From 53f7109ef957315ab53205ba3a3f4f48874c0428 Mon Sep 17 00:00:00 2001 From: Peter Zijlstra Date: Tue, 8 Mar 2022 16:30:45 +0100 Subject: objtool: Rename --duplicate to --lto In order to prepare for LTO like objtool runs for modules, rename the duplicate argument to lto. Signed-off-by: Peter Zijlstra (Intel) Acked-by: Josh Poimboeuf Link: https://lore.kernel.org/r/20220308154319.172584233@infradead.org --- scripts/link-vmlinux.sh | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'scripts/link-vmlinux.sh') diff --git a/scripts/link-vmlinux.sh b/scripts/link-vmlinux.sh index 666f7bbc13eb..9b08dca26f99 100755 --- a/scripts/link-vmlinux.sh +++ b/scripts/link-vmlinux.sh @@ -115,7 +115,7 @@ objtool_link() objtoolcmd="orc generate" fi - objtoolopt="${objtoolopt} --duplicate" + objtoolopt="${objtoolopt} --lto" if is_enabled CONFIG_FTRACE_MCOUNT_USE_OBJTOOL; then objtoolopt="${objtoolopt} --mcount" -- cgit From ed53a0d971926e484d86cce617ec02a7ee85c3fe Mon Sep 17 00:00:00 2001 From: Peter Zijlstra Date: Tue, 8 Mar 2022 16:30:56 +0100 Subject: x86/alternative: Use .ibt_endbr_seal to seal indirect calls Objtool's --ibt option generates .ibt_endbr_seal which lists superfluous ENDBR instructions. That is those instructions for which the function is never indirectly called. Overwrite these ENDBR instructions with a NOP4 such that these function can never be indirect called, reducing the number of viable ENDBR targets in the kernel. Signed-off-by: Peter Zijlstra (Intel) Acked-by: Josh Poimboeuf Link: https://lore.kernel.org/r/20220308154319.822545231@infradead.org --- scripts/link-vmlinux.sh | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-) (limited to 'scripts/link-vmlinux.sh') diff --git a/scripts/link-vmlinux.sh b/scripts/link-vmlinux.sh index 9b08dca26f99..f704034ebbe6 100755 --- a/scripts/link-vmlinux.sh +++ b/scripts/link-vmlinux.sh @@ -108,7 +108,9 @@ objtool_link() local objtoolcmd; local objtoolopt; - if is_enabled CONFIG_LTO_CLANG && is_enabled CONFIG_STACK_VALIDATION; then + if is_enabled CONFIG_STACK_VALIDATION && \ + ( is_enabled CONFIG_LTO_CLANG || is_enabled CONFIG_X86_KERNEL_IBT ); then + # Don't perform vmlinux validation unless explicitly requested, # but run objtool on vmlinux.o now that we have an object file. if is_enabled CONFIG_UNWINDER_ORC; then @@ -117,6 +119,10 @@ objtool_link() objtoolopt="${objtoolopt} --lto" + if is_enabled CONFIG_X86_KERNEL_IBT; then + objtoolopt="${objtoolopt} --ibt" + fi + if is_enabled CONFIG_FTRACE_MCOUNT_USE_OBJTOOL; then objtoolopt="${objtoolopt} --mcount" fi @@ -168,7 +174,7 @@ vmlinux_link() # skip output file argument shift - if is_enabled CONFIG_LTO_CLANG; then + if is_enabled CONFIG_LTO_CLANG || is_enabled CONFIG_X86_KERNEL_IBT; then # Use vmlinux.o instead of performing the slow LTO link again. objs=vmlinux.o libs= -- cgit From 099c22bdca406733c80f3d34ea2d2554bd15fb16 Mon Sep 17 00:00:00 2001 From: Masahiro Yamada Date: Tue, 29 Mar 2022 11:14:36 +0900 Subject: kbuild: fix empty ${PYTHON} in scripts/link-vmlinux.sh The two commits d8d2d38275c1 ("kbuild: remove PYTHON variable") a8cccdd95473 ("init: lto: ensure initcall ordering") were applied in the same