From nobody Sat Jun 13 22:19:44 2026 Received: from galois.linutronix.de (Galois.linutronix.de [193.142.43.55]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 1EB40480334; Tue, 5 May 2026 10:56:36 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=193.142.43.55 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1777978597; cv=none; b=i0Ok7GJLxZwANW3po20PPlM/v/VbD9wYb+onU7XUyRioMXugwWDXFr8wPYco7cIREG7gKK8MdWkzER1XYNIB8uTKgQXROJn7/UApbC+HumqxRqcN/+Jrv22qVpQF7DoG9wX9WVGJ6S9u2WYrDvKwpxqlGS9YwrAApT+QbSuL5r4= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1777978597; c=relaxed/simple; bh=aPxHyLtIYF+Y/GzF5BrUpyEzhVCb6vhF2aCVEXSalT0=; h=Date:From:To:Subject:Cc:MIME-Version:Message-ID:Content-Type; b=dHC06EYkPA8XriQhScq32EnlSVJ8Z9jNbe5gV38Xnoqq0KZApoG9+H4DD/SPQYU2WhDw3megOInS7GnBW5PEOmAAkPbkS6HXA9jDQkF+NafyBlSaWBT93Xa3aEGjzegD7UZBYKnM714ew8BiXyyegW2LAxRj/MThOdq6JiFatBU= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linutronix.de; spf=pass smtp.mailfrom=linutronix.de; dkim=pass (2048-bit key) header.d=linutronix.de header.i=@linutronix.de header.b=Xehs0cvR; dkim=permerror (0-bit key) header.d=linutronix.de header.i=@linutronix.de header.b=FZPkTvbK; arc=none smtp.client-ip=193.142.43.55 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linutronix.de Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linutronix.de Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=linutronix.de header.i=@linutronix.de header.b="Xehs0cvR"; dkim=permerror (0-bit key) header.d=linutronix.de header.i=@linutronix.de header.b="FZPkTvbK" Date: Tue, 05 May 2026 10:56:33 -0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1777978594; h=from:from:sender:sender:reply-to:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding; bh=Jrz1G+aFB7PmBNa9dmB2ZV2eUZf6+iTVhfVO7utSGys=; b=Xehs0cvRrYjjSyL9lBfpAI5t5m3jMg8s+Z3eWWDiajTaMqEYoNKLhdmZYu+W1QnIMIN/LY rtcLuwRALRCMPBPaPFw+4+zmDSGmfiwbV2IR45s3oO91ELZiHs/IfjSdrSgx9rEzKqFlwB QWu8TWA5STmaJWjf5NGTC5Lj80DkulcCYBs/hQG3amB+mKdh2RilmCm62rvAm4Izv51xt0 awlVoZMGeaehbfZPmgkmACkmtBCQW+j+E00KlbFAiroaA1meEm9NyiZmylm9ydc+UwE4Z9 54y8biHqc0tT8BCF5tGczM6wnxr/+08uq62DAGczFHBmxqRGrq8CDYSo8scVMA== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1777978594; h=from:from:sender:sender:reply-to:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding; bh=Jrz1G+aFB7PmBNa9dmB2ZV2eUZf6+iTVhfVO7utSGys=; b=FZPkTvbK8wRgC7j5r3bacNEwo1HUTYvP2SsGY/dHnPFQMIbSLfDvQoWL+sVXM/O8okq9pE 7GZNBiekzcnTKYAA== From: "tip-bot2 for Josh Poimboeuf" Sender: tip-bot2@linutronix.de Reply-to: linux-kernel@vger.kernel.org To: linux-tip-commits@vger.kernel.org Subject: [tip: objtool/core] objtool/klp: Simplify reloc symbol conversion Cc: Song Liu , Miroslav Benes , Josh Poimboeuf , x86@kernel.org, linux-kernel@vger.kernel.org Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Message-ID: <177797859346.424702.4038329861070564035.tip-bot2@tip-bot2> Robot-ID: Robot-Unsubscribe: Contact to get blacklisted from these emails Precedence: bulk Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable The following commit has been merged into the objtool/core branch of tip: Commit-ID: 8fdc3585b3b09f2c55d8573edc6a1dbfeb728f03 Gitweb: https://git.kernel.org/tip/8fdc3585b3b09f2c55d8573edc6a1dbfe= b728f03 Author: Josh Poimboeuf AuthorDate: Wed, 29 Apr 2026 20:07:28 -07:00 Committer: Josh Poimboeuf CommitterDate: Mon, 04 May 2026 21:16:01 -07:00 objtool/klp: Simplify reloc symbol conversion Inline section_reference_needed() and is_reloc_allowed() into convert_reloc_sym() and remove the redundant is_reloc_allowed() check in clone_reloc(). Move the is_sec_sym() checks into the convert callees so they become no-ops when the reloc is already in the right format. This allows convert_reloc_sym() to unconditionally dispatch to the right converter based on section type. Acked-by: Song Liu Reviewed-by: Miroslav Benes Signed-off-by: Josh Poimboeuf --- tools/objtool/klp-diff.c | 76 ++++++++++++++------------------------- 1 file changed, 28 insertions(+), 48 deletions(-) diff --git a/tools/objtool/klp-diff.c