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

Pull x86 cpu updates from Ingo Molnar:
 "Two changes:

   - Extend 32-bit double fault debugging aid to 64-bit
   - Fix a build warning"

* 'x86-cpu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/intel/cacheinfo: Shut up last long-standing warning
  x86: Extend #DF debugging aid to 64-bit

6 files changed, 45 insertions, 30 deletions

diff --git a/arch/x86/Kconfig.debug b/arch/x86/Kconfig.debug
index c198b7e13e7b..b6a770132b67 100644
--- a/arch/x86/Kconfig.debug
+++ b/arch/x86/Kconfig.debug
@@ -122,7 +122,6 @@ config DEBUG_NX_TEST
 config DOUBLEFAULT
         default y
         bool "Enable doublefault exception handler" if EXPERT
-        depends on X86_32
         ---help---
           This option allows trapping of rare doublefault exceptions that
           would otherwise cause a system to silently reboot. Disabling this
diff --git a/arch/x86/include/asm/processor.h b/arch/x86/include/asm/processor.h
index 22224b3b43bb..5b87d52eed0b 100644
--- a/arch/x86/include/asm/processor.h
+++ b/arch/x86/include/asm/processor.h
@@ -981,5 +981,5 @@ bool xen_set_default_idle(void);
 #endif
 
 void stop_this_cpu(void *dummy);
-
+void df_debug(struct pt_regs *regs, long error_code);
 #endif /* _ASM_X86_PROCESSOR_H */
diff --git a/arch/x86/kernel/Makefile b/arch/x86/kernel/Makefile
index 7bd3bd310106..4ce822ed58f5 100644
--- a/arch/x86/kernel/Makefile
+++ b/arch/x86/kernel/Makefile
@@ -67,7 +67,7 @@ obj-$(CONFIG_KEXEC)		+= relocate_kernel_$(BITS).o crash.o
 obj-$(CONFIG_CRASH_DUMP)        += crash_dump_$(BITS).o
 obj-y                           += kprobes/
 obj-$(CONFIG_MODULES)           += module.o
-obj-$(CONFIG_DOUBLEFAULT)       += doublefault_32.o
+obj-$(CONFIG_DOUBLEFAULT)       += doublefault.o
 obj-$(CONFIG_KGDB)              += kgdb.o
 obj-$(CONFIG_VM86)              += vm86_32.o
 obj-$(CONFIG_EARLY_PRINTK)      += early_printk.o
diff --git a/arch/x86/kernel/cpu/intel_cacheinfo.c b/arch/x86/kernel/cpu/intel_cacheinfo.c
index 7c6f7d548c0f..8dc72dda66fe 100644
--- a/arch/x86/kernel/cpu/intel_cacheinfo.c
+++ b/arch/x86/kernel/cpu/intel_cacheinfo.c
@@ -618,36 +618,34 @@ unsigned int __cpuinit init_intel_cacheinfo(struct cpuinfo_x86 *c)
                  * parameters cpuid leaf to find the cache details
                  */
                 for (i = 0; i < num_cache_leaves; i++) {
-                        struct _cpuid4_info_regs this_leaf;
+                        struct _cpuid4_info_regs this_leaf = {};
                         int retval;
 
                         retval = cpuid4_cache_lookup_regs(i, &this_leaf);
-                        if (retval >= 0) {
-                                switch (this_leaf.eax.split.level) {
-                                case 1:
-                                        if (this_leaf.eax.split.type ==
-                                                        CACHE_TYPE_DATA)
-                                                new_l1d = this_leaf.size/1024;
-                                        else if (this_leaf.eax.split.type ==
-                                                        CACHE_TYPE_INST)
-                                                new_l1i = this_leaf.size/1024;
-                                        break;
-                                case 2:
-                                        new_l2 = this_leaf.size/1024;
-                                        num_threads_sharing = 1 + this_leaf.eax.split.num_threads_sharing;
-                                        index_msb = get_count_order(num_threads_sharing);
-                                        l2_id = c->apicid & ~((1 << index_msb) - 1);
-                                        break;
-                                case 3:
-                                        new_l3 = this_leaf.size/1024;
-                                        num_threads_sharing = 1 + this_leaf.eax.split.num_threads_sharing;
-                                        index_msb = get_count_order(
-                                                        num_threads_sharing);
-                                        l3_id = c->apicid & ~((1 << index_msb) - 1);
-                                        break;
-                                default:
-                                        break;
-                                }
+                        if (retval < 0)
+                                continue;
+
+                        switch (this_leaf.eax.split.level) {
+                        case 1:
+                                if (this_leaf.eax.split.type == CACHE_TYPE_DATA)
+                                        new_l1d = this_leaf.size/1024;
+                                else if (this_leaf.eax.split.type == CACHE_TYPE_INST)
+                                        new_l1i = this_leaf.size/1024;
+                                break;
+                        case 2:
+                                new_l2 = this_leaf.size/1024;
+                                num_threads_sharing = 1 + this_leaf.eax.split.num_threads_sharing;
+                                index_msb = get_count_order(num_threads_sharing);
+                                l2_id = c->apicid & ~((1 << index_msb) - 1);
+                                break;
+                        case 3:
+                                new_l3 = this_leaf.size/1024;
+                                num_threads_sharing = 1 + this_leaf.eax.split.num_threads_sharing;
+                                index_msb = get_count_order(num_threads_sharing);
+                                l3_id = c->apicid & ~((1 << index_msb) - 1);
+                                break;
+                        default:
+                                break;
                         }
                 }
         }
diff --git a/arch/x86/kernel/doublefault_32.c b/arch/x86/kernel/doublefault.c
index 155a13f33ed8..5d3fe8d36e4a 100644
--- a/arch/x86/kernel/doublefault_32.c
+++ b/arch/x86/kernel/doublefault.c
@@ -9,6 +9,8 @@
 #include <asm/processor.h>
 #include <asm/desc.h>
 
+#ifdef CONFIG_X86_32
+
 #define DOUBLEFAULT_STACKSIZE (1024)
 static unsigned long doublefault_stack[DOUBLEFAULT_STACKSIZE];
 #define STACK_START (unsigned long)(doublefault_stack+DOUBLEFAULT_STACKSIZE)
@@ -67,3 +69,16 @@ struct tss_struct doublefault_tss __cacheline_aligned = {
                 .__cr3          = __pa_nodebug(swapper_pg_dir),
         }
 };
+
+/* dummy for do_double_fault() call */
+void df_debug(struct pt_regs *regs, long error_code) {}
+
+#else /* !CONFIG_X86_32 */
+
+void df_debug(struct pt_regs *regs, long error_code)
+{
+        pr_emerg("PANIC: double fault, error_code: 0x%lx\n", error_code);
+        show_regs(regs);
+        panic("Machine halted.");
+}
+#endif
diff --git a/arch/x86/kernel/traps.c b/arch/x86/kernel/traps.c
index 772e2a846dec..167d481c5fd3 100644
--- a/arch/x86/kernel/traps.c
+++ b/arch/x86/kernel/traps.c
@@ -254,6 +254,9 @@ dotraplinkage void do_double_fault(struct pt_regs *regs, long error_code)
         tsk->thread.error_code = error_code;
         tsk->thread.trap_nr = X86_TRAP_DF;
 
+#ifdef CONFIG_DOUBLEFAULT
+        df_debug(regs, error_code);
+#endif
         /*
          * This is always a kernel trap and never fixable (and thus must
          * never return).