11 files changed, 305 insertions, 87 deletions

diff --git a/arch/x86_64/kernel/aperture.c b/arch/x86_64/kernel/aperture.c
index 504e63474993..c9a6b812e926 100644
--- a/arch/x86_64/kernel/aperture.c
+++ b/arch/x86_64/kernel/aperture.c
@@ -40,11 +40,7 @@ int fix_aperture __initdata = 1;
 
 static u32 __init allocate_aperture(void) 
 {
-#ifdef CONFIG_DISCONTIGMEM
         pg_data_t *nd0 = NODE_DATA(0);
-#else
-        pg_data_t *nd0 = &contig_page_data;
-#endif  
         u32 aper_size;
         void *p; 
 
diff --git a/arch/x86_64/kernel/early_printk.c b/arch/x86_64/kernel/early_printk.c
index e3a19e8ebbf8..9631c747c5e3 100644
--- a/arch/x86_64/kernel/early_printk.c
+++ b/arch/x86_64/kernel/early_printk.c
@@ -2,20 +2,24 @@
 #include <linux/kernel.h>
 #include <linux/init.h>
 #include <linux/string.h>
+#include <linux/tty.h>
 #include <asm/io.h>
 #include <asm/processor.h>
 
 /* Simple VGA output */
 
 #ifdef __i386__
+#include <asm/setup.h>
 #define VGABASE         (__ISA_IO_base + 0xb8000)
 #else
+#include <asm/bootsetup.h>
 #define VGABASE         ((void __iomem *)0xffffffff800b8000UL)
 #endif
 
-#define MAX_YPOS        25
-#define MAX_XPOS        80
+#define MAX_YPOS        max_ypos
+#define MAX_XPOS        max_xpos
 
+static int max_ypos = 25, max_xpos = 80;
 static int current_ypos = 1, current_xpos = 0; 
 
 static void early_vga_write(struct console *con, const char *str, unsigned n)
@@ -196,7 +200,10 @@ int __init setup_early_printk(char *opt)
         } else if (!strncmp(buf, "ttyS", 4)) { 
                 early_serial_init(buf);
                 early_console = &early_serial_console;          
-        } else if (!strncmp(buf, "vga", 3)) {
+        } else if (!strncmp(buf, "vga", 3)
+                   && SCREEN_INFO.orig_video_isVGA == 1) {
+                max_xpos = SCREEN_INFO.orig_video_cols;
+                max_ypos = SCREEN_INFO.orig_video_lines;
                 early_console = &early_vga_console; 
         }
         early_console_initialized = 1;
diff --git a/arch/x86_64/kernel/head64.c b/arch/x86_64/kernel/head64.c
index 0f8c78dcd38c..cf6ab147a2a5 100644
--- a/arch/x86_64/kernel/head64.c
+++ b/arch/x86_64/kernel/head64.c
@@ -94,7 +94,7 @@ void __init x86_64_start_kernel(char * real_mode_data)
         s = strstr(saved_command_line, "earlyprintk=");
         if (s != NULL)
                 setup_early_printk(s);
-#ifdef CONFIG_DISCONTIGMEM
+#ifdef CONFIG_NUMA
         s = strstr(saved_command_line, "numa=");
         if (s != NULL)
                 numa_setup(s+5);
diff --git a/arch/x86_64/kernel/i8259.c b/arch/x86_64/kernel/i8259.c
index 7873d9ba8814..19eafa0aa95c 100644
--- a/arch/x86_64/kernel/i8259.c
+++ b/arch/x86_64/kernel/i8259.c
@@ -157,14 +157,13 @@ static unsigned int startup_8259A_irq(unsigned int irq)
 }
 
 static struct hw_interrupt_type i8259A_irq_type = {
-        "XT-PIC",
-        startup_8259A_irq,
-        shutdown_8259A_irq,
-        enable_8259A_irq,
-        disable_8259A_irq,
-        mask_and_ack_8259A,
-        end_8259A_irq,
-        NULL
+        .typename = "XT-PIC",
+        .startup = startup_8259A_irq,
+        .shutdown = shutdown_8259A_irq,
+        .enable = enable_8259A_irq,
+        .disable = disable_8259A_irq,
+        .ack = mask_and_ack_8259A,
+        .end = end_8259A_irq,
 };
 
 /*
diff --git a/arch/x86_64/kernel/kprobes.c b/arch/x86_64/kernel/kprobes.c
index f77f8a0ff187..4e680f87a75f 100644
--- a/arch/x86_64/kernel/kprobes.c
+++ b/arch/x86_64/kernel/kprobes.c
@@ -27,6 +27,8 @@
  *              <prasanna@in.ibm.com> adapted for x86_64
  * 2005-Mar     Roland McGrath <roland@redhat.com>
  *              Fixed to handle %rip-relative addressing mode correctly.
+ * 2005-May     Rusty Lynch <rusty.lynch@intel.com>
+ *              Added function return probes functionality
  */
 
