Merge branch 'core-locking-for-linus' of git://git.kernel.org/pub/scm/linux/kernel...

[pandora-kernel.git] / drivers / iommu / intr_remapping.c

diff --git a/drivers/iommu/intr_remapping.c b/drivers/iommu/intr_remapping.c
index 73a9034..07c9f18 100644 (file)
--- a/drivers/iommu/intr_remapping.c
+++ b/drivers/iommu/intr_remapping.c
@@ -21,6 +21,7 @@ int intr_remapping_enabled;
 
 static int disable_intremap;
 static int disable_sourceid_checking;
+static int no_x2apic_optout;
 
 static __init int setup_nointremap(char *str)
 {
@@ -34,12 +35,20 @@ static __init int setup_intremap(char *str)
        if (!str)
                return -EINVAL;
 
-       if (!strncmp(str, "on", 2))
-               disable_intremap = 0;
-       else if (!strncmp(str, "off", 3))
-               disable_intremap = 1;
-       else if (!strncmp(str, "nosid", 5))
-               disable_sourceid_checking = 1;
+       while (*str) {
+               if (!strncmp(str, "on", 2))
+                       disable_intremap = 0;
+               else if (!strncmp(str, "off", 3))
+                       disable_intremap = 1;
+               else if (!strncmp(str, "nosid", 5))
+                       disable_sourceid_checking = 1;
+               else if (!strncmp(str, "no_x2apic_optout", 16))
+                       no_x2apic_optout = 1;
+
+               str += strcspn(str, ",");
+               while (*str == ',')
+                       str++;
+       }
 
        return 0;
 }
@@ -501,6 +510,15 @@ end:
        raw_spin_unlock_irqrestore(&iommu->register_lock, flags);
 }
 
+static int __init dmar_x2apic_optout(void)
+{
+       struct acpi_table_dmar *dmar;
+       dmar = (struct acpi_table_dmar *)dmar_tbl;
+       if (!dmar || no_x2apic_optout)
+               return 0;
+       return dmar->flags & DMAR_X2APIC_OPT_OUT;
+}
+
 int __init intr_remapping_supported(void)
 {
        struct dmar_drhd_unit *drhd;
@@ -521,16 +539,25 @@ int __init intr_remapping_supported(void)
        return 1;
 }
 
-int __init enable_intr_remapping(int eim)
+int __init enable_intr_remapping(void)
 {
        struct dmar_drhd_unit *drhd;
        int setup = 0;
+       int eim = 0;
 
        if (parse_ioapics_under_ir() != 1) {
                printk(KERN_INFO "Not enable interrupt remapping\n");
                return -1;
        }
 
+       if (x2apic_supported()) {
+               eim = !dmar_x2apic_optout();
+               WARN(!eim, KERN_WARNING
+                          "Your BIOS is broken and requested that x2apic be disabled\n"
+                          "This will leave your machine vulnerable to irq-injection attacks\n"
+                          "Use 'intremap=no_x2apic_optout' to override BIOS request\n");
+       }
+
        for_each_drhd_unit(drhd) {
                struct intel_iommu *iommu = drhd->iommu;
 
@@ -606,8 +633,9 @@ int __init enable_intr_remapping(int eim)
                goto error;
 
        intr_remapping_enabled = 1;
+       pr_info("Enabled IRQ remapping in %s mode\n", eim ? "x2apic" : "xapic");
 
-       return 0;
+       return eim ? IRQ_REMAP_X2APIC_MODE : IRQ_REMAP_XAPIC_MODE;
 
 error:
        /*
@@ -745,6 +773,15 @@ int __init parse_ioapics_under_ir(void)
        return ir_supported;
 }
 
+int ir_dev_scope_init(void)
+{
+       if (!intr_remapping_enabled)
+               return 0;
+
+       return dmar_dev_scope_init();
+}
+rootfs_initcall(ir_dev_scope_init);
+
 void disable_intr_remapping(void)
 {
        struct dmar_drhd_unit *drhd;