From: Josh Poimboeuf <jpoimboe@xxxxxxxxxx> [ Upstream commit e6da9567959e164f82bc81967e0d5b10dee870b4 ] The ignore flag is set on fake jumps in order to keep add_jump_destinations() from setting their jump_dest, since it already got set when the fake jump was created. But using the ignore flag is a bit of a hack. It's normally used to skip validation of an instruction, which doesn't really make sense for fake jumps. Also, after the next patch, using the ignore flag for fake jumps can trigger a false "why am I validating an ignored function?" warning. Instead just add an explicit check in add_jump_destinations() to skip fake jumps. Signed-off-by: Josh Poimboeuf <jpoimboe@xxxxxxxxxx> Cc: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx> Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx> Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx> Link: http://lkml.kernel.org/r/71abc072ff48b2feccc197723a9c52859476c068.1557766718.git.jpoimboe@xxxxxxxxxx Signed-off-by: Ingo Molnar <mingo@xxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- tools/objtool/check.c | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-) diff --git a/tools/objtool/check.c b/tools/objtool/check.c index ae3446768181f..95326c6a7a249 100644 --- a/tools/objtool/check.c +++ b/tools/objtool/check.c @@ -28,6 +28,8 @@ #include <linux/hashtable.h> #include <linux/kernel.h> +#define FAKE_JUMP_OFFSET -1 + struct alternative { struct list_head list; struct instruction *insn; @@ -498,7 +500,7 @@ static int add_jump_destinations(struct objtool_file *file) insn->type != INSN_JUMP_UNCONDITIONAL) continue; - if (insn->ignore) + if (insn->ignore || insn->offset == FAKE_JUMP_OFFSET) continue; rela = find_rela_by_dest_range(insn->sec, insn->offset, @@ -645,10 +647,10 @@ static int handle_group_alt(struct objtool_file *file, clear_insn_state(&fake_jump->state); fake_jump->sec = special_alt->new_sec; - fake_jump->offset = -1; + fake_jump->offset = FAKE_JUMP_OFFSET; fake_jump->type = INSN_JUMP_UNCONDITIONAL; fake_jump->jump_dest = list_next_entry(last_orig_insn, list); - fake_jump->ignore = true; + fake_jump->func = orig_insn->func; } if (!special_alt->new_len) { -- 2.20.1
