objtool: Add abstraction for destination offsets

The jump and call destination relocation offsets are x86-specific.
Abstract them by calling arch-specific implementations.

[ jthierry: Remove superfluous comment; replace other addend offsets
      	    with arch_dest_rela_offset() ]

Signed-off-by: Raphael Gault <raphael.gault@arm.com>
Signed-off-by: Julien Thierry <jthierry@redhat.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Miroslav Benes <mbenes@suse.cz>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>

diff --git a/tools/objtool/arch.h b/tools/objtool/arch.h
index ced3765..a9a50a2 100644 (file)
--- a/tools/objtool/arch.h
+++ b/tools/objtool/arch.h
@@ -66,6 +66,8 @@ struct stack_op {
        struct op_src src;
 };
 
+struct instruction;
+
 void arch_initial_func_cfi_state(struct cfi_state *state);
 
 int arch_decode_instruction(struct elf *elf, struct section *sec,
@@ -75,4 +77,8 @@ int arch_decode_instruction(struct elf *elf, struct section *sec,
 
 bool arch_callee_saved_reg(unsigned char reg);
 
+unsigned long arch_jump_destination(struct instruction *insn);
+
+unsigned long arch_dest_rela_offset(int addend);
+
 #endif /* _ARCH_H */

diff --git a/tools/objtool/arch/x86/decode.c b/tools/objtool/arch/x86/decode.c
index a62e032..7ce8650 100644 (file)
--- a/tools/objtool/arch/x86/decode.c
+++ b/tools/objtool/arch/x86/decode.c
@@ -11,6 +11,7 @@
 #include "../../../arch/x86/lib/inat.c"
 #include "../../../arch/x86/lib/insn.c"
 
+#include "../../check.h"
 #include "../../elf.h"
 #include "../../arch.h"
 #include "../../warn.h"
@@ -66,6 +67,16 @@ bool arch_callee_saved_reg(unsigned char reg)
        }
 }
 
+unsigned long arch_dest_rela_offset(int addend)
+{
+       return addend + 4;
+}
+
+unsigned long arch_jump_destination(struct instruction *insn)
+{
+       return insn->offset + insn->len + insn->immediate;
+}
+
 int arch_decode_instruction(struct elf *elf, struct section *sec,
                            unsigned long offset, unsigned int maxlen,
                            unsigned int *len, enum insn_type *type,

diff --git a/tools/objtool/check.c b/tools/objtool/check.c
index 229d61e..cffa5e3 100644 (file)
--- a/tools/objtool/check.c
+++ b/tools/objtool/check.c
@@ -574,13 +574,14 @@ static int add_jump_destinations(struct objtool_file *file)
                                               insn->offset, insn->len);
                if (!rela) {
                        dest_sec = insn->sec;
-                       dest_off = insn->offset + insn->len + insn->immediate;
+                       dest_off = arch_jump_destination(insn);
                } else if (rela->sym->type == STT_SECTION) {
                        dest_sec = rela->sym->sec;
-                       dest_off = rela->addend + 4;
+                       dest_off = arch_dest_rela_offset(rela->addend);
                } else if (rela->sym->sec->idx) {
                        dest_sec = rela->sym->sec;
-                       dest_off = rela->sym->sym.st_value + rela->addend + 4;
+                       dest_off = rela->sym->sym.st_value +
+                                  arch_dest_rela_offset(rela->addend);
                } else if (strstr(rela->sym->name, "_indirect_thunk_")) {
                        /*
                         * Retpoline jumps are really dynamic jumps in
@@ -670,7 +671,7 @@ static int add_call_destinations(struct objtool_file *file)
                rela = find_rela_by_dest_range(file->elf, insn->sec,
                                               insn->offset, insn->len);
                if (!rela) {
-                       dest_off = insn->offset + insn->len + insn->immediate;
+                       dest_off = arch_jump_destination(insn);
                        insn->call_dest = find_func_by_offset(insn->sec, dest_off);
                        if (!insn->call_dest)
                                insn->call_dest = find_symbol_by_offset(insn->sec, dest_off);
@@ -693,13 +694,14 @@ static int add_call_destinations(struct objtool_file *file)
                        }
 
                } else if (rela->sym->type == STT_SECTION) {
+                       dest_off = arch_dest_rela_offset(rela->addend);
                        insn->call_dest = find_func_by_offset(rela->sym->sec,
-                                                             rela->addend+4);
+                                                             dest_off);
                        if (!insn->call_dest) {
-                               WARN_FUNC("can't find call dest symbol at %s+0x%x",
+                               WARN_FUNC("can't find call dest symbol at %s+0x%lx",
                                          insn->sec, insn->offset,
                                          rela->sym->sec->name,
-                                         rela->addend + 4);
+                                         dest_off);
                                return -1;
                        }
                } else
@@ -810,7 +812,7 @@ static int handle_group_alt(struct objtool_file *file,
                if (!insn->immediate)
                        continue;
 
-               dest_off = insn->offset + insn->len + insn->immediate;
+               dest_off = arch_jump_destination(insn);
                if (dest_off == special_alt->new_off + special_alt->new_len) {
                        if (!fake_jump) {
                                WARN("%s: alternative jump to end of section",