[tip: objtool/urgent] objtool: Fix Clang jump table detection

tip-bot2 for Josh Poimboeuf posted 1 patch 2 weeks, 5 days ago
There is a newer version of this series
tools/objtool/check.c | 5 ++---
1 file changed, 2 insertions(+), 3 deletions(-)
[tip: objtool/urgent] objtool: Fix Clang jump table detection
Posted by tip-bot2 for Josh Poimboeuf 2 weeks, 5 days ago
The following commit has been merged into the objtool/urgent branch of tip:

Commit-ID:     4e5019216402ad0b4a84cff457b662d26803f103
Gitweb:        https://git.kernel.org/tip/4e5019216402ad0b4a84cff457b662d26803f103
Author:        Josh Poimboeuf <jpoimboe@kernel.org>
AuthorDate:    Mon, 09 Mar 2026 09:03:05 -07:00
Committer:     Josh Poimboeuf <jpoimboe@kernel.org>
CommitterDate: Mon, 16 Mar 2026 15:31:25 -07:00

objtool: Fix Clang jump table detection

With Clang, there can be a conditional forward jump between the load of
the jump table address and the indirect branch.

Fixes the following warning:

  vmlinux.o: warning: objtool: ___bpf_prog_run+0x1c5: sibling call from callable instruction with modified stack frame

Reported-by: Arnd Bergmann <arnd@arndb.de>
Closes: https://lore.kernel.org/a426d669-58bb-4be1-9eaa-6f3d83109e2d@app.fastmail.com
Link: https://patch.msgid.link/7d8600caed08901b6679767488acd639f6df9688.1773071992.git.jpoimboe@kernel.org
Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
---
 tools/objtool/check.c | 5 ++---
 1 file changed, 2 insertions(+), 3 deletions(-)

diff --git a/tools/objtool/check.c b/tools/objtool/check.c
index 91b3ff4..b6765e8 100644
--- a/tools/objtool/check.c
+++ b/tools/objtool/check.c
@@ -2184,12 +2184,11 @@ static void mark_func_jump_tables(struct objtool_file *file,
 			last = insn;
 
 		/*
-		 * Store back-pointers for unconditional forward jumps such
+		 * Store back-pointers for forward jumps such
 		 * that find_jump_table() can back-track using those and
 		 * avoid some potentially confusing code.
 		 */
-		if (insn->type == INSN_JUMP_UNCONDITIONAL && insn->jump_dest &&
-		    insn->offset > last->offset &&
+		if (insn->jump_dest &&
 		    insn->jump_dest->offset > insn->offset &&
 		    !insn->jump_dest->first_jump_src) {