 #include <linux/config.h>
@@ -37,18 +39,16 @@
 #include <linux/slab.h>
 #include <linux/preempt.h>
 #include <linux/moduleloader.h>
-
+#include <asm/cacheflush.h>
 #include <asm/pgtable.h>
 #include <asm/kdebug.h>
 
 static DECLARE_MUTEX(kprobe_mutex);
 
-/* kprobe_status settings */
-#define KPROBE_HIT_ACTIVE       0x00000001
-#define KPROBE_HIT_SS           0x00000002
-
 static struct kprobe *current_kprobe;
 static unsigned long kprobe_status, kprobe_old_rflags, kprobe_saved_rflags;
+static struct kprobe *kprobe_prev;
+static unsigned long kprobe_status_prev, kprobe_old_rflags_prev, kprobe_saved_rflags_prev;
 static struct pt_regs jprobe_saved_regs;
 static long *jprobe_saved_rsp;
 static kprobe_opcode_t *get_insn_slot(void);
@@ -214,6 +214,21 @@ void arch_copy_kprobe(struct kprobe *p)
                 BUG_ON((s64) (s32) disp != disp); /* Sanity check.  */
                 *ripdisp = disp;
         }
+        p->opcode = *p->addr;
+}
+
+void arch_arm_kprobe(struct kprobe *p)
+{
+        *p->addr = BREAKPOINT_INSTRUCTION;
+        flush_icache_range((unsigned long) p->addr,
+                           (unsigned long) p->addr + sizeof(kprobe_opcode_t));
+}
+
+void arch_disarm_kprobe(struct kprobe *p)
+{
+        *p->addr = p->opcode;
+        flush_icache_range((unsigned long) p->addr,
+                           (unsigned long) p->addr + sizeof(kprobe_opcode_t));
 }
 
 void arch_remove_kprobe(struct kprobe *p)
@@ -223,10 +238,29 @@ void arch_remove_kprobe(struct kprobe *p)
         down(&kprobe_mutex);
 }
 
-static inline void disarm_kprobe(struct kprobe *p, struct pt_regs *regs)
+static inline void save_previous_kprobe(void)
 {
-        *p->addr = p->opcode;
-        regs->rip = (unsigned long)p->addr;
+        kprobe_prev = current_kprobe;
+        kprobe_status_prev = kprobe_status;
+        kprobe_old_rflags_prev = kprobe_old_rflags;
+        kprobe_saved_rflags_prev = kprobe_saved_rflags;
+}
+
+static inline void restore_previous_kprobe(void)
+{
+        current_kprobe = kprobe_prev;
+        kprobe_status = kprobe_status_prev;
+        kprobe_old_rflags = kprobe_old_rflags_prev;
+        kprobe_saved_rflags = kprobe_saved_rflags_prev;
+}
+
+static inline void set_current_kprobe(struct kprobe *p, struct pt_regs *regs)
+{
+        current_kprobe = p;
+        kprobe_saved_rflags = kprobe_old_rflags
+                = (regs->eflags & (TF_MASK | IF_MASK));
+        if (is_IF_modifier(p->ainsn.insn))
+                kprobe_saved_rflags &= ~IF_MASK;
 }
 
 static void prepare_singlestep(struct kprobe *p, struct pt_regs *regs)
@@ -240,6 +274,50 @@ static void prepare_singlestep(struct kprobe *p, struct pt_regs *regs)
                 regs->rip = (unsigned long)p->ainsn.insn;
 }
 
