From: Manish Honap <[email protected]> devm_cxl_probe_mem() maps the component registers through the CXL core, which by default claims each HDM and RAS sub-block. That collides with the full-BAR request vfio-pci-core makes when the guest opens the device.
After the component registers are discovered, declare the containing BAR owned with cxl_reg_map_add_owned_resource(). The core then ioremaps the sub-blocks without requesting them, so vfio-pci-core owns the whole BAR and the requests do not collide. Assisted-by: LLM Signed-off-by: Manish Honap <[email protected]> --- drivers/vfio/pci/cxl/vfio_cxl_core.c | 9 +++++++++ 1 file changed, 9 insertions(+) diff --git a/drivers/vfio/pci/cxl/vfio_cxl_core.c b/drivers/vfio/pci/cxl/vfio_cxl_core.c index 0d92e6a409c1..5c8a63833a43 100644 --- a/drivers/vfio/pci/cxl/vfio_cxl_core.c +++ b/drivers/vfio/pci/cxl/vfio_cxl_core.c @@ -89,6 +89,15 @@ static int vfio_cxl_init_device(struct vfio_pci_core_device *vdev) goto err; } + /* + * vfio-pci-core requests the whole component-register BAR when the + * guest opens the device. Declare that BAR owned so the CXL core + * ioremaps the HDM and RAS sub-blocks without claiming them, and the + * full-BAR request does not collide. + */ + cxl_reg_map_add_owned_resource(&cxl->cxlds.reg_map, + pci_resource_n(pdev, pdev->hdm->hdm_bar)); + if (!cxl->cxlds.reg_map.component_map.hdm_decoder.valid) { pci_err(pdev, "vfio-cxl: HDM decoder registers not found\n"); ret = -ENODEV; -- 2.25.1
