An ATA controller in native mode may have one or more channels disabled
and not assigned resources. In that case the existing code crashes trying
to access I/O ports 0-7.

Add the neccessary check.

Signed-off-by: Alan Cox <[EMAIL PROTECTED]>

diff -u --new-file --recursive --exclude-from /usr/src/exclude 
linux.vanilla-2.6.20-rc3-mm1/drivers/ata/libata-sff.c 
linux-2.6.20-rc3-mm1/drivers/ata/libata-sff.c
--- linux.vanilla-2.6.20-rc3-mm1/drivers/ata/libata-sff.c       2007-01-05 
13:09:36.000000000 +0000
+++ linux-2.6.20-rc3-mm1/drivers/ata/libata-sff.c       2007-01-05 
14:08:32.000000000 +0000
@@ -831,6 +831,21 @@
 }
 
 #ifdef CONFIG_PCI
+
+static int ata_resources_present(struct pci_dev *pdev, int port)
+{
+       int i;
+       
+       /* Check the PCI resources for this channel are enabled */
+       port = port * 2;
+       for (i = 0; i < 2; i ++) {
+               if (pci_resource_start(pdev, port + i) == 0 ||
+                       pci_resource_len(pdev, port + i) == 0)
+               return 0;
+       }
+       return 1;
+}
+               
 /**
  *     ata_pci_init_native_mode - Initialize native-mode driver
  *     @pdev:  pci device to be initialized
@@ -862,6 +877,13 @@
 
        probe_ent->irq = pdev->irq;
        probe_ent->irq_flags = IRQF_SHARED;
+       
+       /* Discard disabled ports. Some controllers show their
+          unused channels this way */
+       if (ata_resources_present(pdev, 0) == 0)
+               ports &= ~ATA_PORT_PRIMARY;
+       if (ata_resources_present(pdev, 1) == 0)
+               ports &= ~ATA_PORT_SECONDARY;
 
        if (ports & ATA_PORT_PRIMARY) {
                probe_ent->port[p].cmd_addr = pci_resource_start(pdev, 0);
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to [EMAIL PROTECTED]
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

Reply via email to