[PATCH v2 2/2] vfio/pci: Remove console drivers

From: Alex Williamson
Date: Thu Jun 16 2022 - 16:39:12 EST


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. Use the aperture helpers to remove these conflicts.

Reported-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 | 5 +++++
1 file changed, 5 insertions(+)

diff --git a/drivers/vfio/pci/vfio_pci_core.c b/drivers/vfio/pci/vfio_pci_core.c
index a0d69ddaf90d..5b2a6e9f7cf7 100644
--- a/drivers/vfio/pci/vfio_pci_core.c
+++ b/drivers/vfio/pci/vfio_pci_core.c
@@ -10,6 +10,7 @@

#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

+#include <linux/aperture.h>
#include <linux/device.h>
#include <linux/eventfd.h>
#include <linux/file.h>
@@ -1793,6 +1794,10 @@ static int vfio_pci_vga_init(struct vfio_pci_core_device *vdev)
if (!vfio_pci_is_vga(pdev))
return 0;

+ ret = remove_conflicting_pci_devices(pdev, vdev->vdev.ops->name);
+ if (ret)
+ return ret;
+
ret = vga_client_register(pdev, vfio_pci_set_decode);
if (ret)
return ret;