Linus,

Please pull the latest core-urgent-for-linus git tree from:

   git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git 
core-urgent-for-linus

   # HEAD: a705e07b9c80df27b6bb12f7a4cd4cf4ed2f728b cpu/hotplug: Use distinct 
name for cpu_hotplug.dep_map

A CPU hotplug debuggability fix and three objtool false positive warnings fixes 
for new GCC6 code generation patterns.

 Thanks,

        Ingo

------------------>
Joonas Lahtinen (1):
      cpu/hotplug: Use distinct name for cpu_hotplug.dep_map

Josh Poimboeuf (3):
      objtool: Support '-mtune=atom' stack frame setup instruction
      objtool: Improve rare switch jump table pattern detection
      objtool: Skip all "unreachable instruction" warnings for gcov kernels


 kernel/cpu.c                    |  2 +-
 tools/objtool/arch/x86/decode.c |  9 ++++++
 tools/objtool/builtin-check.c   | 68 +++++++++++++++++++++--------------------
 3 files changed, 45 insertions(+), 34 deletions(-)

diff --git a/kernel/cpu.c b/kernel/cpu.c
index 5df20d6d1520..29de1a9352c0 100644
--- a/kernel/cpu.c
+++ b/kernel/cpu.c
@@ -228,7 +228,7 @@ static struct {
        .wq = __WAIT_QUEUE_HEAD_INITIALIZER(cpu_hotplug.wq),
        .lock = __MUTEX_INITIALIZER(cpu_hotplug.lock),
 #ifdef CONFIG_DEBUG_LOCK_ALLOC
-       .dep_map = {.name = "cpu_hotplug.lock" },
+       .dep_map = STATIC_LOCKDEP_MAP_INIT("cpu_hotplug.dep_map", 
&cpu_hotplug.dep_map),
 #endif
 };
 
diff --git a/tools/objtool/arch/x86/decode.c b/tools/objtool/arch/x86/decode.c
index c0c0b265e88e..b63a31be1218 100644
--- a/tools/objtool/arch/x86/decode.c
+++ b/tools/objtool/arch/x86/decode.c
@@ -98,6 +98,15 @@ int arch_decode_instruction(struct elf *elf, struct section 
*sec,
                        *type = INSN_FP_SETUP;
                break;
 
+       case 0x8d:
+               if (insn.rex_prefix.bytes &&
+                   insn.rex_prefix.bytes[0] == 0x48 &&
+                   insn.modrm.nbytes && insn.modrm.bytes[0] == 0x2c &&
+                   insn.sib.nbytes && insn.sib.bytes[0] == 0x24)
+                       /* lea %(rsp), %rbp */
+                       *type = INSN_FP_SETUP;
+               break;
+
        case 0x90:
                *type = INSN_NOP;
                break;
diff --git a/tools/objtool/builtin-check.c b/tools/objtool/builtin-check.c
index 143b6cdd7f06..4490601a9235 100644
--- a/tools/objtool/builtin-check.c
+++ b/tools/objtool/builtin-check.c
@@ -97,6 +97,19 @@ static struct instruction *next_insn_same_sec(struct 
objtool_file *file,
        return next;
 }
 
+static bool gcov_enabled(struct objtool_file *file)
+{
+       struct section *sec;
+       struct symbol *sym;
+
+       list_for_each_entry(sec, &file->elf->sections, list)
+               list_for_each_entry(sym, &sec->symbol_list, list)
+                       if (!strncmp(sym->name, "__gcov_.", 8))
+                               return true;
+
+       return false;
+}
+
 #define for_each_insn(file, insn)                                      \
        list_for_each_entry(insn, &file->insn_list, list)
 
@@ -713,6 +726,7 @@ static struct rela *find_switch_table(struct objtool_file 
*file,
                                      struct instruction *insn)
 {
        struct rela *text_rela, *rodata_rela;
+       struct instruction *orig_insn = insn;
 
        text_rela = find_rela_by_dest_range(insn->sec, insn->offset, insn->len);
        if (text_rela && text_rela->sym == file->rodata->sym) {
@@ -733,10 +747,16 @@ static struct rela *find_switch_table(struct objtool_file 
*file,
 
        /* case 3 */
        func_for_each_insn_continue_reverse(file, func, insn) {
-               if (insn->type == INSN_JUMP_UNCONDITIONAL ||
-                   insn->type == INSN_JUMP_DYNAMIC)
+               if (insn->type == INSN_JUMP_DYNAMIC)
                        break;
 
+               /* allow small jumps within the range */
+               if (insn->type == INSN_JUMP_UNCONDITIONAL &&
+                   insn->jump_dest &&
+                   (insn->jump_dest->offset <= insn->offset ||
+                    insn->jump_dest->offset >= orig_insn->offset))
+                   break;
+
                text_rela = find_rela_by_dest_range(insn->sec, insn->offset,
                                                    insn->len);
                if (text_rela && text_rela->sym == file->rodata->sym)
@@ -1034,34 +1054,6 @@ static int validate_branch(struct objtool_file *file,
        return 0;
 }
 
-static bool is_gcov_insn(struct instruction *insn)
-{
-       struct rela *rela;
-       struct section *sec;
-       struct symbol *sym;
-       unsigned long offset;
-
-       rela = find_rela_by_dest_range(insn->sec, insn->offset, insn->len);
-       if (!rela)
-               return false;
-
-       if (rela->sym->type != STT_SECTION)
-               return false;
-
-       sec = rela->sym->sec;
-       offset = rela->addend + insn->offset + insn->len - rela->offset;
-
-       list_for_each_entry(sym, &sec->symbol_list, list) {
-               if (sym->type != STT_OBJECT)
-                       continue;
-
-               if (offset >= sym->offset && offset < sym->offset + sym->len)
-                       return (!memcmp(sym->name, "__gcov0.", 8));
-       }
-
-       return false;
-}
-
 static bool is_kasan_insn(struct instruction *insn)
 {
        return (insn->type == INSN_CALL &&
@@ -1083,9 +1075,6 @@ static bool ignore_unreachable_insn(struct symbol *func,
        if (insn->type == INSN_NOP)
                return true;
 
-       if (is_gcov_insn(insn))
-               return true;
-
        /*
         * Check if this (or a subsequent) instruction is related to
         * CONFIG_UBSAN or CONFIG_KASAN.
@@ -1146,6 +1135,19 @@ static int validate_functions(struct objtool_file *file)
                                    ignore_unreachable_insn(func, insn))
                                        continue;
 
+                               /*
+                                * gcov produces a lot of unreachable
+                                * instructions.  If we get an unreachable
+                                * warning and the file has gcov enabled, just
+                                * ignore it, and all other such warnings for
+                                * the file.
+                                */
+                               if (!file->ignore_unreachables &&
+                                   gcov_enabled(file)) {
+                                       file->ignore_unreachables = true;
+                                       continue;
+                               }
+
                                WARN_FUNC("function has unreachable 
instruction", insn->sec, insn->offset);
                                warnings++;
                        }

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