From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 D3F55224882; Thu, 4 Sep 2025 03:46:56 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1756957617; cv=none; b=aB97CmlZCOvO/WlvSfwngcRJ0BMmQmGN2g8r61Oi+QuEW3fsRz/SrmCwuk6EAsTXWT68kon11PXgADZXaA6rKd80JhzY+hdiy/trQWvIZrqVXT5feGdmX7yyQ3DZd/F8rvlIQQtQhVvTBsxbg7tW3MZHEv9ap5HrwPMvs2By+JM= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1756957617; c=relaxed/simple; bh=huQ/rMnniDWDIFjoLCvgz1AJbkQU2KKmTas/L98LjC4=; h=From:To:Cc:Subject:Date:Message-Id:MIME-Version:Content-Type; b=VwLLujC+/5RhWSrruyOe+vLIXxqv4+sG9Qq1awQeLwAKNZiWHZgR3Hukjre0k+dQdIL7eGAdbAe8/dqLAVLRuZmoRuRHP2/SMdUlB61MWoZV7c12lvDuijXaFq044zkrySRJdKnxebZclW2i+WX8ZiaeO2a1OJV6cNE++Ri8ZKg= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=YbeKPCuH; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="YbeKPCuH" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 5FF6AC4CEF0; Thu, 4 Sep 2025 03:46:56 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1756957616; bh=huQ/rMnniDWDIFjoLCvgz1AJbkQU2KKmTas/L98LjC4=; h=From:To:Cc:Subject:Date:From; b=YbeKPCuH5Ku1My2/NILiDdlcd2lhEDDgpxPq4p42dihRGT7uqezRNNLqJ/6itihKY ZybcsCamMh2A4/2XW+klE6t0epSCXOyfFe3jrAH/62T0mUZnotmWCS1MlyvlvFURjS wBtqSVaPJXeNoAgSY8kOEzIGTq28Prg04cWEP1i4YB5etAXMKujx4zletrhJLce0Ju Tlqsqk2dy2g4br+paCb9iqydk75fbLBcdjQXY5kVfGFCPKF5R6FkTaothOimSf7pe/ o1M21WhmArHLbNBHgSr0GYo9KuyY2qrA//aGDRAEE2i+WimSW2UqqryywqCqDlinNA fkLhdxXvfbK3w== From: Kees Cook To: Peter Zijlstra Cc: Kees Cook , Nathan Chancellor , Vegard Nossum , Miguel Ojeda , Linus Walleij , Jeff Johnson , Randy Dunlap , David Woodhouse , "Russell King (Oracle)" , Nick Desaulniers , Bill Wendling , Justin Stitt , Marco Elver , Przemek Kitszel , Ramon de C Valle , Jonathan Corbet , "Paul E. McKenney" , Nicolas Schier , Masahiro Yamada , Arnd Bergmann , Krzysztof Kozlowski , Sami Tolvanen , Mark Rutland , linux-kernel@vger.kernel.org, llvm@lists.linux.dev, linux-doc@vger.kernel.org, linux-kbuild@vger.kernel.org, linux-arm-kernel@lists.infradead.org, x86@kernel.org, linux-hardening@vger.kernel.org Subject: [PATCH v2 0/9] kcfi: Prepare for GCC support Date: Wed, 3 Sep 2025 20:46:39 -0700 Message-Id: <20250904033217.it.414-kees@kernel.org> X-Mailer: git-send-email 2.34.1 Precedence: bulk X-Mailing-List: linux-kbuild@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 X-Developer-Signature: v=1; a=openpgp-sha256; l=6367; i=kees@kernel.org; h=from:subject:message-id; bh=huQ/rMnniDWDIFjoLCvgz1AJbkQU2KKmTas/L98LjC4=; b=owGbwMvMwCVmps19z/KJym7G02pJDBk7OfNXqRXMPuu3KW/iNZutC1WFrp2pb562kb3h3dTZd 1RePqr401HKwiDGxSArpsgSZOce5+Lxtj3cfa4izBxWJpAhDFycAjARDW2G/3k7WW1vxMecMLya ZlWv0fs7zCJxQkrMl03arwWmGC/dx8rI0G3jZOYpOOvZq+8X2jhnZe4SNDbe8jnVLXeN8/8rO7O SmAA= X-Developer-Key: i=kees@kernel.org; a=openpgp; fpr=A5C3F68F229DD60F723E6E138972F4DFDC6DC026 Content-Transfer-Encoding: 8bit v2: - integrate "transitional" Kconfig patch[2] (nathan, randy, miguel) - add arm32 KCFI trap handler - split pr_info changes (nathan) - clean up my broken SoB (peter) - remove Clang from CONFIG_CFI help (jeff) - add r-b (linus) v1: https://lore.kernel.org/all/20250825141316.work.967-kees@kernel.org/ Hi, With KCFI support in GCC coming[1], we need to make some (relatively small) changes in the kernel to deal with it: - move __nocfi out of compilers-clang.h (so GCC can see it too) - add cfi=debug so future Kees can find fineibt breakage easier - remove problematic __noinitretpoline usage - rename CONFIG_CFI_CLANG to CONFIG_CFI (otherwise it is quite confusing) If I can get some Acks, I will carry this in the hardening tree, unless someone else would like to take it (perhaps tip). Thanks! -Kees [1] https://lore.kernel.org/linux-hardening/20250821064202.work.893-kees@kernel.org/ [2] https://lore.kernel.org/all/20250901182334.make.517-kees@kernel.org/ Kees Cook (9): compiler_types.h: Move __nocfi out of compiler-specific header x86/traps: Clarify KCFI instruction layout x86/cfi: Document the "cfi=" bootparam options x86/cfi: Standardize on common "CFI:" prefix for CFI reports x86/cfi: Add "debug" option to "cfi=" bootparam x86/cfi: Remove __noinitretpoline and __noretpoline kconfig: Add transitional symbol attribute for migration support kcfi: Rename CONFIG_CFI_CLANG to CONFIG_CFI ARM: traps: Implement KCFI trap handler for ARM32 arch/Kconfig | 36 ++++--- arch/arm/Kconfig | 2 +- arch/arm64/Kconfig | 4 +- arch/riscv/Kconfig | 6 +- arch/x86/Kconfig | 12 +-- init/Kconfig | 4 +- kernel/module/Kconfig | 2 +- .../kconfig/tests/err_transitional/Kconfig | 52 +++++++++ scripts/kconfig/tests/transitional/Kconfig | 100 +++++++++++++++++ lib/Kconfig.debug | 2 +- Makefile | 2 +- arch/arm/mm/Makefile | 2 +- arch/riscv/kernel/Makefile | 2 +- arch/riscv/purgatory/Makefile | 2 +- arch/x86/kernel/Makefile | 2 +- arch/x86/purgatory/Makefile | 2 +- kernel/Makefile | 2 +- scripts/kconfig/expr.h | 1 + scripts/kconfig/lexer.l | 1 + scripts/kconfig/parser.y | 47 ++++++++ scripts/kconfig/symbol.c | 16 ++- .../tests/err_transitional/__init__.py | 14 +++ .../tests/err_transitional/expected_stderr | 7 ++ .../kconfig/tests/transitional/__init__.py | 18 ++++ .../tests/transitional/expected_config | 12 +++ .../kconfig/tests/transitional/initial_config | 16 +++ .../admin-guide/kernel-parameters.txt | 18 ++++ Documentation/kbuild/kconfig-language.rst | 32 ++++++ arch/riscv/include/asm/cfi.h | 4 +- arch/x86/include/asm/cfi.h | 4 +- include/asm-generic/vmlinux.lds.h | 2 +- include/linux/cfi.h | 6 +- include/linux/cfi_types.h | 8 +- include/linux/compiler-clang.h | 5 - include/linux/compiler-gcc.h | 4 - include/linux/compiler.h | 2 +- include/linux/compiler_types.h | 4 +- include/linux/init.h | 8 -- tools/include/linux/cfi_types.h | 6 +- tools/perf/util/include/linux/linkage.h | 2 +- arch/arm/mm/cache-fa.S | 2 +- arch/arm/mm/cache-v4.S | 2 +- arch/arm/mm/cache-v4wb.S | 4 +- arch/arm/mm/cache-v4wt.S | 2 +- arch/arm/mm/cache-v6.S | 2 +- arch/arm/mm/cache-v7.S | 2 +- arch/arm/mm/cache-v7m.S | 2 +- arch/arm/mm/proc-arm1020.S | 2 +- arch/arm/mm/proc-arm1020e.S | 2 +- arch/arm/mm/proc-arm1022.S | 2 +- arch/arm/mm/proc-arm1026.S | 2 +- arch/arm/mm/proc-arm920.S | 2 +- arch/arm/mm/proc-arm922.S | 2 +- arch/arm/mm/proc-arm925.S | 2 +- arch/arm/mm/proc-arm926.S | 2 +- arch/arm/mm/proc-arm940.S | 2 +- arch/arm/mm/proc-arm946.S | 2 +- arch/arm/mm/proc-feroceon.S | 2 +- arch/arm/mm/proc-mohawk.S | 2 +- arch/arm/mm/proc-xsc3.S | 2 +- arch/arm/mm/tlb-v4.S | 2 +- arch/arm/kernel/hw_breakpoint.c | 2 +- arch/arm/kernel/traps.c | 102 ++++++++++++++++++ arch/arm64/kernel/debug-monitors.c | 2 +- arch/arm64/kernel/traps.c | 4 +- arch/arm64/kvm/handle_exit.c | 2 +- arch/arm64/net/bpf_jit_comp.c | 2 +- arch/riscv/net/bpf_jit_comp64.c | 4 +- arch/x86/kernel/alternative.c | 44 ++++++-- arch/x86/kernel/cfi.c | 2 +- arch/x86/kernel/kprobes/core.c | 2 +- drivers/misc/lkdtm/cfi.c | 2 +- kernel/module/tree_lookup.c | 2 +- kernel/configs/hardening.config | 2 +- 74 files changed, 569 insertions(+), 118 deletions(-) create mode 100644 scripts/kconfig/tests/err_transitional/Kconfig create mode 100644 scripts/kconfig/tests/transitional/Kconfig create mode 100644 scripts/kconfig/tests/err_transitional/__init__.py create mode 100644 scripts/kconfig/tests/err_transitional/expected_stderr create mode 100644 scripts/kconfig/tests/transitional/__init__.py create mode 100644 scripts/kconfig/tests/transitional/expected_config create mode 100644 scripts/kconfig/tests/transitional/initial_config -- 2.34.1