+struct task_struct  *arch_get_kprobe_task(void *ptr)
+{
+        return ((struct thread_info *) (((unsigned long) ptr) &
+                                        (~(THREAD_SIZE -1))))->task;
+}
+
+void arch_prepare_kretprobe(struct kretprobe *rp, struct pt_regs *regs)
+{
+        unsigned long *sara = (unsigned long *)regs->rsp;
+        struct kretprobe_instance *ri;
+        static void *orig_ret_addr;
+
+        /*
+         * Save the return address when the return probe hits
+         * the first time, and use it to populate the (krprobe
+         * instance)->ret_addr for subsequent return probes at
+         * the same addrress since stack address would have
+         * the kretprobe_trampoline by then.
+         */
+        if (((void*) *sara) != kretprobe_trampoline)
+                orig_ret_addr = (void*) *sara;
+
+        if ((ri = get_free_rp_inst(rp)) != NULL) {
+                ri->rp = rp;
+                ri->stack_addr = sara;
+                ri->ret_addr = orig_ret_addr;
+                add_rp_inst(ri);
+                /* Replace the return addr with trampoline addr */
+                *sara = (unsigned long) &kretprobe_trampoline;
+        } else {
+                rp->nmissed++;
+        }
+}
+
+void arch_kprobe_flush_task(struct task_struct *tk)
+{
+        struct kretprobe_instance *ri;
+        while ((ri = get_rp_inst_tsk(tk)) != NULL) {
+                *((unsigned long *)(ri->stack_addr)) =
+                                        (unsigned long) ri->ret_addr;
+                recycle_rp_inst(ri);
+        }
+}
+
 /*
  * Interrupts are disabled on entry as trap3 is an interrupt gate and they
  * remain disabled thorough out this function.
@@ -264,9 +342,30 @@ int kprobe_handler(struct pt_regs *regs)
                                 regs->eflags |= kprobe_saved_rflags;
                                 unlock_kprobes();
                                 goto no_kprobe;
+                        } else if (kprobe_status == KPROBE_HIT_SSDONE) {
+                                /* TODO: Provide re-entrancy from
+                                 * post_kprobes_handler() and avoid exception
+                                 * stack corruption while single-stepping on
+                                 * the instruction of the new probe.
+                                 */
+                                arch_disarm_kprobe(p);
+                                regs->rip = (unsigned long)p->addr;
+                                ret = 1;
+                        } else {
+                                /* We have reentered the kprobe_handler(), since
+                                 * another probe was hit while within the
+                                 * handler. We here save the original kprobe
+                                 * variables and just single step on instruction
+                                 * of the new probe without calling any user
+                                 * handlers.
+                                 */
+                                save_previous_kprobe();
+                                set_current_kprobe(p, regs);
+                                p->nmissed++;
+                                prepare_singlestep(p, regs);
+                                kprobe_status = KPROBE_REENTER;
+                                return 1;
                         }
-                        disarm_kprobe(p, regs);
-                        ret = 1;
                 } else {
                         p = current_kprobe;
                         if (p->break_handler && p->break_handler(p, regs)) {
@@ -296,11 +395,7 @@ int kprobe_handler(struct pt_regs *regs)
         }
 
         kprobe_status = KPROBE_HIT_ACTIVE;
-        current_kprobe = p;
-        kprobe_saved_rflags = kprobe_old_rflags
-            = (regs->eflags & (TF_MASK | IF_MASK));
-        if (is_IF_modifier(p->ainsn.insn))
-                kprobe_saved_rflags &= ~IF_MASK;
+        set_current_kprobe(p, regs);
 
         if (p->pre_handler && p->pre_handler(p, regs))
                 /* handler has already set things up, so skip ss setup */
@@ -317,6 +412,55 @@ no_kprobe:
 }
 
 /*
+ * For function-return probes, init_kprobes() establishes a probepoint
+ * here. When a retprobed function returns, this probe is hit and
+ * trampoline_probe_handler() runs, calling the kretprobe's handler.
+ */
+ void kretprobe_trampoline_holder(void)
+ {
+        asm volatile (  ".global kretprobe_trampoline\n"
+                        "kretprobe_trampoline: \n"
+                        "nop\n");
+ }
+
+/*
+ * Called when we hit the probe point at kretprobe_trampoline
+ */
+int trampoline_probe_handler(struct kprobe *p, struct pt_regs *regs)
+{
+        struct task_struct *tsk;
+        struct kretprobe_instance *ri;
+        struct hlist_head *head;
+        struct hlist_node *node;
+        unsigned long *sara = (unsigned long *)regs->rsp - 1;
+
+        tsk = arch_get_kprobe_task(sara);
+        head = kretprobe_inst_table_head(tsk);
+
+        hlist_for_each_entry(ri, node, head, hlist) {
+                if (ri->stack_addr == sara && ri->rp) {
+                        if (ri->rp->handler)
+                                ri->rp->handler(ri, regs);
+                }
+        }
+        return 0;
+}
+
+void trampoline_post_handler(struct kprobe *p, struct pt_regs *regs,
+                                                unsigned long flags)
+{
+        struct kretprobe_instance *ri;
+        /* RA already popped */
+        unsigned long *sara = ((unsigned long *)regs->rsp) - 1;
+
+        while ((ri = get_rp_inst(sara))) {
+                regs->rip = (unsigned long)ri->ret_addr;
+                recycle_rp_inst(ri);
+        }
+        regs->eflags &= ~TF_MASK;
+}
+
+/*
  * Called after single-stepping.  p->addr is the address of the
  * instruction whose first byte has been replaced by the "int 3"
  * instruction.  To avoid the SMP problems that can occur when we
@@ -401,13 +545,23 @@ int post_kprobe_handler(struct pt_regs *regs)
         if (!kprobe_running())
                 return 0;
 
