From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by smtp.subspace.kernel.org (Postfix) with ESMTP id 8A017275B15; Tue, 1 Jul 2025 13:56:34 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=217.140.110.172 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1751378196; cv=none; b=rbbe1W1yp4U1FG980YMDJI4llXN5Mfx+Ay7WfQVF7eK5vewN+oJ2hfidjF8FU0C+fDLHH4j3/ekssClsQzTpvxBWqybtTYdge259i7lfKgoUUWmExkP4L+Q4Pd6TSfb+goyDUgI2EbwgU9Kt3q7uOX8XOM+45BCSpk6b9T8Hvn0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1751378196; c=relaxed/simple; bh=OjzN30GIiPcplOAaeYUjDuVVavt00lwj5wf5fyxHSgE=; h=From:To:Cc:Subject:Date:Message-Id:MIME-Version; b=hCjUhNlpOp+5G4Rpsg+7XNo5V/3hT+jckl75ilm5IAE0bnRT5YWFbJ3aDM/DZbtgoz9PX6H7l9qLde/feC2Vn+Gs0eWh9yxVvbIhA8qj2e4sRPzMg3vqqxkJH7Zxucpd29VXOA3QRgZEkKtDG3QyhM/wwtudzCIfr7u80kcaHIw= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com; spf=pass smtp.mailfrom=arm.com; arc=none smtp.client-ip=217.140.110.172 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=arm.com Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 4E7141713; Tue, 1 Jul 2025 06:56:18 -0700 (PDT) Received: from e133380.cambridge.arm.com (e133380.arm.com [10.1.197.52]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id CE12C3F58B; Tue, 1 Jul 2025 06:56:23 -0700 (PDT) From: Dave Martin To: linux-kernel@vger.kernel.org Cc: "David S. Miller" , "H. Peter Anvin" , "James E.J. Bottomley" , Akihiko Odaki , Albert Ou , Alexander Gordeev , Alexandre Ghiti , Andreas Larsson , Anton Ivanov , Borislav Petkov , Brian Cain , Catalin Marinas , Chris Zankel , Christian Borntraeger , Christophe Leroy , Dave Hansen , Dinh Nguyen , Geert Uytterhoeven , Guo Ren , Heiko Carstens , Helge Deller , Huacai Chen , Ingo Molnar , Johannes Berg , John Paul Adrian Glaubitz , Jonas Bonn , Kees Cook , Madhavan Srinivasan , Max Filippov , Michael Ellerman , Nicholas Piggin , Oleg Nesterov , Palmer Dabbelt , Paul Walmsley , Rich Felker , Richard Weinberger , Russell King , Stafford Horne , Stefan Kristiansson , Sven Schnelle , Thomas Bogendoerfer , Thomas Gleixner , Vasily Gorbik , Vineet Gupta , WANG Xuerui , Will Deacon , Yoshinori Sato , linux-arch@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-csky@vger.kernel.org, linux-hexagon@vger.kernel.org, linux-m68k@lists.linux-m68k.org, linux-mips@vger.kernel.org, linux-openrisc@vger.kernel.org, linux-parisc@vger.kernel.org, linux-riscv@lists.infradead.org, linux-s390@vger.kernel.org, linux-sh@vger.kernel.org, linux-snps-arc@lists.infradead.org, linux-um@lists.infradead.org, linuxppc-dev@lists.ozlabs.org, loongarch@lists.linux.dev, sparclinux@vger.kernel.org, x86@kernel.org Subject: [PATCH 00/23] binfmt_elf,arch/*: Use elf.h for coredump note names Date: Tue, 1 Jul 2025 14:55:53 +0100 Message-Id: <20250701135616.29630-1-Dave.Martin@arm.com> X-Mailer: git-send-email 2.34.1 Precedence: bulk X-Mailing-List: linux-s390@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit This series aims to clean up an aspect of coredump generation: ELF coredumps contain a set of notes describing the state of machine registers and other information about the dumped process. Notes are identified by a numeric identifier n_type and a "name" string, although this terminology is somewhat misleading. Officially, the "name" of a note is really an "originator" or namespace identifier that indicates how to interpret n_type [1], although in practice it is often used more loosely. Either way, each kind of note needs _both_ a specific "name" string and a specific n_type to identify it robustly. To centralise this knowledge in one place and avoid the need for ad-hoc code to guess the correct name for a given note, commit 7da8e4ad4df0 ("elf: Define note name macros") [2] added an explicit NN_ #define in elf.h to give the name corresponding to each named note type NT_. Now that the note name for each note is specified explicitly, the remaining guesswork for determining the note name for common and arch-specific regsets in ELF core dumps can be eliminated. This