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From: Josh Poimboeuf <jpoimboe@kernel.org>
To: x86@kernel.org
Cc: linux-kernel@vger.kernel.org, live-patching@vger.kernel.org,
	Peter Zijlstra <peterz@infradead.org>,
	Joe Lawrence <joe.lawrence@redhat.com>,
	Song Liu <song@kernel.org>,
	Catalin Marinas <catalin.marinas@arm.com>,
	Will Deacon <will@kernel.org>,
	linux-arm-kernel@lists.infradead.org,
	Mark Rutland <mark.rutland@arm.com>,
	Nathan Chancellor <nathan@kernel.org>,
	Nicolas Schier <nsc@kernel.org>,
	Herbert Xu <herbert@gondor.apana.org.au>
Subject: [PATCH 10/14] objtool: Ignore jumps to the end of the function for non-CFG arches
Date: Wed,  4 Mar 2026 19:31:29 -0800	[thread overview]
Message-ID: <4aaa59736860f593e18e5978ebd56e04e4deea9d.1772681234.git.jpoimboe@kernel.org> (raw)
In-Reply-To: <cover.1772681234.git.jpoimboe@kernel.org>

Sometimes Clang arm64 code jumps to the end of the function for UB.
No need to make that an error, arm64 doesn't reverse engineer the CFG
anyway.

Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
---
 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 f73cf1382e5c..23cde2de66b9 100644
--- a/tools/objtool/check.c
+++ b/tools/objtool/check.c
@@ -1630,10 +1630,12 @@ static int add_jump_destinations(struct objtool_file *file)
 			/*
 			 * GCOV/KCOV dead code can jump to the end of
 			 * the function/section.
+			 *
+			 * Clang on arm64 also does this sometimes for
+			 * undefined behavior.
 			 */
-			if (file->ignore_unreachables && func &&
-			    dest_sec == insn->sec &&
-			    dest_off == func->offset + func->len)
+			if ((file->ignore_unreachables || (!opts.stackval && !opts.orc)) &&
+			    func && dest_sec == insn->sec && dest_off == func->offset + func->len)
 				continue;
 
 			ERROR_INSN(insn, "can't find jump dest instruction at %s",
-- 
2.53.0


  parent reply	other threads:[~2026-03-05  3:31 UTC|newest]

Thread overview: 36+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2026-03-05  3:31 [PATCH 00/14] objtool/arm64: Port klp-build to arm64 Josh Poimboeuf
2026-03-05  3:31 ` [PATCH 01/14] objtool: Fix data alignment in elf_add_data() Josh Poimboeuf
2026-03-09 19:54   ` [tip: objtool/urgent] " tip-bot2 for Josh Poimboeuf
2026-03-05  3:31 ` [PATCH 02/14] objtool: Fix ERROR_INSN() error message Josh Poimboeuf
2026-03-09 19:54   ` [tip: objtool/urgent] " tip-bot2 for Josh Poimboeuf
2026-03-05  3:31 ` [PATCH 03/14] arm64: Annotate intra-function calls Josh Poimboeuf
2026-03-11 23:12   ` Song Liu
2026-03-05  3:31 ` [PATCH 04/14] arm64: head: Move boot header to .head.data Josh Poimboeuf
2026-03-11 23:12   ` Song Liu
2026-03-05  3:31 ` [PATCH 05/14] arm64: Fix EFI linking with -fdata-sections Josh Poimboeuf
2026-03-11 23:12   ` Song Liu
2026-03-05  3:31 ` [PATCH 06/14] crypto: arm64: Move data to .rodata Josh Poimboeuf
2026-03-05  3:31 ` [PATCH 07/14] objtool: Extricate checksum calculation from validate_branch() Josh Poimboeuf
2026-03-10 10:47   ` Miroslav Benes
2026-03-10 16:27     ` Josh Poimboeuf
2026-03-11  8:24       ` Miroslav Benes
2026-03-17 17:21         ` Josh Poimboeuf
2026-03-05  3:31 ` [PATCH 08/14] objtool: Allow setting --mnop without --mcount Josh Poimboeuf
2026-03-11 23:13   ` Song Liu
2026-03-05  3:31 ` [PATCH 09/14] kbuild: Only run objtool if there is at least one command Josh Poimboeuf
2026-03-14  0:45   ` Nathan Chancellor
2026-03-05  3:31 ` Josh Poimboeuf [this message]
2026-03-11 23:14   ` [PATCH 10/14] objtool: Ignore jumps to the end of the function for non-CFG arches Song Liu
2026-03-05  3:31 ` [PATCH 11/14] objtool: Allow empty alternatives Josh Poimboeuf
2026-03-11 23:14   ` Song Liu
2026-03-05  3:31 ` [PATCH 12/14] objtool: Reuse consecutive string references Josh Poimboeuf
2026-03-11 23:15   ` Song Liu
2026-03-05  3:31 ` [PATCH 13/14] objtool: Introduce objtool for arm64 Josh Poimboeuf
2026-03-05  3:31 ` [PATCH 14/14] klp-build: Support cross-compilation Josh Poimboeuf
2026-03-11 23:18   ` Song Liu
2026-03-16 19:15     ` Josh Poimboeuf
2026-03-17 17:52       ` Josh Poimboeuf
2026-03-17 18:21         ` Song Liu
2026-03-17 18:53           ` Josh Poimboeuf
2026-03-17 18:58             ` Song Liu
2026-03-11 23:23 ` [PATCH 00/14] objtool/arm64: Port klp-build to arm64 Song Liu

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