Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull x86 fixes from Thomas Gleixner:
 "A set of small fixes:

   - make KGDB work again which got broken by the conversion of WARN()
     to #UD. The WARN fixup needs to run before the notifier callchain,
     otherwise KGDB tries to handle it and crashes.

   - disable KASAN in the ORC unwinder to prevent false positive KASAN
     warnings

   - prevent default mapping above 47bit when 5 level page tables are
     enabled

   - make the delay calibration optimization work correctly, which had
     the conditionals the wrong way around and was operating on data
     which was not yet updated.

   - remove the bogus X86_TRAP_BP trap init from the default IDT init
     table, which broke 32bit int3 handling by overwriting the correct
     int3 setup.

   - replace this_cpu* with boot_cpu_data access in the preemptible
     oprofile init code"

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/debug: Handle warnings before the notifier chain, to fix KGDB crash
  x86/mm: Fix ELF_ET_DYN_BASE for 5-level paging
  x86/idt: Remove X86_TRAP_BP initialization in idt_setup_traps()
  x86/oprofile/ppro: Do not use __this_cpu*() in preemptible context
  x86/unwind: Disable KASAN checking in the ORC unwinder
  x86/smpboot: Make optimization of delay calibration work correctly

7 files changed, 20 insertions, 19 deletions

diff --git a/arch/x86/include/asm/elf.h b/arch/x86/include/asm/elf.h
index c1a125e47ff3..3a091cea36c5 100644
--- a/arch/x86/include/asm/elf.h
+++ b/arch/x86/include/asm/elf.h
@@ -253,7 +253,7 @@ extern int force_personality32;
  * space open for things that want to use the area for 32-bit pointers.
  */
 #define ELF_ET_DYN_BASE         (mmap_is_ia32() ? 0x000400000UL : \
-                                                  (TASK_SIZE / 3 * 2))
+                                                  (DEFAULT_MAP_WINDOW / 3 * 2))
 
 /* This yields a mask that user programs can use to figure out what
    instruction set this CPU supports.  This could be done in user space,
diff --git a/arch/x86/kernel/idt.c b/arch/x86/kernel/idt.c
index 6107ee1cb8d5..014cb2fc47ff 100644
--- a/arch/x86/kernel/idt.c
+++ b/arch/x86/kernel/idt.c
@@ -92,8 +92,6 @@ static const __initdata struct idt_data def_idts[] = {
         INTG(X86_TRAP_DF,               double_fault),
 #endif
         INTG(X86_TRAP_DB,               debug),
-        INTG(X86_TRAP_NMI,              nmi),
-        INTG(X86_TRAP_BP,               int3),
 
 #ifdef CONFIG_X86_MCE
         INTG(X86_TRAP_MC,               &machine_check),
diff --git a/arch/x86/kernel/smpboot.c b/arch/x86/kernel/smpboot.c
index ad59edd84de7..65a0ccdc3050 100644
--- a/arch/x86/kernel/smpboot.c
+++ b/arch/x86/kernel/smpboot.c
@@ -194,6 +194,12 @@ static void smp_callin(void)
         smp_store_cpu_info(cpuid);
 
         /*
+         * The topology information must be up to date before
+         * calibrate_delay() and notify_cpu_starting().
+         */
+        set_cpu_sibling_map(raw_smp_processor_id());
+
+        /*
          * Get our bogomips.
          * Update loops_per_jiffy in cpu_data. Previous call to
          * smp_store_cpu_info() stored a value that is close but not as
@@ -203,11 +209,6 @@ static void smp_callin(void)
         cpu_data(cpuid).loops_per_jiffy = loops_per_jiffy;
         pr_debug("Stack at about %p\n", &cpuid);
 