-        if (current_kprobe->post_handler)
+        if ((kprobe_status != KPROBE_REENTER) && current_kprobe->post_handler) {
+                kprobe_status = KPROBE_HIT_SSDONE;
                 current_kprobe->post_handler(current_kprobe, regs, 0);
+        }
 
-        resume_execution(current_kprobe, regs);
+        if (current_kprobe->post_handler != trampoline_post_handler)
+                resume_execution(current_kprobe, regs);
         regs->eflags |= kprobe_saved_rflags;
 
-        unlock_kprobes();
+        /* Restore the original saved kprobes variables and continue. */
+        if (kprobe_status == KPROBE_REENTER) {
+                restore_previous_kprobe();
+                goto out;
+        } else {
+                unlock_kprobes();
+        }
+out:
         preempt_enable_no_resched();
 
         /*
diff --git a/arch/x86_64/kernel/mpparse.c b/arch/x86_64/kernel/mpparse.c
index 61a63be6b294..9c5aa2a790c7 100644
--- a/arch/x86_64/kernel/mpparse.c
+++ b/arch/x86_64/kernel/mpparse.c
@@ -23,6 +23,7 @@
 #include <linux/kernel_stat.h>
 #include <linux/mc146818rtc.h>
 #include <linux/acpi.h>
+#include <linux/module.h>
 
 #include <asm/smp.h>
 #include <asm/mtrr.h>
@@ -45,7 +46,8 @@ int acpi_found_madt;
 int apic_version [MAX_APICS];
 unsigned char mp_bus_id_to_type [MAX_MP_BUSSES] = { [0 ... MAX_MP_BUSSES-1] = -1 };
 int mp_bus_id_to_pci_bus [MAX_MP_BUSSES] = { [0 ... MAX_MP_BUSSES-1] = -1 };
-cpumask_t pci_bus_to_cpumask [256] = { [0 ... 255] = CPU_MASK_ALL };
+unsigned char pci_bus_to_node [256];
+EXPORT_SYMBOL(pci_bus_to_node);
 
 static int mp_current_pci_id = 0;
 /* I/O APIC entries */
@@ -904,11 +906,20 @@ void __init mp_config_acpi_legacy_irqs (void)
         return;
 }
 
+#define MAX_GSI_NUM     4096
+
 int mp_register_gsi(u32 gsi, int edge_level, int active_high_low)
 {
         int                     ioapic = -1;
         int                     ioapic_pin = 0;
         int                     idx, bit = 0;
+        static int              pci_irq = 16;
+        /*
+         * Mapping between Global System Interrupts, which
+         * represent all possible interrupts, to the IRQs
+         * assigned to actual devices.
+         */
+        static int              gsi_to_irq[MAX_GSI_NUM];
 
         if (acpi_irq_model != ACPI_IRQ_MODEL_IOAPIC)
                 return gsi;
@@ -943,11 +954,21 @@ int mp_register_gsi(u32 gsi, int edge_level, int active_high_low)
         if ((1<<bit) & mp_ioapic_routing[ioapic].pin_programmed[idx]) {
                 Dprintk(KERN_DEBUG "Pin %d-%d already programmed\n",
                         mp_ioapic_routing[ioapic].apic_id, ioapic_pin);
-                return gsi;
+                return gsi_to_irq[gsi];
         }
 
         mp_ioapic_routing[ioapic].pin_programmed[idx] |= (1<<bit);
 
+        if (edge_level) {
+                /*
+                 * For PCI devices assign IRQs in order, avoiding gaps
+                 * due to unused I/O APIC pins.
+                 */
+                int irq = gsi;
+                gsi = pci_irq++;
+                gsi_to_irq[irq] = gsi;
+        }
+
         io_apic_set_pci_routing(ioapic, ioapic_pin, gsi,
                 edge_level == ACPI_EDGE_SENSITIVE ? 0 : 1,
                 active_high_low == ACPI_ACTIVE_HIGH ? 0 : 1);
diff --git a/arch/x86_64/kernel/process.c b/arch/x86_64/kernel/process.c
index dce8bab4306c..e59d1f9d6163 100644
--- a/arch/x86_64/kernel/process.c
+++ b/arch/x86_64/kernel/process.c
@@ -34,6 +34,7 @@
 #include <linux/ptrace.h>
 #include <linux/utsname.h>
 #include <linux/random.h>
+#include <linux/kprobes.h>
 
