Merge tag 'perf-core-for-mingo-4.19-20180815' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux into perf/urgent

Pull perf/core improvements and fixes from Arnaldo Carvalho de Melo:

kernel:

- kallsyms, x86: Export addresses of PTI entry trampolines (Alexander Shishkin)

- kallsyms: Simplify update_iter_mod() (Adrian Hunter)

- x86: Add entry trampolines to kcore (Adrian Hunter)

Hardware tracing:

- Fix auxtrace queue resize (Adrian Hunter)

Arch specific:

- Fix uninitialized ARM SPE record error variable (Kim Phillips)

- Fix trace event post-processing in powerpc (Sandipan Das)

Build:

- Fix check-headers.sh AND list path of execution (Alexander Kapshuk)

- Remove -mcet and -fcf-protection when building the python binding
  with older clang versions (Arnaldo Carvalho de Melo)

- Make check-headers.sh check based on kernel dir (Jiri Olsa)

- Move syscall_64.tbl check into check-headers.sh (Jiri Olsa)

Infrastructure:

- Check for null when copying nsinfo.  (Benno Evers)

Libraries:

- Rename libtraceevent prefixes, prep work for making it a shared
  library generaly available (Tzvetomir Stoyanov (VMware))

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

arch/x86/mm/cpu_entry_area.c

@@ -2,6 +2,8 @@
 
 #include <linux/spinlock.h>
 #include <linux/percpu.h>
+#include <linux/kallsyms.h>
+#include <linux/kcore.h>
 
 #include <asm/cpu_entry_area.h>
 #include <asm/pgtable.h>
@@ -13,6 +15,7 @@ static DEFINE_PER_CPU_PAGE_ALIGNED(struct entry_stack_page, entry_stack_storage)
 #ifdef CONFIG_X86_64
 static DEFINE_PER_CPU_PAGE_ALIGNED(char, exception_stacks
 	[(N_EXCEPTION_STACKS - 1) * EXCEPTION_STKSZ + DEBUG_STKSZ]);
+static DEFINE_PER_CPU(struct kcore_list, kcore_entry_trampoline);
 #endif
 
 struct cpu_entry_area *get_cpu_entry_area(int cpu)
@@ -146,10 +149,40 @@ static void __init setup_cpu_entry_area(int cpu)
 
 	cea_set_pte(&get_cpu_entry_area(cpu)->entry_trampoline,
 		     __pa_symbol(_entry_trampoline), PAGE_KERNEL_RX);
+	/*
+	 * The cpu_entry_area alias addresses are not in the kernel binary
+	 * so they do not show up in /proc/kcore normally.  This adds entries
+	 * for them manually.
+	 */
+	kclist_add_remap(&per_cpu(kcore_entry_trampoline, cpu),
+			 _entry_trampoline,
+			 &get_cpu_entry_area(cpu)->entry_trampoline, PAGE_SIZE);
 #endif
 	percpu_setup_debug_store(cpu);
 }
 
+#ifdef CONFIG_X86_64
+int arch_get_kallsym(unsigned int symnum, unsigned long *value, char *type,
+		     char *name)
+{
+	unsigned int cpu, ncpu = 0;
+
+	if (symnum >= num_possible_cpus())
+		return -EINVAL;
+
+	for_each_possible_cpu(cpu) {
+		if (ncpu++ >= symnum)
+			break;
+	}
+
+	*value = (unsigned long)&get_cpu_entry_area(cpu)->entry_trampoline;
+	*type = 't';
+	strlcpy(name, "__entry_SYSCALL_64_trampoline", KSYM_NAME_LEN);
+
+	return 0;
+}
+#endif
+
 static __init void setup_cpu_entry_area_ptes(void)
 {
 #ifdef CONFIG_X86_32