9 files changed, 40 insertions, 36 deletions

diff --git a/arch/x86/kernel/apic/io_apic.c b/arch/x86/kernel/apic/io_apic.c
index 84e33ff5a6d5..446702ed99dc 100644
--- a/arch/x86/kernel/apic/io_apic.c
+++ b/arch/x86/kernel/apic/io_apic.c
@@ -2588,8 +2588,8 @@ static struct resource * __init ioapic_setup_resources(void)
                 res[num].flags = IORESOURCE_MEM | IORESOURCE_BUSY;
                 snprintf(mem, IOAPIC_RESOURCE_NAME_SIZE, "IOAPIC %u", i);
                 mem += IOAPIC_RESOURCE_NAME_SIZE;
+                ioapics[i].iomem_res = &res[num];
                 num++;
-                ioapics[i].iomem_res = res;
         }
 
         ioapic_resources = res;
diff --git a/arch/x86/kernel/cpu/amd.c b/arch/x86/kernel/cpu/amd.c
index c343a54bed39..f5c69d8974e1 100644
--- a/arch/x86/kernel/cpu/amd.c
+++ b/arch/x86/kernel/cpu/amd.c
@@ -674,14 +674,14 @@ static void init_amd_bd(struct cpuinfo_x86 *c)
         u64 value;
 
         /* re-enable TopologyExtensions if switched off by BIOS */
-        if ((c->x86_model >= 0x10) && (c->x86_model <= 0x1f) &&
+        if ((c->x86_model >= 0x10) && (c->x86_model <= 0x6f) &&
             !cpu_has(c, X86_FEATURE_TOPOEXT)) {
 
                 if (msr_set_bit(0xc0011005, 54) > 0) {
                         rdmsrl(0xc0011005, value);
                         if (value & BIT_64(54)) {
                                 set_cpu_cap(c, X86_FEATURE_TOPOEXT);
-                                pr_info(FW_INFO "CPU: Re-enabling disabled Topology Extensions Support.\n");
+                                pr_info_once(FW_INFO "CPU: Re-enabling disabled Topology Extensions Support.\n");
                         }
                 }
         }
diff --git a/arch/x86/kernel/dumpstack.c b/arch/x86/kernel/dumpstack.c
index 2bb25c3fe2e8..ef8017ca5ba9 100644
--- a/arch/x86/kernel/dumpstack.c
+++ b/arch/x86/kernel/dumpstack.c
@@ -42,16 +42,14 @@ void printk_address(unsigned long address)
 static void
 print_ftrace_graph_addr(unsigned long addr, void *data,
                         const struct stacktrace_ops *ops,
-                        struct thread_info *tinfo, int *graph)
+                        struct task_struct *task, int *graph)
 {
-        struct task_struct *task;
         unsigned long ret_addr;
         int index;
 
         if (addr != (unsigned long)return_to_handler)
                 return;
 
-        task = tinfo->task;
         index = task->curr_ret_stack;
 
         if (!task->ret_stack || index < *graph)
@@ -68,7 +66,7 @@ print_ftrace_graph_addr(unsigned long addr, void *data,
 static inline void
 print_ftrace_graph_addr(unsigned long addr, void *data,
                         const struct stacktrace_ops *ops,
-                        struct thread_info *tinfo, int *graph)
+                        struct task_struct *task, int *graph)
 { }
 #endif
 
@@ -79,10 +77,10 @@ print_ftrace_graph_addr(unsigned long addr, void *data,
  * severe exception (double fault, nmi, stack fault, debug, mce) hardware stack
  */
 
-static inline int valid_stack_ptr(struct thread_info *tinfo,
+static inline int valid_stack_ptr(struct task_struct *task,
                         void *p, unsigned int size, void *end)
 {
-        void *t = tinfo;
+        void *t = task_stack_page(task);
         if (end) {
                 if (p < end && p >= (end-THREAD_SIZE))
                         return 1;
@@ -93,14 +91,14 @@ static inline int valid_stack_ptr(struct thread_info *tinfo,
 }
 
 unsigned long
-print_context_stack(struct thread_info *tinfo,
+print_context_stack(struct task_struct *task,
                 unsigned long *stack, unsigned long bp,
                 const struct stacktrace_ops *ops, void *data,
                 unsigned long *end, int *graph)
 {
         struct stack_frame *frame = (struct stack_frame *)bp;
 