development cycle, into two different trees. After they were merged together, this ${PYTHON} expands to an empty string. Therefore, ${srctree}/scripts/jobserver-exec is executed directly. (it has the executable bit set) This is working but let's fix the code into the intended form. Signed-off-by: Masahiro Yamada Reviewed-by: Nick Desaulniers Reviewed-by: Sedat Dilek --- scripts/link-vmlinux.sh | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'scripts/link-vmlinux.sh') diff --git a/scripts/link-vmlinux.sh b/scripts/link-vmlinux.sh index f704034ebbe6..20f44504a644 100755 --- a/scripts/link-vmlinux.sh +++ b/scripts/link-vmlinux.sh @@ -50,7 +50,7 @@ gen_initcalls() { info GEN .tmp_initcalls.lds - ${PYTHON} ${srctree}/scripts/jobserver-exec \ + ${PYTHON3} ${srctree}/scripts/jobserver-exec \ ${PERL} ${srctree}/scripts/generate_initcall_order.pl \ ${KBUILD_VMLINUX_OBJS} ${KBUILD_VMLINUX_LIBS} \ > .tmp_initcalls.lds -- cgit From dbae0a934f09208075ec3e73491bd0844e1397b3 Mon Sep 17 00:00:00 2001 From: Borislav Petkov Date: Thu, 27 Jan 2022 12:56:23 +0100 Subject: x86/cpu: Remove CONFIG_X86_SMAP and "nosmap" Those were added as part of the SMAP enablement but SMAP is currently an integral part of kernel proper and there's no need to disable it anymore. Rip out that functionality. Leave --uaccess default on for objtool as this is what objtool should do by default anyway. If still needed - clearcpuid=smap. Signed-off-by: Borislav Petkov Reviewed-by: Lai Jiangshan Reviewed-by: Kees Cook Link: https://lore.kernel.org/r/20220127115626.14179-4-bp@alien8.de --- scripts/link-vmlinux.sh | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) (limited to 'scripts/link-vmlinux.sh') diff --git a/scripts/link-vmlinux.sh b/scripts/link-vmlinux.sh index 20f44504a644..3a2fffdf49d4 100755 --- a/scripts/link-vmlinux.sh +++ b/scripts/link-vmlinux.sh @@ -146,9 +146,9 @@ objtool_link() if is_enabled CONFIG_RETPOLINE; then objtoolopt="${objtoolopt} --retpoline" fi - if is_enabled CONFIG_X86_SMAP; then - objtoolopt="${objtoolopt} --uaccess" - fi + + objtoolopt="${objtoolopt} --uaccess" + if is_enabled CONFIG_SLS; then objtoolopt="${objtoolopt} --sls" fi -- cgit From 4a5de9b76fcb3f477f73d5a63f6e27709e8af81f Mon Sep 17 00:00:00 2001 From: Josh Poimboeuf Date: Mon, 18 Apr 2022 09:50:20 -0700 Subject: objtool: Enable unreachable warnings for CLANG LTO With IBT support in, objtool is now fully capable of following vmlinux code flow in LTO mode. Start reporting unreachable warnings for Clang LTO as well. Fixes: ed53a0d97192 ("x86/alternative: Use .ibt_endbr_seal to seal indirect calls") Signed-off-by: Josh Poimboeuf Signed-off-by: Peter Zijlstra (Intel) Link: https://lkml.kernel.org/r/7b12df54bceeb0761fe9fc8269ea0c00501214a9.1650300597.git.jpoimboe@redhat.com --- scripts/link-vmlinux.sh | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'scripts/link-vmlinux.sh') diff --git a/scripts/link-vmlinux.sh b/scripts/link-vmlinux.sh index 20f44504a644..9361a1ef02c9 100755 --- a/scripts/link-vmlinux.sh +++ b/scripts/link-vmlinux.sh @@ -140,7 +140,7 @@ objtool_link() if ! is_enabled CONFIG_FRAME_POINTER; then objtoolopt="${objtoolopt} --no-fp" fi - if is_enabled CONFIG_GCOV_KERNEL || is_enabled CONFIG_LTO_CLANG; then + if is_enabled CONFIG_GCOV_KERNEL; then objtoolopt="${objtoolopt} --no-unreachable" fi if is_enabled CONFIG_RETPOLINE; then -- cgit From 2daf7faba7ded8703e4b4ebc8b161f22272fc91a Mon Sep 17 00:00:00 2001 From: Josh Poimboeuf Date: Mon, 18 Apr 2022 09:50:26 -0700 Subject: objtool: Reorganize cmdline options Split the existing options into two groups: actions, which actually do something; and options, which modify the actions in some way. Also there's no need to have short flags for all the non-action options. Reserve short flags for the more important actions. While at it: - change a few of the short flags to be more intuitive - make option descriptions more consistently descriptive - sort options in the source like they are when printed - move options to a global struct Signed-off-by: Josh Poimboeuf Signed-off-by: Peter Zijlstra (Intel) Reviewed-by: Miroslav Benes Link: https://lkml.kernel.org/r/9dcaa752f83aca24b1b21f0b0eeb28a0c181c0b0.1650300597.git.jpoimboe@redhat.com --- scripts/link-vmlinux.sh | 30 +++++++++++++++++++----------- 1 file changed, 19 insertions(+), 11 deletions(-) (limited to 'scripts/link-vmlinux.sh') diff --git a/scripts/link-vmlinux.sh b/scripts/link-vmlinux.sh index 9361a1ef02c9..c6e9fef61b11 100755 --- a/scripts/link-vmlinux.sh +++ b/scripts/link-vmlinux.sh @@ -117,8 +117,6 @@ objtool_link() objtoolcmd="orc generate" fi - objtoolopt="${objtoolopt} --lto" - if is_enabled CONFIG_X86_KERNEL_IBT; then objtoolopt="${objtoolopt} --ibt" fi @@ -126,6 +124,8 @@ objtool_link() if is_enabled CONFIG_FTRACE_MCOUNT_USE_OBJTOOL; then objtoolopt="${objtoolopt} --mcount" fi + + objtoolopt="${objtoolopt} --lto" fi if is_enabled CONFIG_VMLINUX_VALIDATION; then @@ -133,25 +133,33 @@ objtool_link() fi if [ -n "${objtoolopt}" ]; then + if [ -z "${objtoolcmd}" ]; then objtoolcmd="check" fi - objtoolopt="${objtoolopt} --vmlinux" - if ! is_enabled CONFIG_FRAME_POINTER; then - objtoolopt="${objtoolopt} --no-fp" - fi - if is_enabled CONFIG_GCOV_KERNEL; then - objtoolopt="${objtoolopt} --no-unreachable" - fi + if is_enabled CONFIG_RETPOLINE; then objtoolopt="${objtoolopt} --retpoline" fi + + if is_enabled CONFIG_SLS; then + objtoolopt="${objtoolopt} --sls" + fi + if is_enabled CONFIG_X86_SMAP; then objtoolopt="${objtoolopt} --uaccess" fi - if is_enabled CONFIG_SLS; then - objtoolopt="${objtoolopt} --sls" + + if ! is_enabled CONFIG_FRAME_POINTER; then + objtoolopt="${objtoolopt} --no-fp" fi + + if is_enabled CONFIG_GCOV_KERNEL; then + objtoolopt="${objtoolopt} --no-unreachable" + fi + + objtoolopt="${objtoolopt} --vmlinux" + info OBJTOOL ${1} tools/objtool/objtool ${objtoolcmd} ${objtoolopt} ${1} fi -- cgit From b51277eb9775ce916f9efd2c51533e481180c1e8 Mon Sep 17 00:00:00 2001 From: Josh Poimboeuf Date: Mon, 18 Apr 2022 09:50:27 -0700 Subject: objtool: Ditch subcommands Objtool has a fairly singular focus. It runs on object files and does validations and transformations which can be combined in various ways. The subcommand model has never been a good fit, making it awkward to combine and remove options. Remove the "check" and "orc" subcommands