 #include <asm/uaccess.h>
 #include <asm/pgtable.h>
@@ -293,6 +294,14 @@ void exit_thread(void)
 {
         struct task_struct *me = current;
         struct thread_struct *t = &me->thread;
+
+        /*
+         * Remove function-return probe instances associated with this task
+         * and put them back on the free list. Do not insert an exit probe for
+         * this function, it will be disabled by kprobe_flush_task if you do.
+         */
+        kprobe_flush_task(me);
+
         if (me->thread.io_bitmap_ptr) { 
                 struct tss_struct *tss = &per_cpu(init_tss, get_cpu());
 
@@ -312,6 +321,13 @@ void flush_thread(void)
         struct task_struct *tsk = current;
         struct thread_info *t = current_thread_info();
 
+        /*
+         * Remove function-return probe instances associated with this task
+         * and put them back on the free list. Do not insert an exit probe for
+         * this function, it will be disabled by kprobe_flush_task if you do.
+         */
+        kprobe_flush_task(tsk);
+
         if (t->flags & _TIF_ABI_PENDING)
                 t->flags ^= (_TIF_ABI_PENDING | _TIF_IA32);
 
diff --git a/arch/x86_64/kernel/setup.c b/arch/x86_64/kernel/setup.c
index 99f038ede23c..000015dd5a8b 100644
--- a/arch/x86_64/kernel/setup.c
+++ b/arch/x86_64/kernel/setup.c
@@ -40,6 +40,8 @@
 #include <linux/acpi.h>
 #include <linux/kallsyms.h>
 #include <linux/edd.h>
+#include <linux/mmzone.h>
+
 #include <asm/mtrr.h>
 #include <asm/uaccess.h>
 #include <asm/system.h>
@@ -348,7 +350,7 @@ static __init void parse_cmdline_early (char ** cmdline_p)
                 if (!memcmp(from, "mem=", 4))
                         parse_memopt(from+4, &from); 
 
-#ifdef CONFIG_DISCONTIGMEM
+#ifdef CONFIG_NUMA
                 if (!memcmp(from, "numa=", 5))
                         numa_setup(from+5); 
 #endif
@@ -377,17 +379,20 @@ static __init void parse_cmdline_early (char ** cmdline_p)
         *cmdline_p = command_line;
 }
 
-#ifndef CONFIG_DISCONTIGMEM
-static void __init contig_initmem_init(void)
+#ifndef CONFIG_NUMA
+static void __init
+contig_initmem_init(unsigned long start_pfn, unsigned long end_pfn)
 {
-        unsigned long bootmap_size, bootmap; 
-        bootmap_size = bootmem_bootmap_pages(end_pfn)<<PAGE_SHIFT;
-        bootmap = find_e820_area(0, end_pfn<<PAGE_SHIFT, bootmap_size);
-        if (bootmap == -1L) 
-                panic("Cannot find bootmem map of size %ld\n",bootmap_size);
-        bootmap_size = init_bootmem(bootmap >> PAGE_SHIFT, end_pfn);
-        e820_bootmem_free(&contig_page_data, 0, end_pfn << PAGE_SHIFT); 
-        reserve_bootmem(bootmap, bootmap_size);
+        unsigned long bootmap_size, bootmap;
+
+        memory_present(0, start_pfn, end_pfn);
+        bootmap_size = bootmem_bootmap_pages(end_pfn)<<PAGE_SHIFT;
+        bootmap = find_e820_area(0, end_pfn<<PAGE_SHIFT, bootmap_size);
+        if (bootmap == -1L)
+                panic("Cannot find bootmem map of size %ld\n",bootmap_size);
+        bootmap_size = init_bootmem(bootmap >> PAGE_SHIFT, end_pfn);
+        e820_bootmem_free(NODE_DATA(0), 0, end_pfn << PAGE_SHIFT);
+        reserve_bootmem(bootmap, bootmap_size);
 } 
 #endif
 
@@ -554,10 +559,10 @@ void __init setup_arch(char **cmdline_p)
         acpi_numa_init();
 #endif
 
-#ifdef CONFIG_DISCONTIGMEM
+#ifdef CONFIG_NUMA
         numa_initmem_init(0, end_pfn); 
 #else
-        contig_initmem_init(); 
+        contig_initmem_init(0, end_pfn);
 #endif
 
         /* Reserve direct mapping */
@@ -618,6 +623,8 @@ void __init setup_arch(char **cmdline_p)
                 }
         }
 #endif
+
+        sparse_init();
         paging_init();
 
         check_ioapic();
diff --git a/arch/x86_64/kernel/signal.c b/arch/x86_64/kernel/signal.c
index 429c0269dc4e..98b7ba95d581 100644
--- a/arch/x86_64/kernel/signal.c
+++ b/arch/x86_64/kernel/signal.c
@@ -34,9 +34,9 @@
 
