diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c index 09807a65ef87..e601564709c6 100644 --- a/drivers/pci/pci.c +++ b/drivers/pci/pci.c @@ -6202,6 +6202,18 @@ int pci_set_vga_state(struct pci_dev *dev, bool decode, cmd &= ~PCI_BRIDGE_CTL_VGA; pci_write_config_word(bridge, PCI_BRIDGE_CONTROL, cmd); + + + /* + * VGA Enable may not be writable if bridge doesn't + * support it. + */ + if (decode) { + pci_read_config_word(bridge, PCI_BRIDGE_CONTROL, + &cmd); + if (!(cmd & PCI_BRIDGE_CTL_VGA)) + return -EIO; + } } bus = bus->parent; } diff --git a/drivers/pci/vgaarb.c b/drivers/pci/vgaarb.c index d9383bf541e7..c360eee11dd9 100644 --- a/drivers/pci/vgaarb.c +++ b/drivers/pci/vgaarb.c @@ -215,6 +215,7 @@ static struct vga_device *__vga_tryget(struct vga_device *vgadev, struct vga_device *conflict; unsigned int pci_bits; u32 flags = 0; + int err; /* * Account for "normal" resources to lock. If we decode the legacy, @@ -307,7 +308,9 @@ static struct vga_device *__vga_tryget(struct vga_device *vgadev, if (change_bridge) flags |= PCI_VGA_STATE_CHANGE_BRIDGE; - pci_set_vga_state(conflict->pdev, false, pci_bits, flags); + err = pci_set_vga_state(conflict->pdev, false, pci_bits, flags); + if (err) + return ERR_PTR(err); conflict->owns &= ~match; /* If we disabled normal decoding, reflect it in owns */ @@ -337,7 +340,9 @@ static struct vga_device *__vga_tryget(struct vga_device *vgadev, if (wants & VGA_RSRC_LEGACY_MASK) flags |= PCI_VGA_STATE_CHANGE_BRIDGE; - pci_set_vga_state(vgadev->pdev, true, pci_bits, flags); + err = pci_set_vga_state(vgadev->pdev, true, pci_bits, flags); + if (err) + return ERR_PTR(err); vgadev->owns |= wants; lock_them: @@ -455,6 +460,10 @@ int vga_get(struct pci_dev *pdev, unsigned int rsrc, int interruptible) } conflict = __vga_tryget(vgadev, rsrc); spin_unlock_irqrestore(&vga_lock, flags); + if (IS_ERR(conflict)) { + rc = PTR_ERR(conflict); + break; + } if (conflict == NULL) break; @@ -1134,6 +1143,7 @@ static ssize_t vga_arb_write(struct file *file, const char __user *buf, char kbuf[64], *curr_pos; size_t remaining = count; + int err; int ret_val; int i; @@ -1165,7 +1175,11 @@ static ssize_t vga_arb_write(struct file *file, const char __user *buf, goto done; } - vga_get_uninterruptible(pdev, io_state); + err = vga_get_uninterruptible(pdev, io_state); + if (err) { + ret_val = err; + goto done; + } /* Update the client's locks lists */ for (i = 0; i < MAX_USER_CARDS; i++) {