in favor of a more traditional cmdline option model. This makes it much more flexible to use, and easier to port individual features to other arches. Signed-off-by: Josh Poimboeuf Signed-off-by: Peter Zijlstra (Intel) Reviewed-by: Miroslav Benes Link: https://lkml.kernel.org/r/5c61ebf805e90aefc5fa62bc63468ffae53b9df6.1650300597.git.jpoimboe@redhat.com --- scripts/link-vmlinux.sh | 13 +++++-------- 1 file changed, 5 insertions(+), 8 deletions(-) (limited to 'scripts/link-vmlinux.sh') diff --git a/scripts/link-vmlinux.sh b/scripts/link-vmlinux.sh index c6e9fef61b11..f6db79b11573 100755 --- a/scripts/link-vmlinux.sh +++ b/scripts/link-vmlinux.sh @@ -113,9 +113,6 @@ objtool_link() # Don't perform vmlinux validation unless explicitly requested, # but run objtool on vmlinux.o now that we have an object file. - if is_enabled CONFIG_UNWINDER_ORC; then - objtoolcmd="orc generate" - fi if is_enabled CONFIG_X86_KERNEL_IBT; then objtoolopt="${objtoolopt} --ibt" @@ -125,6 +122,10 @@ objtool_link() objtoolopt="${objtoolopt} --mcount" fi + if is_enabled CONFIG_UNWINDER_ORC; then + objtoolopt="${objtoolopt} --orc" + fi + objtoolopt="${objtoolopt} --lto" fi @@ -134,10 +135,6 @@ objtool_link() if [ -n "${objtoolopt}" ]; then - if [ -z "${objtoolcmd}" ]; then - objtoolcmd="check" - fi - if is_enabled CONFIG_RETPOLINE; then objtoolopt="${objtoolopt} --retpoline" fi @@ -161,7 +158,7 @@ objtool_link() objtoolopt="${objtoolopt} --vmlinux" info OBJTOOL ${1} - tools/objtool/objtool ${objtoolcmd} ${objtoolopt} ${1} + tools/objtool/objtool ${objtoolopt} ${1} fi } -- cgit From 7dce62041ac34b613a5ed1bd937117e492e06dc8 Mon Sep 17 00:00:00 2001 From: Josh Poimboeuf Date: Mon, 18 Apr 2022 09:50:33 -0700 Subject: objtool: Make stack validation optional Make stack validation an explicit cmdline option so that individual objtool features can be enabled individually by other arches. Signed-off-by: Josh Poimboeuf Signed-off-by: Peter Zijlstra (Intel) Reviewed-by: Miroslav Benes Link: https://lkml.kernel.org/r/52da143699574d756e65ca4c9d4acaffe9b0fe5f.1650300597.git.jpoimboe@redhat.com --- scripts/link-vmlinux.sh | 4 ++++ 1 file changed, 4 insertions(+) (limited to 'scripts/link-vmlinux.sh') diff --git a/scripts/link-vmlinux.sh b/scripts/link-vmlinux.sh index f6db79b11573..0140bfa32c0c 100755 --- a/scripts/link-vmlinux.sh +++ b/scripts/link-vmlinux.sh @@ -126,6 +126,10 @@ objtool_link() objtoolopt="${objtoolopt} --orc" fi + if is_enabled CONFIG_STACK_VALIDATION; then + objtoolopt="${objtoolopt} --stackval" + fi + objtoolopt="${objtoolopt} --lto" fi -- cgit From 03f16cd020eb8bb2eb837e2090086f296a9fa91d Mon Sep 17 00:00:00 2001 From: Josh Poimboeuf Date: Mon, 18 Apr 2022 09:50:36 -0700 Subject: objtool: Add CONFIG_OBJTOOL Now that stack validation is an optional feature of objtool, add CONFIG_OBJTOOL and replace most usages of CONFIG_STACK_VALIDATION with it. CONFIG_STACK_VALIDATION can now be considered to be frame-pointer specific. CONFIG_UNWINDER_ORC is already inherently valid for live patching, so no need to "validate" it. Signed-off-by: Josh Poimboeuf Signed-off-by: Peter Zijlstra (Intel) Reviewed-by: Miroslav Benes Link: https://lkml.kernel.org/r/939bf3d85604b2a126412bf11af6e3bd3b872bcb.1650300597.git.jpoimboe@redhat.com --- scripts/link-vmlinux.sh | 32 ++++++++++++++++++-------------- 1 file changed, 18 insertions(+), 14 deletions(-) (limited to 'scripts/link-vmlinux.sh') diff --git a/scripts/link-vmlinux.sh b/scripts/link-vmlinux.sh index 0140bfa32c0c..5101a7fbfaaf 100755 --- a/scripts/link-vmlinux.sh +++ b/scripts/link-vmlinux.sh @@ -108,8 +108,11 @@ objtool_link() local objtoolcmd; local objtoolopt; - if is_enabled CONFIG_STACK_VALIDATION && \ - ( is_enabled CONFIG_LTO_CLANG || is_enabled CONFIG_X86_KERNEL_IBT ); then + if ! is_enabled CONFIG_OBJTOOL; then + return; + fi + + if is_enabled CONFIG_LTO_CLANG || is_enabled CONFIG_X86_KERNEL_IBT; then # Don't perform vmlinux validation unless explicitly requested, # but run objtool on vmlinux.o now that we have an object file. @@ -126,10 +129,23 @@ objtool_link() objtoolopt="${objtoolopt} --orc" fi + if is_enabled CONFIG_RETPOLINE; then + objtoolopt="${objtoolopt} --retpoline" + fi + + if is_enabled CONFIG_SLS; then + objtoolopt="${objtoolopt} --sls" + fi + if is_enabled CONFIG_STACK_VALIDATION; then objtoolopt="${objtoolopt} --stackval" fi + if is_enabled CONFIG_X86_SMAP; then + objtoolopt="${objtoolopt} --uaccess" + fi + + objtoolopt="${objtoolopt} --lto" fi @@ -139,18 +155,6 @@ objtool_link() if [ -n "${objtoolopt}" ]; then - if is_enabled CONFIG_RETPOLINE; then - objtoolopt="${objtoolopt} --retpoline" - fi - - if is_enabled CONFIG_SLS; then - objtoolopt="${objtoolopt} --sls" - fi - - if is_enabled CONFIG_X86_SMAP; then - objtoolopt="${objtoolopt} --uaccess" - fi - if ! is_enabled CONFIG_FRAME_POINTER; then objtoolopt="${objtoolopt} --no-fp" fi -- cgit From 72064474964724c59ddff58a581a31b1ede75cf9 Mon Sep 17 00:00:00 2001 From: Josh Poimboeuf Date: Mon, 18 Apr 2022 09:50:37 -0700 Subject: objtool: Make stack validation frame-pointer-specific Now that CONFIG_STACK_VALIDATION is frame-pointer specific, do the same for the '--stackval' option. Now the '--no-fp' option is redundant and can be removed. Signed-off-by: Josh Poimboeuf Signed-off-by: Peter Zijlstra (Intel) Reviewed-by: Miroslav Benes Link: https://lkml.kernel.org/r/f563fa064b3b63d528de250c72012d49e14742a3.1650300597.git.jpoimboe@redhat.com --- scripts/link-vmlinux.sh | 4 ---- 1 file changed, 4 deletions(-) (limited to 'scripts/link-vmlinux.sh') diff --git a/scripts/link-vmlinux.sh b/scripts/link-vmlinux.sh index 5101a7fbfaaf..1be01163a9c5 100755 --- a/scripts/link-vmlinux.sh +++ b/scripts/link-vmlinux.sh @@ -155,10 +155,6 @@ objtool_link() if [ -n "${objtoolopt}" ]; then - if ! is_enabled CONFIG_FRAME_POINTER; then - objtoolopt="${objtoolopt} --no-fp" - fi - if is_enabled CONFIG_GCOV_KERNEL; then objtoolopt="${objtoolopt} --no-unreachable" fi -- cgit From 26e176896a5bb9222ae3433da902edd2566a61a4 Mon Sep 17 00:00:00 2001 From: Josh Poimboeuf Date: Mon, 18 Apr 2022 09:50:38 -0700 Subject: objtool: Make static call annotation optional As part of making objtool more modular, put the existing static call code behind a new '--static-call' option. Signed-off-by: Josh Poimboeuf Signed-off-by: Peter Zijlstra (Intel) Reviewed-by: Miroslav