 #define _BLOCKABLE (~(sigmask(SIGKILL) | sigmask(SIGSTOP)))
 
-void ia32_setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info,
+int ia32_setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info,
                sigset_t *set, struct pt_regs * regs); 
-void ia32_setup_frame(int sig, struct k_sigaction *ka,
+int ia32_setup_frame(int sig, struct k_sigaction *ka,
             sigset_t *set, struct pt_regs * regs); 
 
 asmlinkage long
@@ -238,7 +238,7 @@ get_stack(struct k_sigaction *ka, struct pt_regs *regs, unsigned long size)
         return (void __user *)round_down(rsp - size, 16); 
 }
 
-static void setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info,
+static int setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info,
                            sigset_t *set, struct pt_regs * regs)
 {
         struct rt_sigframe __user *frame;
@@ -327,20 +327,23 @@ static void setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info,
                 current->comm, current->pid, frame, regs->rip, frame->pretcode);
 #endif
 
-        return;
+        return 1;
 
 give_sigsegv:
         force_sigsegv(sig, current);
+        return 0;
 }
 
 /*
  * OK, we're invoking a handler
  */     
 
-static void
+static int
 handle_signal(unsigned long sig, siginfo_t *info, struct k_sigaction *ka,
                 sigset_t *oldset, struct pt_regs *regs)
 {
+        int ret;
+
 #ifdef DEBUG_SIG
         printk("handle_signal pid:%d sig:%lu rip:%lx rsp:%lx regs=%p\n",
                 current->pid, sig,
@@ -384,20 +387,22 @@ handle_signal(unsigned long sig, siginfo_t *info, struct k_sigaction *ka,
 #ifdef CONFIG_IA32_EMULATION
         if (test_thread_flag(TIF_IA32)) {
                 if (ka->sa.sa_flags & SA_SIGINFO)
-                        ia32_setup_rt_frame(sig, ka, info, oldset, regs);
+                        ret = ia32_setup_rt_frame(sig, ka, info, oldset, regs);
                 else
-                        ia32_setup_frame(sig, ka, oldset, regs);
+                        ret = ia32_setup_frame(sig, ka, oldset, regs);
         } else 
 #endif
-        setup_rt_frame(sig, ka, info, oldset, regs);
+        ret = setup_rt_frame(sig, ka, info, oldset, regs);
 
-        if (!(ka->sa.sa_flags & SA_NODEFER)) {
+        if (ret && !(ka->sa.sa_flags & SA_NODEFER)) {
                 spin_lock_irq(&current->sighand->siglock);
                 sigorsets(&current->blocked,&current->blocked,&ka->sa.sa_mask);
                 sigaddset(&current->blocked,sig);
                 recalc_sigpending();
                 spin_unlock_irq(&current->sighand->siglock);
         }
+
+        return ret;
 }
 
 /*
@@ -417,7 +422,7 @@ int do_signal(struct pt_regs *regs, sigset_t *oldset)
          * kernel mode. Just return without doing anything
          * if so.
          */
-        if ((regs->cs & 3) != 3)
+        if (!user_mode(regs))
                 return 1;
 
         if (try_to_freeze(0))
@@ -434,11 +439,10 @@ int do_signal(struct pt_regs *regs, sigset_t *oldset)
                  * inside the kernel.
                  */
                 if (current->thread.debugreg7)
-                        asm volatile("movq %0,%%db7"    : : "r" (current->thread.debugreg7));
+                        set_debugreg(current->thread.debugreg7, 7);
 
                 /* Whee!  Actually deliver the signal.  */
-                handle_signal(signr, &info, &ka, oldset, regs);
-                return 1;
+                return handle_signal(signr, &info, &ka, oldset, regs);
         }
 
  no_signal:
diff --git a/arch/x86_64/kernel/time.c b/arch/x86_64/kernel/time.c
index fb8c809b4cd9..66bf6ddeb0c3 100644
--- a/arch/x86_64/kernel/time.c
+++ b/arch/x86_64/kernel/time.c
@@ -64,6 +64,7 @@ static int notsc __initdata = 0;
 unsigned int cpu_khz;                                   /* TSC clocks / usec, not used here */
 static unsigned long hpet_period;                       /* fsecs / HPET clock */
 unsigned long hpet_tick;                                /* HPET clocks / interrupt */
+static int hpet_use_timer;
 unsigned long vxtime_hz = PIT_TICK_RATE;
 int report_lost_ticks;                          /* command line option */
 unsigned long long monotonic_base;
@@ -105,7 +106,9 @@ static inline unsigned int do_gettimeoffset_tsc(void)
 
 static inline unsigned int do_gettimeoffset_hpet(void)
 {
-        return ((hpet_readl(HPET_COUNTER) - vxtime.last) * vxtime.quot) >> 32;
+        /* cap counter read to one tick to avoid inconsistencies */
+        unsigned long counter = hpet_readl(HPET_COUNTER) - vxtime.last;
+        return (min(counter,hpet_tick) * vxtime.quot) >> 32;
 }
 
 unsigned int (*do_gettimeoffset)(void) = do_gettimeoffset_tsc;
@@ -301,7 +304,7 @@ unsigned long long monotonic_clock(void)
 
