From b9f174c811e3ae4ae8959dc57e6adb9990e913f4 Mon Sep 17 00:00:00 2001 From: Omar Sandoval Date: Tue, 13 Jun 2023 14:14:56 -0700 Subject: x86/unwind/orc: Add ELF section with ORC version identifier Commits ffb1b4a41016 ("x86/unwind/orc: Add 'signal' field to ORC metadata") and fb799447ae29 ("x86,objtool: Split UNWIND_HINT_EMPTY in two") changed the ORC format. Although ORC is internal to the kernel, it's the only way for external tools to get reliable kernel stack traces on x86-64. In particular, the drgn debugger [1] uses ORC for stack unwinding, and these format changes broke it [2]. As the drgn maintainer, I don't care how often or how much the kernel changes the ORC format as long as I have a way to detect the change. It suffices to store a version identifier in the vmlinux and kernel module ELF files (to use when parsing ORC sections from ELF), and in kernel memory (to use when parsing ORC from a core dump+symbol table). Rather than hard-coding a version number that needs to be manually bumped, Peterz suggested hashing the definitions from orc_types.h. If there is a format change that isn't caught by this, the hashing script can be updated. This patch adds an .orc_header allocated ELF section containing the 20-byte hash to vmlinux and kernel modules, along with the corresponding __start_orc_header and __stop_orc_header symbols in vmlinux. 1: https://github.com/osandov/drgn 2: https://github.com/osandov/drgn/issues/303 Fixes: ffb1b4a41016 ("x86/unwind/orc: Add 'signal' field to ORC metadata") Fixes: fb799447ae29 ("x86,objtool: Split UNWIND_HINT_EMPTY in two") Signed-off-by: Omar Sandoval Signed-off-by: Peter Zijlstra (Intel) Acked-by: Josh Poimboeuf Link: https://lkml.kernel.org/r/aef9c8dc43915b886a8c48509a12ec1b006ca1ca.1686690801.git.osandov@osandov.com --- scripts/mod/modpost.c | 5 +++++ scripts/orc_hash.sh | 16 ++++++++++++++++ 2 files changed, 21 insertions(+) create mode 100644 scripts/orc_hash.sh (limited to 'scripts') diff --git a/scripts/mod/modpost.c b/scripts/mod/modpost.c index d4531d09984d..c12150f96b88 100644 --- a/scripts/mod/modpost.c +++ b/scripts/mod/modpost.c @@ -1979,6 +1979,11 @@ static void add_header(struct buffer *b, struct module *mod) buf_printf(b, "#include \n"); buf_printf(b, "#include \n"); buf_printf(b, "\n"); + buf_printf(b, "#ifdef CONFIG_UNWINDER_ORC\n"); + buf_printf(b, "#include \n"); + buf_printf(b, "ORC_HEADER;\n"); + buf_printf(b, "#endif\n"); + buf_printf(b, "\n"); buf_printf(b, "BUILD_SALT;\n"); buf_printf(b, "BUILD_LTO_INFO;\n"); buf_printf(b, "\n"); diff --git a/scripts/orc_hash.sh b/scripts/orc_hash.sh new file mode 100644 index 000000000000..466611aa0053 --- /dev/null +++ b/scripts/orc_hash.sh @@ -0,0 +1,16 @@ +#!/bin/sh +# SPDX-License-Identifier: GPL-2.0-or-later +# Copyright (c) Meta Platforms, Inc. and affiliates. + +set -e + +printf '%s' '#define ORC_HASH ' + +awk ' +/^#define ORC_(REG|TYPE)_/ { print } +/^struct orc_entry {$/ { p=1 } +p { print } +/^}/ { p=0 }' | + sha1sum | + cut -d " " -f 1 | + sed 's/\([0-9a-f]\{2\}\)/0x\1,/g' -- cgit v1.2.3 From 2049a7d0cbc6ac8e370e836ed68597be04a7dc49 Mon Sep 17 00:00:00 2001 From: Prathu Baronia Date: Thu, 8 Jun 2023 21:14:49 +0530 Subject: scripts: fix the gfp flags header path in gfp-translate Since gfp flags have been shifted to gfp_types.h so update the path in the gfp-translate script. Link: https://lkml.kernel.org/r/20230608154450.21758-1-prathubaronia2011@gmail.com Fixes: cb5a065b4ea9c ("headers/deps: mm: Split out of ") Signed-off-by: Prathu Baronia Reviewed-by: David Hildenbrand Cc: Masahiro Yamada Cc: Nathan Chancellor Cc: Nick Desaulniers Cc: Nicolas Schier Cc: Ingo Molnar Cc: Yury Norov Cc: Signed-off-by: Andrew Morton --- scripts/gfp-translate | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) (limited to 'scripts') diff --git a/scripts/gfp-translate b/scripts/gfp-translate index b2ce416d944b..6c9aed17cf56 100755 --- a/scripts/gfp-translate +++ b/scripts/gfp-translate @@ -63,11 +63,11 @@ fi # Extract GFP flags from the kernel source TMPFILE=`mktemp -t gfptranslate-XXXXXX` || exit 1 -grep -q ___GFP $SOURCE/include/linux/gfp.h +grep -q ___GFP $SOURCE/include/linux/gfp_types.h if [ $? -eq 0 ]; then - grep "^#define ___GFP" $SOURCE/include/linux/gfp.h | sed -e 's/u$//' | grep -v GFP_BITS > $TMPFILE + grep "^#define ___GFP" $SOURCE/include/linux/gfp_types.h | sed -e 's/u$//' | grep -v GFP_BITS > $TMPFILE else - grep "^#define __GFP" $SOURCE/include/linux/gfp.h | sed -e 's/(__force gfp_t)//' | sed -e 's/u)/)/' | grep -v GFP_BITS | sed -e 's/)\//) \//' > $TMPFILE + grep "^#define __GFP" $SOURCE/include/linux/gfp_types.h | sed -e 's/(__force gfp_t)//' | sed -e 's/u)/)/' | grep -v GFP_BITS | sed -e 's/)\//) \//' > $TMPFILE fi # Parse the flags -- cgit v1.2.3 From 6a59cb5158bff13b80f116305155fbe4967a5010 Mon Sep 17 00:00:00 2001 From: Florian Fainelli Date: Wed, 7 Jun 2023 15:13:35 -0700 Subject: scripts/gdb: fix SB_* constants parsing --0000000000009a0c9905fd9173ad Content-Transfer-Encoding: 8bit After f15afbd34d8f ("fs: fix undefined behavior in bit shift for SB_NOUSER") the constants were changed from plain integers which LX_VALUE() can parse to constants using the BIT() macro which causes the following: Reading symbols from build/linux-custom/vmlinux...done. Traceback (most recent call last): File "/home/fainelli/work/buildroot/output/arm64/build/linux-custom/vmlinux-gdb.py", line 25, in import linux.constants File "/home/fainelli/work/buildroot/output/arm64/build/linux-custom/scripts/gdb/linux/constants.py", line 5 LX_SB_RDONLY = ((((1UL))) << (0)) Use LX_GDBPARSED() which does not suffer from that issue. f15afbd34d8f ("fs: fix undefined behavior in bit shift for SB_NOUSER") Link: https://lkml.kernel.org/r/20230607221337.2781730-1-florian.fainelli@broadcom.com Signed-off-by: Florian Fainelli Acked-by: Christian Brauner Cc: Hao Ge Cc: Jan Kiszka Cc: Kieran Bingham Cc: Luis Chamberlain Cc: Pankaj Raghav Signed-off-by: Andrew Morton --- scripts/gdb/linux/constants.py.in | 12 ++++++------ 1 file changed, 6 insertions(+), 6 deletions(-) (limited to 'scripts') diff --git a/scripts/gdb/linux/constants.py.in b/scripts/gdb/linux/constants.py.in index 471300ba176c..50a92c4e9984 100644 --- a/scripts/gdb/linux/constants.py.in +++ b/scripts/gdb/linux/constants.py.in @@ -48,12 +48,12 @@ if IS_BUILTIN(CONFIG_COMMON_CLK): LX_GDBPARSED(CLK_GET_RATE_NOCACHE) /* linux/fs.h */ -LX_VALUE(SB_RDONLY) -LX_VALUE(SB_SYNCHRONOUS) -LX_VALUE(SB_MANDLOCK) -LX_VALUE(SB_DIRSYNC) -LX_VALUE(SB_NOATIME) -LX_VALUE(SB_NODIRATIME) +LX_GDBPARSED(SB_RDONLY) +LX_GDBPARSED(SB_SYNCHRONOUS) +LX_GDBPARSED(SB_MANDLOCK) +LX_GDBPARSED(SB_DIRSYNC) +LX_GDBPARSED(SB_NOATIME) +LX_GDBPARSED(SB_NODIRATIME) /* linux/htimer.h */ LX_GDBPARSED(hrtimer_resolution) -- cgit v1.2.3