1 files changed, 23 insertions, 7 deletions

diff --git a/drivers/gpu/vga/vgaarb.c b/drivers/gpu/vga/vgaarb.c
index 1ac0c93603c9..441e38c95a85 100644
--- a/drivers/gpu/vga/vgaarb.c
+++ b/drivers/gpu/vga/vgaarb.c
@@ -20,6 +20,7 @@
 #include <linux/spinlock.h>
 #include <linux/poll.h>
 #include <linux/miscdevice.h>
+#include <linux/slab.h>
 
 #include <linux/uaccess.h>
 
@@ -688,7 +689,7 @@ EXPORT_SYMBOL(vga_client_register);
  * the arbiter.
  */
 
-#define MAX_USER_CARDS         16
+#define MAX_USER_CARDS         CONFIG_VGA_ARB_MAX_GPUS
 #define PCI_INVALID_CARD       ((struct pci_dev *)-1UL)
 
 /*
@@ -954,6 +955,7 @@ static ssize_t vga_arb_write(struct file *file, const char __user * buf,
                 }
 
         } else if (strncmp(curr_pos, "target ", 7) == 0) {
+                struct pci_bus *pbus;
                 unsigned int domain, bus, devfn;
                 struct vga_device *vgadev;
 
@@ -961,7 +963,7 @@ static ssize_t vga_arb_write(struct file *file, const char __user * buf,
                 remaining -= 7;
                 pr_devel("client 0x%p called 'target'\n", priv);
                 /* if target is default */
-                if (!strncmp(buf, "default", 7))
+                if (!strncmp(curr_pos, "default", 7))
                         pdev = pci_dev_get(vga_default_device());
                 else {
                         if (!vga_pci_str_to_vars(curr_pos, remaining,
@@ -969,18 +971,31 @@ static ssize_t vga_arb_write(struct file *file, const char __user * buf,
                                 ret_val = -EPROTO;
                                 goto done;
                         }
-
-                        pdev = pci_get_bus_and_slot(bus, devfn);
+                        pr_devel("vgaarb: %s ==> %x:%x:%x.%x\n", curr_pos,
+                                domain, bus, PCI_SLOT(devfn), PCI_FUNC(devfn));
+
+                        pbus = pci_find_bus(domain, bus);
+                        pr_devel("vgaarb: pbus %p\n", pbus);
+                        if (pbus == NULL) {
+                                pr_err("vgaarb: invalid PCI domain and/or bus address %x:%x\n",
+                                        domain, bus);
+                                ret_val = -ENODEV;
+                                goto done;
+                        }
+                        pdev = pci_get_slot(pbus, devfn);
+                        pr_devel("vgaarb: pdev %p\n", pdev);
                         if (!pdev) {
-                                pr_info("vgaarb: invalid PCI address!\n");
+                                pr_err("vgaarb: invalid PCI address %x:%x\n",
+                                        bus, devfn);
                                 ret_val = -ENODEV;
                                 goto done;
                         }
                 }
 
                 vgadev = vgadev_find(pdev);
+                pr_devel("vgaarb: vgadev %p\n", vgadev);
                 if (vgadev == NULL) {
-                        pr_info("vgaarb: this pci device is not a vga device\n");
+                        pr_err("vgaarb: this pci device is not a vga device\n");
                         pci_dev_put(pdev);
                         ret_val = -ENODEV;
                         goto done;
@@ -998,7 +1013,8 @@ static ssize_t vga_arb_write(struct file *file, const char __user * buf,
                         }
                 }
                 if (i == MAX_USER_CARDS) {
-                        pr_err("vgaarb: maximum user cards number reached!\n");
+                        pr_err("vgaarb: maximum user cards (%d) number reached!\n",
+                                MAX_USER_CARDS);
                         pci_dev_put(pdev);
                         /* XXX: which value to return? */
                         ret_val =  -ENOMEM;