series aims to do just that: * Patch 2 adds a user_regset field to specify the note name, and a helper macro to populate it correctly alongside the note type. * Patch 3 ports away the ad-hoc note names in the common coredump code. * Patches 4-22 make the arch-specific changes. (This is pretty mechanical for most arches.) * The final patch adds a WARN() when no note name is specified, and simplifies the fallback guess. This should only be applied when all arches have ported across. See the individual patches for details. Testing: * x86, arm64: Booted in a VM and triggered a core dump with no WARN(), and verified that the dumped notes are the same. * arm: Build-tested only (for now). * Other arches: not tested yet Any help with testing is appreciated. If the following generates the same notes (as dumped by readelf -n core) and doesn't trigger a WARN, then we are probably good. $ sleep 60 & $ kill -QUIT $! (Register content might differ between runs, but it should be safe to ignore that -- this series only deals with the note names and types.) Cheers ---Dave [1] System V Application Binary Interface, Edition 4.1, Section 5 (Program Loading and Dynamic Linking) -> "Note Section" https://refspecs.linuxfoundation.org/elf/gabi41.pdf [2] elf: Define note name macros https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/include/uapi/linux/elf.h?id=7da8e4ad4df0dd12f37357af62ce1b63e75ae2e6 Dave Martin (23): regset: Fix kerneldoc for struct regset_get() in user_regset regset: Add explicit core note name in struct user_regset binfmt_elf: Dump non-arch notes with strictly matching name and type ARC: ptrace: Use USER_REGSET_NOTE_TYPE() to specify regset note names ARM: ptrace: Use USER_REGSET_NOTE_TYPE() to specify regset note names arm64: ptrace: Use USER_REGSET_NOTE_TYPE() to specify regset note names csky: ptrace: Use USER_REGSET_NOTE_TYPE() to specify regset note names hexagon: ptrace: Use USER_REGSET_NOTE_TYPE() to specify regset note names LoongArch: ptrace: Use USER_REGSET_NOTE_TYPE() to specify regset note names m68k: ptrace: Use USER_REGSET_NOTE_TYPE() to specify regset note names MIPS: ptrace: Use USER_REGSET_NOTE_TYPE() to specify regset note names nios2: ptrace: Use USER_REGSET_NOTE_TYPE() to specify regset note names openrisc: ptrace: Use USER_REGSET_NOTE_TYPE() to specify regset note names parisc: ptrace: Use USER_REGSET_NOTE_TYPE() to specify regset note names powerpc/ptrace: Use USER_REGSET_NOTE_TYPE() to specify regset note names riscv: ptrace: Use USER_REGSET_NOTE_TYPE() to specify regset note names s390/ptrace: Use USER_REGSET_NOTE_TYPE() to specify regset note names sh: ptrace: Use USER_REGSET_NOTE_TYPE() to specify regset note names sparc: ptrace: Use USER_REGSET_NOTE_TYPE() to specify regset note names x86/ptrace: Use USER_REGSET_NOTE_TYPE() to specify regset note names um: ptrace: Use USER_REGSET_NOTE_TYPE() to specify regset note names xtensa: ptrace: Use USER_REGSET_NOTE_TYPE() to specify regset note names binfmt_elf: Warn on missing or suspicious regset note names arch/arc/kernel/ptrace.c | 4 +- arch/arm/kernel/ptrace.c | 6 +- arch/arm64/kernel/ptrace.c | 52 ++++++++--------- arch/csky/kernel/ptrace.c | 4 +- arch/hexagon/kernel/ptrace.c | 2 +- arch/loongarch/kernel/ptrace.c | 16 ++--- arch/m68k/kernel/ptrace.c | 4 +- arch/mips/kernel/ptrace.c | 20 +++---- arch/nios2/kernel/ptrace.c | 2 +- arch/openrisc/kernel/ptrace.c | 4 +- arch/parisc/kernel/ptrace.c | 8 +-- arch/powerpc/kernel/ptrace/ptrace-view.c | 74 ++++++++++++------------ arch/riscv/kernel/ptrace.c | 12 ++-- arch/s390/kernel/ptrace.c | 42 +++++++------- arch/sh/kernel/ptrace_32.c | 4 +- arch/sparc/kernel/ptrace_32.c | 4 +- arch/sparc/kernel/ptrace_64.c | 8 +-- arch/x86/kernel/ptrace.c | 22 +++---- arch/x86/um/ptrace.c | 10 ++-- arch/xtensa/kernel/ptrace.c | 4 +- fs/binfmt_elf.c | 36 +++++++----- fs/binfmt_elf_fdpic.c | 17 +++--- include/linux/regset.h | 12 +++- 23 files changed, 194 insertions(+), 173 deletions(-) base-commit: 86731a2a651e58953fc949573895f2fa6d456841 -- 2.34.1