From nobody Tue Dec 2 00:25:38 2025 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 B49BE2FB62E; Mon, 24 Nov 2025 10:44:05 +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=1763981048; cv=none; b=C1EMQfinohxbYcUbhkubzB+U9izABod5hwkwLMMSToGyyx47/mM41fNkZZgSl7eDDM9DSLo7JIPLSRQLwpk8PuLFj+vDobQ171Pk3gFcoSoANP/d3BzCa9P0SoIrDzZkeJ/jvG4E3MlyG16t47W4kunsrUOlYWbvdeCpedEwMXc= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1763981048; c=relaxed/simple; bh=3n0ekYqwkUslMIT7bhslnj/63LR86fMc231pBmGXZ/U=; h=Date:From:To:Subject:Cc:In-Reply-To:References:MIME-Version: Message-ID:Content-Type; b=pFAMPbaRMQz4PEHemXPf0BgLd0VpRB8PhyfvUBisN2o6vSjlvthMazLZLBhMeo5Wxxc65cgM68GnuAMc8wRqMVGGfIih1AtaLFdGwljGHQE+gToGfZYA7zgQlEefA9rqp7Xir6F7fE4dHvgImPW4+bXnMOoCOVfraE1PohnIB0g= 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=R7cXKE/g; dkim=permerror (0-bit key) header.d=linutronix.de header.i=@linutronix.de header.b=UfSeXq14; 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="R7cXKE/g"; dkim=permerror (0-bit key) header.d=linutronix.de header.i=@linutronix.de header.b="UfSeXq14" Date: Mon, 24 Nov 2025 10:44:01 -0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1763981042; 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: in-reply-to:in-reply-to:references:references; bh=PfX3flpUk4b/ejynbfhrYREm1lxj8oJZeekWdIFbdXk=; b=R7cXKE/gZhzWHgrS3kIIK3Rb/H8uRONF7l0nR02Fqeju4YPQ/tO9X2e1jk1v03BOfCXZQw OhtOY6PvVfUoDihdLZYLS69MZ44b5gXVYWga4fjXJRldDnHg+DaH7gQyE4qD61yb/eMh3O O9IQlqjQIordY8bvC0R/CRAvCkIJ9RoHA2aUPHEOVJimf9uLNJIZEHdOh8GqNxzgoEbAM1 +6OzIdcBr8BPkOR/1gqwLIM0NT3rXtWj2aEcu7lzhHiL61N/YTW6SEWsMemzbqnZmcF+1t 6ikvbYUDSXQpLCd7oBT7U/fzywvSr/nt1Vwxrl768Y3X8LK3JokgVy8JcvkU3Q== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1763981042; 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: in-reply-to:in-reply-to:references:references; bh=PfX3flpUk4b/ejynbfhrYREm1lxj8oJZeekWdIFbdXk=; b=UfSeXq142tg872WBkVa64NBzKFfkdIR+uopLSy01P4w4qJp7Geb58sYkBvtACFOIsKuDpc C4nVZt/+FSIKPiDQ== From: "tip-bot2 for Alexandre Chartre" Sender: tip-bot2@linutronix.de Reply-to: linux-kernel@vger.kernel.org To: linux-tip-commits@vger.kernel.org Subject: [tip: objtool/core] objtool: Function to get the name of a CPU feature Cc: Alexandre Chartre , "Peter Zijlstra (Intel)" , Josh Poimboeuf , x86@kernel.org, linux-kernel@vger.kernel.org In-Reply-To: <20251121095340.464045-27-alexandre.chartre@oracle.com> References: <20251121095340.464045-27-alexandre.chartre@oracle.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Message-ID: <176398104154.498.14035591969424868341.