                         last_offset = vxtime.last;
                         base = monotonic_base;
-                        this_offset = hpet_readl(HPET_T0_CMP) - hpet_tick;
+                        this_offset = hpet_readl(HPET_COUNTER);
 
                 } while (read_seqretry(&xtime_lock, seq));
                 offset = (this_offset - last_offset);
@@ -377,7 +380,14 @@ static irqreturn_t timer_interrupt(int irq, void *dev_id, struct pt_regs *regs)
 
         write_seqlock(&xtime_lock);
 
-        if (vxtime.hpet_address) {
+        if (vxtime.hpet_address)
+                offset = hpet_readl(HPET_COUNTER);
+
+        if (hpet_use_timer) {
+                /* if we're using the hpet timer functionality,
+                 * we can more accurately know the counter value
+                 * when the timer interrupt occured.
+                 */
                 offset = hpet_readl(HPET_T0_CMP) - hpet_tick;
                 delay = hpet_readl(HPET_COUNTER) - offset;
         } else {
@@ -803,17 +813,18 @@ static int hpet_timer_stop_set_go(unsigned long tick)
  * Set up timer 0, as periodic with first interrupt to happen at hpet_tick,
  * and period also hpet_tick.
  */
-
-        hpet_writel(HPET_TN_ENABLE | HPET_TN_PERIODIC | HPET_TN_SETVAL |
+        if (hpet_use_timer) {
+                hpet_writel(HPET_TN_ENABLE | HPET_TN_PERIODIC | HPET_TN_SETVAL |
                     HPET_TN_32BIT, HPET_T0_CFG);
-        hpet_writel(hpet_tick, HPET_T0_CMP);
-        hpet_writel(hpet_tick, HPET_T0_CMP); /* AK: why twice? */
-
+                hpet_writel(hpet_tick, HPET_T0_CMP);
+                hpet_writel(hpet_tick, HPET_T0_CMP); /* AK: why twice? */
+                cfg |= HPET_CFG_LEGACY;
+        }
 /*
  * Go!
  */
 
-        cfg |= HPET_CFG_ENABLE | HPET_CFG_LEGACY;
+        cfg |= HPET_CFG_ENABLE;
         hpet_writel(cfg, HPET_CFG);
 
         return 0;
@@ -834,8 +845,7 @@ static int hpet_init(void)
 
         id = hpet_readl(HPET_ID);
 
-        if (!(id & HPET_ID_VENDOR) || !(id & HPET_ID_NUMBER) ||
-            !(id & HPET_ID_LEGSUP))
+        if (!(id & HPET_ID_VENDOR) || !(id & HPET_ID_NUMBER))
                 return -1;
 
         hpet_period = hpet_readl(HPET_PERIOD);
@@ -845,6 +855,8 @@ static int hpet_init(void)
         hpet_tick = (1000000000L * (USEC_PER_SEC / HZ) + hpet_period / 2) /
                 hpet_period;
 
+        hpet_use_timer = (id & HPET_ID_LEGSUP);
+
         return hpet_timer_stop_set_go(hpet_tick);
 }
 
@@ -901,9 +913,11 @@ void __init time_init(void)
         set_normalized_timespec(&wall_to_monotonic,
                                 -xtime.tv_sec, -xtime.tv_nsec);
 
-        if (!hpet_init()) {
+        if (!hpet_init())
                 vxtime_hz = (1000000000000000L + hpet_period / 2) /
                         hpet_period;
+
+        if (hpet_use_timer) {
                 cpu_khz = hpet_calibrate_tsc();
                 timename = "HPET";
 #ifdef CONFIG_X86_PM_TIMER
@@ -968,7 +982,7 @@ void __init time_init_gtod(void)
         if (unsynchronized_tsc())
                 notsc = 1;
         if (vxtime.hpet_address && notsc) {
-                timetype = "HPET";
+                timetype = hpet_use_timer ? "HPET" : "PIT/HPET";
                 vxtime.last = hpet_readl(HPET_T0_CMP) - hpet_tick;
                 vxtime.mode = VXTIME_HPET;
                 do_gettimeoffset = do_gettimeoffset_hpet;
@@ -983,7 +997,7 @@ void __init time_init_gtod(void)
                 printk(KERN_INFO "Disabling vsyscall due to use of PM timer\n");
 #endif
         } else {
-                timetype = vxtime.hpet_address ? "HPET/TSC" : "PIT/TSC";
+                timetype = hpet_use_timer ? "HPET/TSC" : "PIT/TSC";
                 vxtime.mode = VXTIME_TSC;
         }
 