-        while (valid_stack_ptr(tinfo, stack, sizeof(*stack), end)) {
+        while (valid_stack_ptr(task, stack, sizeof(*stack), end)) {
                 unsigned long addr;
 
                 addr = *stack;
@@ -112,7 +110,7 @@ print_context_stack(struct thread_info *tinfo,
                         } else {
                                 ops->address(data, addr, 0);
                         }
-                        print_ftrace_graph_addr(addr, data, ops, tinfo, graph);
+                        print_ftrace_graph_addr(addr, data, ops, task, graph);
                 }
                 stack++;
         }
@@ -121,7 +119,7 @@ print_context_stack(struct thread_info *tinfo,
 EXPORT_SYMBOL_GPL(print_context_stack);
 
 unsigned long
-print_context_stack_bp(struct thread_info *tinfo,
+print_context_stack_bp(struct task_struct *task,
                        unsigned long *stack, unsigned long bp,
                        const struct stacktrace_ops *ops, void *data,
                        unsigned long *end, int *graph)
@@ -129,7 +127,7 @@ print_context_stack_bp(struct thread_info *tinfo,
         struct stack_frame *frame = (struct stack_frame *)bp;
         unsigned long *ret_addr = &frame->return_address;
 
-        while (valid_stack_ptr(tinfo, ret_addr, sizeof(*ret_addr), end)) {
+        while (valid_stack_ptr(task, ret_addr, sizeof(*ret_addr), end)) {
                 unsigned long addr = *ret_addr;
 
                 if (!__kernel_text_address(addr))
@@ -139,7 +137,7 @@ print_context_stack_bp(struct thread_info *tinfo,
                         break;
                 frame = frame->next_frame;
                 ret_addr = &frame->return_address;
-                print_ftrace_graph_addr(addr, data, ops, tinfo, graph);
+                print_ftrace_graph_addr(addr, data, ops, task, graph);
         }
 
         return (unsigned long)frame;
diff --git a/arch/x86/kernel/dumpstack_32.c b/arch/x86/kernel/dumpstack_32.c
index 464ffd69b92e..fef917e79b9d 100644
--- a/arch/x86/kernel/dumpstack_32.c
+++ b/arch/x86/kernel/dumpstack_32.c
@@ -61,15 +61,13 @@ void dump_trace(struct task_struct *task, struct pt_regs *regs,
                 bp = stack_frame(task, regs);
 
         for (;;) {
-                struct thread_info *context;
                 void *end_stack;
 
                 end_stack = is_hardirq_stack(stack, cpu);
                 if (!end_stack)
                         end_stack = is_softirq_stack(stack, cpu);
 
-                context = task_thread_info(task);
-                bp = ops->walk_stack(context, stack, bp, ops, data,
+                bp = ops->walk_stack(task, stack, bp, ops, data,
                                      end_stack, &graph);
 
                 /* Stop if not on irq stack */
diff --git a/arch/x86/kernel/dumpstack_64.c b/arch/x86/kernel/dumpstack_64.c
index 5f1c6266eb30..d558a8a49016 100644
--- a/arch/x86/kernel/dumpstack_64.c
+++ b/arch/x86/kernel/dumpstack_64.c
@@ -153,7 +153,6 @@ void dump_trace(struct task_struct *task, struct pt_regs *regs,
                 const struct stacktrace_ops *ops, void *data)
 {
         const unsigned cpu = get_cpu();
-        struct thread_info *tinfo;
         unsigned long *irq_stack = (unsigned long *)per_cpu(irq_stack_ptr, cpu);
         unsigned long dummy;
         unsigned used = 0;
@@ -179,7 +178,6 @@ void dump_trace(struct task_struct *task, struct pt_regs *regs,
          * current stack address. If the stacks consist of nested
          * exceptions
          */
-        tinfo = task_thread_info(task);
         while (!done) {
                 unsigned long *stack_end;
                 enum stack_type stype;
@@ -202,7 +200,7 @@ void dump_trace(struct task_struct *task, struct pt_regs *regs,
                         if (ops->stack(data, id) < 0)
                                 break;
 
-                        bp = ops->walk_stack(tinfo, stack, bp, ops,
+                        bp = ops->walk_stack(task, stack, bp, ops,
                                              data, stack_end, &graph);
                         ops->stack(data, "<EOE>");
                         /*
@@ -218,7 +216,7 @@ void dump_trace(struct task_struct *task, struct pt_regs *regs,
 
                         if (ops->stack(data, "IRQ") < 0)
                                 break;
-                        bp = ops->walk_stack(tinfo, stack, bp,
+                        bp = ops->walk_stack(task, stack, bp,
                                      ops, data, stack_end, &graph);
                         /*
                          * We link to the next stack (which would be
@@ -240,7 +238,7 @@ void dump_trace(struct task_struct *task, struct pt_regs *regs,
         /*
          * This handles the process stack:
          */
-        bp = ops->walk_stack(tinfo, stack, bp, ops, data, NULL, &graph);
+        bp = ops->walk_stack(task, stack, bp, ops, data, NULL, &graph);
         put_cpu();
 }
 EXPORT_SYMBOL(dump_trace);
diff --git a/arch/x86/kernel/espfix_64.c b/arch/x86/kernel/espfix_64.c
index 4d38416e2a7f..04f89caef9c4 100644
--- a/arch/x86/kernel/espfix_64.c
+++ b/arch/x86/kernel/espfix_64.c
@@ -57,7 +57,7 @@
 # error "Need more than one PGD for the ESPFIX hack"
 #endif
 