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: afff4e5820e9a0d609740a83c366f3f0335db342 Gitweb: https://git.kernel.org/tip/afff4e5820e9a0d609740a83c366f3f03= 35db342 Author: Alexandre Chartre AuthorDate: Fri, 21 Nov 2025 10:53:36 +01:00 Committer: Peter Zijlstra CommitterDate: Mon, 24 Nov 2025 11:35:06 +01:00 objtool: Function to get the name of a CPU feature Add a function to get the name of a CPU feature. The function is architecture dependent and currently only implemented for x86. The feature names are automatically generated from the cpufeatures.h include file. Signed-off-by: Alexandre Chartre Signed-off-by: Peter Zijlstra (Intel) Acked-by: Josh Poimboeuf Link: https://patch.msgid.link/20251121095340.464045-27-alexandre.chartre@o= racle.com Reported-by: Borislav Petkov (AMD) Tested-by: Borislav Petkov (AMD) --- tools/arch/x86/tools/gen-cpu-feature-names-x86.awk | 33 +++++++++++++- tools/objtool/.gitignore | 1 +- tools/objtool/Makefile | 1 +- tools/objtool/arch/loongarch/special.c | 5 ++- tools/objtool/arch/powerpc/special.c | 5 ++- tools/objtool/arch/x86/Build | 13 ++++- tools/objtool/arch/x86/special.c | 10 ++++- tools/objtool/include/objtool/special.h | 2 +- 8 files changed, 69 insertions(+), 1 deletion(-) create mode 100644 tools/arch/x86/tools/gen-cpu-feature-names-x86.awk diff --git a/tools/arch/x86/tools/gen-cpu-feature-names-x86.awk b/tools/arc= h/x86/tools/gen-cpu-feature-names-x86.awk new file mode 100644 index 0000000..1b1c1d8 --- /dev/null +++ b/tools/arch/x86/tools/gen-cpu-feature-names-x86.awk @@ -0,0 +1,33 @@ +#!/bin/awk -f +# SPDX-License-Identifier: GPL-2.0 +# +# Copyright (c) 2025, Oracle and/or its affiliates. +# +# Usage: awk -f gen-cpu-feature-names-x86.awk cpufeatures.h > cpu-feature-= names.c +# + +BEGIN { + print "/* cpu feature name array generated from cpufeatures.h */" + print "/* Do not change this code. */" + print + print "static const char *cpu_feature_names[(NCAPINTS+NBUGINTS)*32] =3D {" + + feature_expr =3D "(X86_FEATURE_[A-Z0-9_]+)\\s+\\(([0-9*+ ]+)\\)" + debug_expr =3D "(X86_BUG_[A-Z0-9_]+)\\s+X86_BUG\\(([0-9*+ ]+)\\)" +} + +/^#define X86_FEATURE_/ { + if (match($0, feature_expr, m)) { + print "\t[" m[2] "] =3D \"" m[1] "\"," + } +} + +/^#define X86_BUG_/ { + if (match($0, debug_expr, m)) { + print "\t[NCAPINTS*32+(" m[2] ")] =3D \"" m[1] "\"," + } +} + +END { + print "};" +} diff --git a/tools/objtool/.gitignore b/tools/objtool/.gitignore index 7593036..73d8831 100644 --- a/tools/objtool/.gitignore +++ b/tools/objtool/.gitignore @@ -1,4 +1,5 @@ # SPDX-License-Identifier: GPL-2.0-only +arch/x86/lib/cpu-feature-names.c arch/x86/lib/inat-tables.c /objtool feature diff --git a/tools/objtool/Makefile b/tools/objtool/Makefile index df793ca..66397d7 100644 --- a/tools/objtool/Makefile +++ b/tools/objtool/Makefile @@ -125,6 +125,7 @@ $(LIBSUBCMD)-clean: clean: $(LIBSUBCMD)-clean $(call QUIET_CLEAN, objtool) $(RM) $(OBJTOOL) $(Q)find $(OUTPUT) -name '*.o' -delete -o -name '\.*.cmd' -delete -o -nam= e '\.