6 files changed, 63 insertions, 10 deletions

diff --git a/arch/x86_64/kernel/e820.c b/arch/x86_64/kernel/e820.c
index 62776c07cff1..222b5b46d2b2 100644
--- a/arch/x86_64/kernel/e820.c
+++ b/arch/x86_64/kernel/e820.c
@@ -76,6 +76,12 @@ static inline int bad_addr(unsigned long *addrp, unsigned long size)
                 *addrp = __pa_symbol(&_end);
                 return 1;
         }
+
+        if (last >= ebda_addr && addr < ebda_addr + ebda_size) {
+                *addrp = ebda_addr + ebda_size;
+                return 1;
+        }
+
         /* XXX ramdisk image here? */ 
         return 0;
 } 
diff --git a/arch/x86_64/kernel/io_apic.c b/arch/x86_64/kernel/io_apic.c
index 77b4c608cca0..0de3ea938830 100644
--- a/arch/x86_64/kernel/io_apic.c
+++ b/arch/x86_64/kernel/io_apic.c
@@ -1777,6 +1777,8 @@ static inline void unlock_ExtINT_logic(void)
         spin_unlock_irqrestore(&ioapic_lock, flags);
 }
 
+int timer_uses_ioapic_pin_0;
+
 /*
  * This code may look a bit paranoid, but it's supposed to cooperate with
  * a wide range of boards and BIOS bugs.  Fortunately only the timer IRQ
@@ -1814,6 +1816,9 @@ static inline void check_timer(void)
         pin2  = ioapic_i8259.pin;
         apic2 = ioapic_i8259.apic;
 
+        if (pin1 == 0)
+                timer_uses_ioapic_pin_0 = 1;
+
         apic_printk(APIC_VERBOSE,KERN_INFO "..TIMER: vector=0x%02X apic1=%d pin1=%d apic2=%d pin2=%d\n",
                 vector, apic1, pin1, apic2, pin2);
 
diff --git a/arch/x86_64/kernel/mpparse.c b/arch/x86_64/kernel/mpparse.c
index b17cf3eba359..083da7e606b1 100644
--- a/arch/x86_64/kernel/mpparse.c
+++ b/arch/x86_64/kernel/mpparse.c
@@ -968,7 +968,17 @@ int mp_register_gsi(u32 gsi, int triggering, int polarity)
                  */
                 int irq = gsi;
                 if (gsi < MAX_GSI_NUM) {
-                        if (gsi > 15)
+                        /*
+                         * Retain the VIA chipset work-around (gsi > 15), but
+                         * avoid a problem where the 8254 timer (IRQ0) is setup
+                         * via an override (so it's not on pin 0 of the ioapic),
+                         * and at the same time, the pin 0 interrupt is a PCI
+                         * type.  The gsi > 15 test could cause these two pins
+                         * to be shared as IRQ0, and they are not shareable.
+                         * So test for this condition, and if necessary, avoid
+                         * the pin collision.
+                         */
+                        if (gsi > 15 || (gsi == 0 && !timer_uses_ioapic_pin_0))
                                 gsi = pci_irq++;
                         /*
                          * Don't assign IRQ used by ACPI SCI
diff --git a/arch/x86_64/kernel/pci-gart.c b/arch/x86_64/kernel/pci-gart.c
index 9d3d76c85ae7..2480d3f08a47 100644
--- a/arch/x86_64/kernel/pci-gart.c
+++ b/arch/x86_64/kernel/pci-gart.c
@@ -639,6 +639,14 @@ static int __init pci_iommu_init(void)
                 return -1;
         }
 
