Commit 08feafe8 authored by Josh Poimboeuf's avatar Josh Poimboeuf Committed by Peter Zijlstra
Browse files

objtool: Fix function fallthrough detection for vmlinux 



Objtool's function fallthrough detection only works on C objects.
The distinction between C and assembly objects no longer makes sense
with objtool running on vmlinux.o.

Now that copy_user_64.S has been fixed up, and an objtool sibling call
detection bug has been fixed, the asm code is in "compliance" and this
hack is no longer needed.  Remove it.

Fixes: ed53a0d9 ("x86/alternative: Use .ibt_endbr_seal to seal indirect calls")
Signed-off-by: default avatarJosh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: default avatarPeter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/b434cff98eca3a60dcc64c620d7d5d405a0f441c.1649718562.git.jpoimboe@redhat.com
parent 34c861e8

tools/objtool/check.c

+1 −1
Original line number Diff line number Diff line
@@ -3310,7 +3310,7 @@ static int validate_branch(struct objtool_file *file, struct symbol *func, 
	while (1) {

		next_insn = next_insn_to_validate(file, insn);



		if (file->c_file && func && insn->func && func != insn->func->pfunc) {

		if (func && insn->func && func != insn->func->pfunc) {

			WARN("%s() falls through to next function %s()",

			     func->name, insn->func->name);

			return 1;

tools/objtool/include/objtool/objtool.h

+1 −1
Original line number Diff line number Diff line
@@ -27,7 +27,7 @@ struct objtool_file { 
	struct list_head static_call_list;

	struct list_head mcount_loc_list;

	struct list_head endbr_list;

	bool ignore_unreachables, c_file, hints, rodata;

	bool ignore_unreachables, hints, rodata;



	unsigned int nr_endbr;

	unsigned int nr_endbr_int;

tools/objtool/objtool.c

+0 −1
Original line number Diff line number Diff line
@@ -129,7 +129,6 @@ struct objtool_file *objtool_open_read(const char *_objname) 
	INIT_LIST_HEAD(&file.static_call_list);

	INIT_LIST_HEAD(&file.mcount_loc_list);

	INIT_LIST_HEAD(&file.endbr_list);

	file.c_file = !vmlinux && find_section_by_name(file.elf, ".comment");

	file.ignore_unreachables = no_unreachable;

	file.hints = false;