From 45e869714489431625c569d21fc952428d761476 Mon Sep 17 00:00:00 2001 From: Arnd Bergmann Date: Fri, 30 Dec 2016 08:13:47 -0700 Subject: [PATCH] vfio-pci: use 32-bit comparisons for register address for gcc-4.5 Using ancient compilers (gcc-4.5 or older) on ARM, we get a link failure with the vfio-pci driver: ERROR: "__aeabi_lcmp" [drivers/vfio/pci/vfio-pci.ko] undefined! The reason is that the compiler tries to do a comparison of a 64-bit range. This changes it to convert to a 32-bit number explicitly first, as newer compilers do for themselves. Signed-off-by: Arnd Bergmann Signed-off-by: Alex Williamson --- drivers/vfio/pci/vfio_pci_rdwr.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/drivers/vfio/pci/vfio_pci_rdwr.c b/drivers/vfio/pci/vfio_pci_rdwr.c index 5ffd1d9ad4bd..357243d76f10 100644 --- a/drivers/vfio/pci/vfio_pci_rdwr.c +++ b/drivers/vfio/pci/vfio_pci_rdwr.c @@ -193,7 +193,10 @@ ssize_t vfio_pci_vga_rw(struct vfio_pci_device *vdev, char __user *buf, if (!vdev->has_vga) return -EINVAL; - switch (pos) { + if (pos > 0xbfffful) + return -EINVAL; + + switch ((u32)pos) { case 0xa0000 ... 0xbffff: count = min(count, (size_t)(0xc0000 - pos)); iomem = ioremap_nocache(0xa0000, 0xbffff - 0xa0000 + 1);