*.d' -delete + $(Q)$(RM) $(OUTPUT)arch/x86/lib/cpu-feature-names.c $(OUTPUT)fixdep $(Q)$(RM) $(OUTPUT)arch/x86/lib/inat-tables.c $(OUTPUT)fixdep $(Q)$(RM) -- $(OUTPUT)FEATURE-DUMP.objtool $(Q)$(RM) -r -- $(OUTPUT)feature diff --git a/tools/objtool/arch/loongarch/special.c b/tools/objtool/arch/lo= ongarch/special.c index a80b75f..aba7741 100644 --- a/tools/objtool/arch/loongarch/special.c +++ b/tools/objtool/arch/loongarch/special.c @@ -194,3 +194,8 @@ struct reloc *arch_find_switch_table(struct objtool_fil= e *file, =20 return rodata_reloc; } + +const char *arch_cpu_feature_name(int feature_number) +{ + return NULL; +} diff --git a/tools/objtool/arch/powerpc/special.c b/tools/objtool/arch/powe= rpc/special.c index 5161068..8f9bf61 100644 --- a/tools/objtool/arch/powerpc/special.c +++ b/tools/objtool/arch/powerpc/special.c @@ -18,3 +18,8 @@ struct reloc *arch_find_switch_table(struct objtool_file = *file, { exit(-1); } + +const char *arch_cpu_feature_name(int feature_number) +{ + return NULL; +} diff --git a/tools/objtool/arch/x86/Build b/tools/objtool/arch/x86/Build index 3dedb2f..febee0b 100644 --- a/tools/objtool/arch/x86/Build +++ b/tools/objtool/arch/x86/Build @@ -1,5 +1,5 @@ -objtool-y +=3D special.o objtool-y +=3D decode.o +objtool-y +=3D special.o objtool-y +=3D orc.o =20 inat_tables_script =3D ../arch/x86/tools/gen-insn-attr-x86.awk @@ -12,3 +12,14 @@ $(OUTPUT)arch/x86/lib/inat-tables.c: $(inat_tables_scrip= t) $(inat_tables_maps) $(OUTPUT)arch/x86/decode.o: $(OUTPUT)arch/x86/lib/inat-tables.c =20 CFLAGS_decode.o +=3D -I$(OUTPUT)arch/x86/lib + +cpu_features =3D ../arch/x86/include/asm/cpufeatures.h +cpu_features_script =3D ../arch/x86/tools/gen-cpu-feature-names-x86.awk + +$(OUTPUT)arch/x86/lib/cpu-feature-names.c: $(cpu_features_script) $(cpu_fe= atures) + $(call rule_mkdir) + $(Q)$(call echo-cmd,gen)$(AWK) -f $(cpu_features_script) $(cpu_features) = > $@ + +$(OUTPUT)arch/x86/special.o: $(OUTPUT)arch/x86/lib/cpu-feature-names.c + +CFLAGS_special.o +=3D -I$(OUTPUT)arch/x86/lib diff --git a/tools/objtool/arch/x86/special.c b/tools/objtool/arch/x86/spec= ial.c index 0930076..e817a3f 100644 --- a/tools/objtool/arch/x86/special.c +++ b/tools/objtool/arch/x86/special.c @@ -4,6 +4,10 @@ #include #include #include +#include + +/* cpu feature name array generated from cpufeatures.h */ +#include "cpu-feature-names.c" =20 void arch_handle_alternative(struct special_alt *alt) { @@ -134,3 +138,9 @@ struct reloc *arch_find_switch_table(struct objtool_fil= e *file, *table_size =3D 0; return rodata_reloc; } + +const char *arch_cpu_feature_name(int feature_number) +{ + return (feature_number < ARRAY_SIZE(cpu_feature_names)) ? + cpu_feature_names[feature_number] : NULL; +} diff --git a/tools/objtool/include/objtool/special.h b/tools/objtool/includ= e/objtool/special.h index b224107..121c376 100644 --- a/tools/objtool/include/objtool/special.h +++ b/tools/objtool/include/objtool/special.h @@ -38,4 +38,6 @@ bool arch_support_alt_relocation(struct special_alt *spec= ial_alt, struct reloc *arch_find_switch_table(struct objtool_file *file, struct instruction *insn, unsigned long *table_size); +const char *arch_cpu_feature_name(int feature_number); + #endif /* _SPECIAL_H */