-        /*
-         * This must be done before setting cpu_online_mask
-         * or calling notify_cpu_starting.
-         */
-        set_cpu_sibling_map(raw_smp_processor_id());
         wmb();
 
         notify_cpu_starting(cpuid);
diff --git a/arch/x86/kernel/traps.c b/arch/x86/kernel/traps.c
index 67db4f43309e..5a6b8f809792 100644
--- a/arch/x86/kernel/traps.c
+++ b/arch/x86/kernel/traps.c
@@ -209,9 +209,6 @@ do_trap_no_signal(struct task_struct *tsk, int trapnr, char *str,
                 if (fixup_exception(regs, trapnr))
                         return 0;
 
-                if (fixup_bug(regs, trapnr))
-                        return 0;
-
                 tsk->thread.error_code = error_code;
                 tsk->thread.trap_nr = trapnr;
                 die(str, regs, error_code);
@@ -292,6 +289,13 @@ static void do_error_trap(struct pt_regs *regs, long error_code, char *str,
 
         RCU_LOCKDEP_WARN(!rcu_is_watching(), "entry code didn't wake RCU");
 
+        /*
+         * WARN*()s end up here; fix them up before we call the
+         * notifier chain.
+         */
+        if (!user_mode(regs) && fixup_bug(regs, trapnr))
+                return;
+
         if (notify_die(DIE_TRAP, str, regs, error_code, trapnr, signr) !=
                         NOTIFY_STOP) {
                 cond_local_irq_enable(regs);
diff --git a/arch/x86/kernel/tsc.c b/arch/x86/kernel/tsc.c
index 796d96bb0821..ad2b925a808e 100644
--- a/arch/x86/kernel/tsc.c
+++ b/arch/x86/kernel/tsc.c
@@ -1346,12 +1346,10 @@ void __init tsc_init(void)
 unsigned long calibrate_delay_is_known(void)
 {
         int sibling, cpu = smp_processor_id();
-        struct cpumask *mask = topology_core_cpumask(cpu);
+        int constant_tsc = cpu_has(&cpu_data(cpu), X86_FEATURE_CONSTANT_TSC);
+        const struct cpumask *mask = topology_core_cpumask(cpu);
 
-        if (!tsc_disabled && !cpu_has(&cpu_data(cpu), X86_FEATURE_CONSTANT_TSC))
-                return 0;
-
-        if (!mask)
+        if (tsc_disabled || !constant_tsc || !mask)
                 return 0;
 
         sibling = cpumask_any_but(mask, cpu);
diff --git a/arch/x86/kernel/unwind_orc.c b/arch/x86/kernel/unwind_orc.c
index b95007e7c1b3..a3f973b2c97a 100644
--- a/arch/x86/kernel/unwind_orc.c
+++ b/arch/x86/kernel/unwind_orc.c
@@ -279,7 +279,7 @@ static bool deref_stack_reg(struct unwind_state *state, unsigned long addr,
         if (!stack_access_ok(state, addr, sizeof(long)))
                 return false;
 
-        *val = READ_ONCE_TASK_STACK(state->task, *(unsigned long *)addr);
+        *val = READ_ONCE_NOCHECK(*(unsigned long *)addr);
         return true;
 }
 
diff --git a/arch/x86/oprofile/op_model_ppro.c b/arch/x86/oprofile/op_model_ppro.c
index 350f7096baac..7913b6921959 100644
--- a/arch/x86/oprofile/op_model_ppro.c
+++ b/arch/x86/oprofile/op_model_ppro.c
@@ -212,8 +212,8 @@ static void arch_perfmon_setup_counters(void)
         eax.full = cpuid_eax(0xa);
 
         /* Workaround for BIOS bugs in 6/15. Taken from perfmon2 */
-        if (eax.split.version_id == 0 && __this_cpu_read(cpu_info.x86) == 6 &&
-                __this_cpu_read(cpu_info.x86_model) == 15) {
+        if (eax.split.version_id == 0 && boot_cpu_data.x86 == 6 &&
+            boot_cpu_data.x86_model == 15) {
                 eax.split.version_id = 2;
                 eax.split.num_counters = 2;
                 eax.split.bit_width = 40;