saving the PCI configuration space, then doing the FLR. Reported-by: Ren, Yongjie Reported-and-Tested-by: Tobias Geiger Signed-off-by: Konrad Rzeszutek Wilk CC: stable@vger.kernel.org --- drivers/xen/xen-pciback/pci_stub.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/drivers/xen/xen-pciback/pci_stub.c b/drivers/xen/xen-pciback/pci_stub.c index 097e536e8672..03342728bf23 100644 --- a/drivers/xen/xen-pciback/pci_stub.c +++ b/drivers/xen/xen-pciback/pci_stub.c @@ -353,16 +353,16 @@ static int __devinit pcistub_init_device(struct pci_dev *dev) if (err) goto config_release; - dev_dbg(&dev->dev, "reseting (FLR, D3, etc) the device\n"); - __pci_reset_function_locked(dev); - /* We need the device active to save the state. */ dev_dbg(&dev->dev, "save state of device\n"); pci_save_state(dev); dev_data->pci_saved_state = pci_store_saved_state(dev); if (!dev_data->pci_saved_state) dev_err(&dev->dev, "Could not store PCI conf saved state!\n"); - + else { + dev_dbg(&dev->dev, "reseting (FLR, D3, etc) the device\n"); + __pci_reset_function_locked(dev); + } /* Now disable the device (this also ensures some private device * data is setup before we export) */