+        i = 0;
+        for_all_nb(dev)
+                i++;
+        if (i > MAX_NB) {
+                printk(KERN_ERR "PCI-GART: Too many northbridges (%ld). Disabled\n", i);
+                return -1;
+        }
+
         printk(KERN_INFO "PCI-DMA: using GART IOMMU.\n");
         aper_size = info.aper_size * 1024 * 1024;       
         iommu_size = check_iommu_size(info.aper_base, aper_size); 
diff --git a/arch/x86_64/kernel/setup.c b/arch/x86_64/kernel/setup.c
index ebc3c33b1c6c..f0870bef24d1 100644
--- a/arch/x86_64/kernel/setup.c
+++ b/arch/x86_64/kernel/setup.c
@@ -571,17 +571,28 @@ static inline void copy_edd(void)
 #endif
 
 #define EBDA_ADDR_POINTER 0x40E
-static void __init reserve_ebda_region(void)
+
+unsigned __initdata ebda_addr;
+unsigned __initdata ebda_size;
+
+static void discover_ebda(void)
 {
-        unsigned int addr;
-        /** 
+        /*
          * there is a real-mode segmented pointer pointing to the 
          * 4K EBDA area at 0x40E
          */
-        addr = *(unsigned short *)phys_to_virt(EBDA_ADDR_POINTER);
-        addr <<= 4;
-        if (addr)
-                reserve_bootmem_generic(addr, PAGE_SIZE);
+        ebda_addr = *(unsigned short *)EBDA_ADDR_POINTER;
+        ebda_addr <<= 4;
+
+        ebda_size = *(unsigned short *)(unsigned long)ebda_addr;
+
+        /* Round EBDA up to pages */
+        if (ebda_size == 0)
+                ebda_size = 1;
+        ebda_size <<= 10;
+        ebda_size = round_up(ebda_size + (ebda_addr & ~PAGE_MASK), PAGE_SIZE);
+        if (ebda_size > 64*1024)
+                ebda_size = 64*1024;
 }
 
 void __init setup_arch(char **cmdline_p)
@@ -627,6 +638,8 @@ void __init setup_arch(char **cmdline_p)
 
         check_efer();
 
+        discover_ebda();
+
         init_memory_mapping(0, (end_pfn_map << PAGE_SHIFT));
 
         dmi_scan_machine();
@@ -669,7 +682,8 @@ void __init setup_arch(char **cmdline_p)
         reserve_bootmem_generic(0, PAGE_SIZE);
 
         /* reserve ebda region */
-        reserve_ebda_region();
+        if (ebda_addr)
+                reserve_bootmem_generic(ebda_addr, ebda_size);
 
 #ifdef CONFIG_SMP
         /*
diff --git a/arch/x86_64/kernel/traps.c b/arch/x86_64/kernel/traps.c
index 2700b1375c1f..6b87268c5c2e 100644
--- a/arch/x86_64/kernel/traps.c
+++ b/arch/x86_64/kernel/traps.c
@@ -385,6 +385,7 @@ void out_of_line_bug(void)
 
 static DEFINE_SPINLOCK(die_lock);
 static int die_owner = -1;
+static unsigned int die_nest_count;
 
 unsigned __kprobes long oops_begin(void)
 {
@@ -399,6 +400,7 @@ unsigned __kprobes long oops_begin(void)
                 else
                         spin_lock(&die_lock);
         }
+        die_nest_count++;
         die_owner = cpu;
         console_verbose();
         bust_spinlocks(1);
@@ -409,7 +411,13 @@ void __kprobes oops_end(unsigned long flags)
 { 
         die_owner = -1;
         bust_spinlocks(0);
-        spin_unlock_irqrestore(&die_lock, flags);
+        die_nest_count--;
+        if (die_nest_count)
+                /* We still own the lock */
+                local_irq_restore(flags);
+        else
+                /* Nest count reaches zero, release the lock. */
+                spin_unlock_irqrestore(&die_lock, flags);
         if (panic_on_oops)
                 panic("Oops");
 }
@@ -464,6 +472,8 @@ void __kprobes die_nmi(char *str, struct pt_regs *regs)
                 panic("nmi watchdog");
         printk("console shuts up ...\n");
         oops_end(flags);
+        nmi_exit();
+        local_irq_enable();
         do_exit(SIGSEGV);
 }