Console drivers can create conflicts with PCI resources resulting in userspace getting mmap failures to memory BARs. This is especially evident when trying to re-use the system primary console for userspace drivers. Attempt to remove all nature of conflicting drivers as part of our VGA initialization. Reported-by: Laszlo Ersek <lersek@xxxxxxxxxx> Tested-by: Laszlo Ersek <lersek@xxxxxxxxxx> Suggested-by: Gerd Hoffmann <kraxel@xxxxxxxxxx> Signed-off-by: Alex Williamson <alex.williamson@xxxxxxxxxx> --- drivers/vfio/pci/vfio_pci_core.c | 17 +++++++++++++++++ 1 file changed, 17 insertions(+) diff --git a/drivers/vfio/pci/vfio_pci_core.c b/drivers/vfio/pci/vfio_pci_core.c index a0d69ddaf90d..e0cbcbc2aee1 100644 --- a/drivers/vfio/pci/vfio_pci_core.c +++ b/drivers/vfio/pci/vfio_pci_core.c @@ -13,6 +13,7 @@ #include <linux/device.h> #include <linux/eventfd.h> #include <linux/file.h> +#include <linux/fb.h> #include <linux/interrupt.h> #include <linux/iommu.h> #include <linux/module.h> @@ -29,6 +30,8 @@ #include <linux/vfio_pci_core.h> +#include <drm/drm_aperture.h> + #define DRIVER_AUTHOR "Alex Williamson <alex.williamson@xxxxxxxxxx>" #define DRIVER_DESC "core driver for VFIO based PCI devices" @@ -1793,6 +1796,20 @@ static int vfio_pci_vga_init(struct vfio_pci_core_device *vdev) if (!vfio_pci_is_vga(pdev)) return 0; +#if IS_REACHABLE(CONFIG_DRM) + drm_aperture_detach_platform_drivers(pdev); +#endif + +#if IS_REACHABLE(CONFIG_FB) + ret = remove_conflicting_pci_framebuffers(pdev, vdev->vdev.ops->name); + if (ret) + return ret; +#endif + + ret = vga_remove_vgacon(pdev); + if (ret) + return ret; + ret = vga_client_register(pdev, vfio_pci_set_decode); if (ret) return ret;