-#define PGALLOC_GFP (GFP_KERNEL | __GFP_NOTRACK | __GFP_REPEAT | __GFP_ZERO)
+#define PGALLOC_GFP (GFP_KERNEL | __GFP_NOTRACK | __GFP_ZERO)
 
 /* This contains the *bottom* address of the espfix stack */
 DEFINE_PER_CPU_READ_MOSTLY(unsigned long, espfix_stack);
diff --git a/arch/x86/kernel/irq_32.c b/arch/x86/kernel/irq_32.c
index 38da8f29a9c8..c627bf8d98ad 100644
--- a/arch/x86/kernel/irq_32.c
+++ b/arch/x86/kernel/irq_32.c
@@ -130,11 +130,9 @@ void irq_ctx_init(int cpu)
 
 void do_softirq_own_stack(void)
 {
-        struct thread_info *curstk;
         struct irq_stack *irqstk;
         u32 *isp, *prev_esp;
 
-        curstk = current_stack();
         irqstk = __this_cpu_read(softirq_stack);
 
         /* build the stack frame on the softirq stack */
diff --git a/arch/x86/kernel/kprobes/core.c b/arch/x86/kernel/kprobes/core.c
index 38cf7a741250..7847e5c0e0b5 100644
--- a/arch/x86/kernel/kprobes/core.c
+++ b/arch/x86/kernel/kprobes/core.c
@@ -961,7 +961,19 @@ int kprobe_fault_handler(struct pt_regs *regs, int trapnr)
                  * normal page fault.
                  */
                 regs->ip = (unsigned long)cur->addr;
+                /*
+                 * Trap flag (TF) has been set here because this fault
+                 * happened where the single stepping will be done.
+                 * So clear it by resetting the current kprobe:
+                 */
+                regs->flags &= ~X86_EFLAGS_TF;
+
+                /*
+                 * If the TF flag was set before the kprobe hit,
+                 * don't touch it:
+                 */
                 regs->flags |= kcb->kprobe_old_flags;
+
                 if (kcb->kprobe_status == KPROBE_REENTER)
                         restore_previous_kprobe(kcb);
                 else
diff --git a/arch/x86/kernel/traps.c b/arch/x86/kernel/traps.c
index d1590486204a..00f03d82e69a 100644
--- a/arch/x86/kernel/traps.c
+++ b/arch/x86/kernel/traps.c
@@ -96,6 +96,12 @@ static inline void cond_local_irq_disable(struct pt_regs *regs)
                 local_irq_disable();
 }
 
+/*
+ * In IST context, we explicitly disable preemption.  This serves two
+ * purposes: it makes it much less likely that we would accidentally
+ * schedule in IST context and it will force a warning if we somehow
+ * manage to schedule by accident.
+ */
 void ist_enter(struct pt_regs *regs)
 {
         if (user_mode(regs)) {
@@ -110,13 +116,7 @@ void ist_enter(struct pt_regs *regs)
                 rcu_nmi_enter();
         }
 
-        /*
-         * We are atomic because we're on the IST stack; or we're on
-         * x86_32, in which case we still shouldn't schedule; or we're
-         * on x86_64 and entered from user mode, in which case we're
-         * still atomic unless ist_begin_non_atomic is called.
-         */
-        preempt_count_add(HARDIRQ_OFFSET);
+        preempt_disable();
 
         /* This code is a bit fragile.  Test it. */
         RCU_LOCKDEP_WARN(!rcu_is_watching(), "ist_enter didn't work");
@@ -124,7 +124,7 @@ void ist_enter(struct pt_regs *regs)
 
 void ist_exit(struct pt_regs *regs)
 {
-        preempt_count_sub(HARDIRQ_OFFSET);
+        preempt_enable_no_resched();
 
         if (!user_mode(regs))
                 rcu_nmi_exit();
@@ -155,7 +155,7 @@ void ist_begin_non_atomic(struct pt_regs *regs)
         BUG_ON((unsigned long)(current_top_of_stack() -
                                current_stack_pointer()) >= THREAD_SIZE);
 
-        preempt_count_sub(HARDIRQ_OFFSET);
+        preempt_enable_no_resched();
 }
 
 /**
@@ -165,7 +165,7 @@ void ist_begin_non_atomic(struct pt_regs *regs)
  */
 void ist_end_non_atomic(void)
 {
-        preempt_count_add(HARDIRQ_OFFSET);
+        preempt_disable();
 }
 
 static nokprobe_inline int