Benes Link: https://lkml.kernel.org/r/d59ac57ef3d6d8380cdce20322314c9e2e556750.1650300597.git.jpoimboe@redhat.com --- scripts/link-vmlinux.sh | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) (limited to 'scripts/link-vmlinux.sh') diff --git a/scripts/link-vmlinux.sh b/scripts/link-vmlinux.sh index 1be01163a9c5..33f14fe1ddde 100755 --- a/scripts/link-vmlinux.sh +++ b/scripts/link-vmlinux.sh @@ -141,11 +141,14 @@ objtool_link() objtoolopt="${objtoolopt} --stackval" fi + if is_enabled CONFIG_HAVE_STATIC_CALL_INLINE; then + objtoolopt="${objtoolopt} --static-call" + fi + if is_enabled CONFIG_X86_SMAP; then objtoolopt="${objtoolopt} --uaccess" fi - objtoolopt="${objtoolopt} --lto" fi -- cgit From 4ab7674f5951ac6a8ac4fa8828090edb64a4771f Mon Sep 17 00:00:00 2001 From: Josh Poimboeuf Date: Mon, 18 Apr 2022 09:50:39 -0700 Subject: objtool: Make jump label hack optional Objtool secretly does a jump label hack to overcome the limitations of the toolchain. Make the hack explicit (and optional for other arches) by turning it into a cmdline option and kernel config option. Signed-off-by: Josh Poimboeuf Signed-off-by: Peter Zijlstra (Intel) Reviewed-by: Miroslav Benes Link: https://lkml.kernel.org/r/3bdcbfdd27ecb01ddec13c04bdf756a583b13d24.1650300597.git.jpoimboe@redhat.com --- scripts/link-vmlinux.sh | 4 ++++ 1 file changed, 4 insertions(+) (limited to 'scripts/link-vmlinux.sh') diff --git a/scripts/link-vmlinux.sh b/scripts/link-vmlinux.sh index 33f14fe1ddde..fa1f16840e76 100755 --- a/scripts/link-vmlinux.sh +++ b/scripts/link-vmlinux.sh @@ -117,6 +117,10 @@ objtool_link() # Don't perform vmlinux validation unless explicitly requested, # but run objtool on vmlinux.o now that we have an object file. + if is_enabled CONFIG_HAVE_JUMP_LABEL_HACK; then + objtoolopt="${objtoolopt} --hacks=jump_label" + fi + if is_enabled CONFIG_X86_KERNEL_IBT; then objtoolopt="${objtoolopt} --ibt" fi -- cgit From 22102f4559beaabcea614b29ee090c6a214f002f Mon Sep 17 00:00:00 2001 From: Josh Poimboeuf Date: Mon, 18 Apr 2022 09:50:40 -0700 Subject: objtool: Make noinstr hacks optional Objtool has some hacks in place to workaround toolchain limitations which otherwise would break no-instrumentation rules. Make the hacks explicit (and optional for other arches) by turning it into a cmdline option and kernel config option. Signed-off-by: Josh Poimboeuf Signed-off-by: Peter Zijlstra (Intel) Reviewed-by: Miroslav Benes Link: https://lkml.kernel.org/r/b326eeb9c33231b9dfbb925f194ed7ee40edcd7c.1650300597.git.jpoimboe@redhat.com --- scripts/link-vmlinux.sh | 4 ++++ 1 file changed, 4 insertions(+) (limited to 'scripts/link-vmlinux.sh') diff --git a/scripts/link-vmlinux.sh b/scripts/link-vmlinux.sh index fa1f16840e76..90c9c4c05d95 100755 --- a/scripts/link-vmlinux.sh +++ b/scripts/link-vmlinux.sh @@ -121,6 +121,10 @@ objtool_link() objtoolopt="${objtoolopt} --hacks=jump_label" fi + if is_enabled CONFIG_HAVE_NOINSTR_HACK; then + objtoolopt="${objtoolopt} --hacks=noinstr" + fi + if is_enabled CONFIG_X86_KERNEL_IBT; then objtoolopt="${objtoolopt} --ibt" fi -- cgit From 0f620cefd7753175b6258fed85f76c2014ec3799 Mon Sep 17 00:00:00 2001 From: Josh