Commit 7d1647dc authored Sep 07, 2015 by Andrew Donnellan Committed by Michael Ellerman Sep 07, 2015

cxl: abort cxl_pci_enable_device_hook() if PCI channel is offline



cxl_pci_enable_device_hook() is called when attempting to enable an AFU
sitting on a vPHB. At present, the state of the underlying CXL card's PCI
channel is only checked when it calls cxl_afu_check_and_enable() at the
very end, after it has already set DMA options and initialised a default
context.

Check the CXL card's link status before setting DMA options or initialising
a default context. If the link is down, print a warning and return
immediately.

Signed-off-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
Acked-by: Ian Munsie <imunsie@au1.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

parent fa144869

drivers/misc/cxl/vphb.c

+6 −0

Original line number	Diff line number	Diff line
		@@ -48,6 +48,12 @@ static bool cxl_pci_enable_device_hook(struct pci_dev *dev)

		phb = pci_bus_to_host(dev->bus);
		afu = (struct cxl_afu *)phb->private_data;

		if (!cxl_adapter_link_ok(afu->adapter)) {
		dev_warn(&dev->dev, "%s: Device link is down, refusing to enable AFU\n", __func__);
		return false;
		}

		set_dma_ops(&dev->dev, &dma_direct_ops);
		set_dma_offset(&dev->dev, PAGE_OFFSET);