b/tools/objtool/klp-diff.c index 19bc811..78633c9 100644 --- a/tools/objtool/klp-diff.c +++ b/tools/objtool/klp-diff.c @@ -838,39 +838,6 @@ static int clone_included_functions(struct elfs *e) return 0; } =20 -/* - * Determine whether a relocation should reference the section rather than= the - * underlying symbol. - */ -static bool section_reference_needed(struct section *sec) -{ - /* - * String symbols are zero-length and uncorrelated. It's easier to - * deal with them as section symbols. - */ - if (is_string_sec(sec)) - return true; - - /* - * .rodata has mostly anonymous data so there's no way to determine the - * length of a needed reference. just copy the whole section if needed. - */ - if (strstarts(sec->name, ".rodata")) - return true; - - /* UBSAN anonymous data */ - if (strstarts(sec->name, ".data..Lubsan") || /* GCC */ - strstarts(sec->name, ".data..L__unnamed_")) /* Clang */ - return true; - - return false; -} - -static bool is_reloc_allowed(struct reloc *reloc) -{ - return section_reference_needed(reloc->sym->sec) =3D=3D is_sec_sym(reloc-= >sym); -} - static struct export *find_export(struct symbol *sym) { struct export *export; @@ -979,11 +946,15 @@ static bool klp_reloc_needed(struct reloc *patched_re= loc) return true; } =20 +/* Return -1 error, 0 success, 1 skip */ static int convert_reloc_sym_to_secsym(struct elf *elf, struct reloc *relo= c) { struct symbol *sym =3D reloc->sym; struct section *sec =3D sym->sec; =20 + if (is_sec_sym(sym)) + return 0; + if (!sec->sym && !elf_create_section_symbol(elf, sec)) return -1; =20 @@ -993,11 +964,15 @@ static int convert_reloc_sym_to_secsym(struct elf *el= f, struct reloc *reloc) return 0; } =20 +/* Return -1 error, 0 success, 1 skip */ static int convert_reloc_secsym_to_sym(struct elf *elf, struct reloc *relo= c) { struct symbol *sym =3D reloc->sym; struct section *sec =3D sym->sec; =20 + if (!is_sec_sym(sym)) + return 0; + /* If the symbol has a dedicated section, it's easy to find */ sym =3D find_symbol_by_offset(sec, 0); if (sym && sym->len =3D=3D sec_size(sec)) @@ -1028,21 +1003,33 @@ found_sym: } =20 /* + * Sections with anonymous or uncorrelated data (strings, UBSAN data) + * need section symbol references. + */ +static bool is_uncorrelated_section(struct section *sec) +{ + return is_string_sec(sec) || + strstarts(sec->name, ".rodata") || + strstarts(sec->name, ".data..Lubsan") || /* GCC */ + strstarts(sec->name, ".data..L__unnamed_"); /* Clang */ +} + +/* * Convert a relocation symbol reference to the needed format: either a se= ction - * symbol or the underlying symbol itself. + * symbol or the underlying symbol itself. Return -1 error, 0 success, 1 = skip. */ static int convert_reloc_sym(struct elf *elf, struct reloc *reloc) { + struct section *sec =3D reloc->sym->sec; + if (reloc_type(reloc) =3D=3D R_NONE) return 1; =20 - if (is_reloc_allowed(reloc)) - return 0; - - if (section_reference_needed(reloc->sym->sec)) + if (is_uncorrelated_section(sec)) return convert_reloc_sym_to_secsym(elf, reloc); - else - return convert_reloc_secsym_to_sym(elf, reloc); + + /* Everything else: references should use named symbols. */ + return convert_reloc_secsym_to_sym(elf, reloc); } =20 /* @@ -1187,13 +1174,6 @@ static int clone_reloc(struct elfs *e, struct reloc = *patched_reloc, struct symbol *out_sym; bool klp; =20 - if (!is_reloc_allowed(patched_reloc)) { - ERROR_FUNC(patched_reloc->sec->base, reloc_offset(patched_reloc), - "missing symbol for reference to %s+%ld", - patched_sym->name, addend); - return -1; - } - klp =3D klp_reloc_needed(patched_reloc); =20 dbg_clone_reloc(sec, offset, patched_sym, addend, export, klp); @@ -1223,7 +1203,7 @@ static int clone_reloc(struct elfs *e, struct reloc *= patched_reloc, =20 /* * For strings, all references use section symbols, thanks to - * section_reference_needed(). clone_symbol() has cloned an empty + * convert_reloc_sym(). clone_symbol() has cloned an empty * version of the string section. Now copy the string itself. */ if (is_string_sec(patched_sym->sec)) {