diff --git a/arch/x86_64/kernel/traps.c b/arch/x86_64/kernel/traps.c
index 3dfec8fdabcd..121646fc43f6 100644
--- a/arch/x86_64/kernel/traps.c
+++ b/arch/x86_64/kernel/traps.c
@@ -274,7 +274,7 @@ EXPORT_SYMBOL(dump_stack);
 void show_registers(struct pt_regs *regs)
 {
         int i;
-        int in_kernel = (regs->cs & 3) == 0;
+        int in_kernel = !user_mode(regs);
         unsigned long rsp;
         const int cpu = safe_smp_processor_id(); 
         struct task_struct *cur = cpu_pda[cpu].pcurrent; 
@@ -318,7 +318,7 @@ void handle_BUG(struct pt_regs *regs)
         struct bug_frame f;
         char tmp;
 
-        if (regs->cs & 3)
+        if (user_mode(regs))
                 return; 
         if (__copy_from_user(&f, (struct bug_frame *) regs->rip, 
                              sizeof(struct bug_frame)))
@@ -437,7 +437,7 @@ static void do_trap(int trapnr, int signr, char *str,
        }
 #endif
 
-        if ((regs->cs & 3)  != 0) { 
+        if (user_mode(regs)) {
                 struct task_struct *tsk = current;
 
                 if (exception_trace && unhandled_signal(tsk, signr))
@@ -522,7 +522,7 @@ asmlinkage void do_general_protection(struct pt_regs * regs, long error_code)
        }
 #endif
 
-        if ((regs->cs & 3)!=0) { 
+        if (user_mode(regs)) {
                 struct task_struct *tsk = current;
 
                 if (exception_trace && unhandled_signal(tsk, SIGSEGV))
@@ -638,7 +638,7 @@ asmlinkage struct pt_regs *sync_regs(struct pt_regs *eregs)
         if (eregs == (struct pt_regs *)eregs->rsp)
                 ;
         /* Exception from user space */
-        else if (eregs->cs & 3)
+        else if (user_mode(eregs))
                 regs = ((struct pt_regs *)current->thread.rsp0) - 1;
         /* Exception from kernel and interrupts are enabled. Move to
            kernel process stack. */
@@ -669,7 +669,7 @@ asmlinkage void do_debug(struct pt_regs * regs, unsigned long error_code)
        }
 #endif
 
-        asm("movq %%db6,%0" : "=r" (condition));
+        get_debugreg(condition, 6);
 
         if (notify_die(DIE_DEBUG, "debug", regs, condition, error_code,
                                                 SIGTRAP) == NOTIFY_STOP)
@@ -697,7 +697,7 @@ asmlinkage void do_debug(struct pt_regs * regs, unsigned long error_code)
                  * allowing programs to debug themselves without the ptrace()
                  * interface.
                  */
-                if ((regs->cs & 3) == 0)
+                if (!user_mode(regs))
                        goto clear_TF_reenable;
                 /*
                  * Was the TF flag set by a debugger? If so, clear it now,
@@ -715,13 +715,13 @@ asmlinkage void do_debug(struct pt_regs * regs, unsigned long error_code)
         info.si_signo = SIGTRAP;
         info.si_errno = 0;
         info.si_code = TRAP_BRKPT;
-        if ((regs->cs & 3) == 0) 
+        if (!user_mode(regs))
                 goto clear_dr7; 
 
         info.si_addr = (void __user *)regs->rip;
         force_sig_info(SIGTRAP, &info, tsk);    
 clear_dr7:
-        asm volatile("movq %0,%%db7"::"r"(0UL));
+        set_debugreg(0UL, 7);
         return;
 
 clear_TF_reenable:
@@ -756,7 +756,7 @@ asmlinkage void do_coprocessor_error(struct pt_regs *regs)
         unsigned short cwd, swd;
 
         conditional_sti(regs);
-        if ((regs->cs & 3) == 0 &&
+        if (!user_mode(regs) &&
             kernel_math_error(regs, "kernel x87 math error"))
                 return;
 
@@ -822,7 +822,7 @@ asmlinkage void do_simd_coprocessor_error(struct pt_regs *regs)
         unsigned short mxcsr;
 
         conditional_sti(regs);
-        if ((regs->cs & 3) == 0 &&
+        if (!user_mode(regs) &&
                 kernel_math_error(regs, "kernel simd math error"))
                 return;