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);
 }