Poimboeuf Date: Mon, 18 Apr 2022 09:50:41 -0700 Subject: objtool: Rename "VMLINUX_VALIDATION" -> "NOINSTR_VALIDATION" CONFIG_VMLINUX_VALIDATION is just the validation of the "noinstr" rules. That name is a misnomer, because now objtool actually does vmlinux validation for other reasons. Rename CONFIG_VMLINUX_VALIDATION to CONFIG_NOINSTR_VALIDATION. Signed-off-by: Josh Poimboeuf Signed-off-by: Peter Zijlstra (Intel) Reviewed-by: Miroslav Benes Link: https://lkml.kernel.org/r/173f07e2d6d1afc0874aed975a61783207c6a531.1650300597.git.jpoimboe@redhat.com --- scripts/link-vmlinux.sh | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'scripts/link-vmlinux.sh') diff --git a/scripts/link-vmlinux.sh b/scripts/link-vmlinux.sh index 90c9c4c05d95..fce4f41816cd 100755 --- a/scripts/link-vmlinux.sh +++ b/scripts/link-vmlinux.sh @@ -160,7 +160,7 @@ objtool_link() objtoolopt="${objtoolopt} --lto" fi - if is_enabled CONFIG_VMLINUX_VALIDATION; then + if is_enabled CONFIG_NOINSTR_VALIDATION; then objtoolopt="${objtoolopt} --noinstr" fi -- cgit From 753da4179d08b625d8df72e97724e22749969fd3 Mon Sep 17 00:00:00 2001 From: Josh Poimboeuf Date: Mon, 18 Apr 2022 09:50:43 -0700 Subject: objtool: Remove --lto and --vmlinux in favor of --link The '--lto' option is a confusing way of telling objtool to do stack validation despite it being a linked object. It's no longer needed now that an explicit '--stackval' option exists. The '--vmlinux' option is also redundant. Remove both options in favor of a straightforward '--link' option which identifies a linked object. Also, implicitly set '--link' with a warning if the user forgets to do so and we can tell that it's a linked object. This makes it easier for manual vmlinux runs. Signed-off-by: Josh Poimboeuf Signed-off-by: Peter Zijlstra (Intel) Reviewed-by: Miroslav Benes Link: https://lkml.kernel.org/r/dcd3ceffd15a54822c6183e5766d21ad06082b45.1650300597.git.jpoimboe@redhat.com --- scripts/link-vmlinux.sh | 8 +++----- 1 file changed, 3 insertions(+), 5 deletions(-) (limited to 'scripts/link-vmlinux.sh') diff --git a/scripts/link-vmlinux.sh b/scripts/link-vmlinux.sh index fce4f41816cd..eb9324f07f3d 100755 --- a/scripts/link-vmlinux.sh +++ b/scripts/link-vmlinux.sh @@ -114,8 +114,8 @@ objtool_link() if is_enabled CONFIG_LTO_CLANG || is_enabled CONFIG_X86_KERNEL_IBT; then - # Don't perform vmlinux validation unless explicitly requested, - # but run objtool on vmlinux.o now that we have an object file. + # For LTO and IBT, objtool doesn't run on individual + # translation units. Run everything on vmlinux instead. if is_enabled CONFIG_HAVE_JUMP_LABEL_HACK; then objtoolopt="${objtoolopt} --hacks=jump_label" @@ -156,8 +156,6 @@ objtool_link() if is_enabled CONFIG_X86_SMAP; then objtoolopt="${objtoolopt} --uaccess" fi - - objtoolopt="${objtoolopt} --lto" fi if is_enabled CONFIG_NOINSTR_VALIDATION; then @@ -170,7 +168,7 @@ objtool_link() objtoolopt="${objtoolopt} --no-unreachable" fi - objtoolopt="${objtoolopt} --vmlinux" + objtoolopt="${objtoolopt} --link" info OBJTOOL ${1} tools/objtool/objtool ${objtoolopt} ${1} -- cgit From e493f472752000968f5b30aac10391288cfbf5b1 Mon Sep 17 00:00:00 2001 From: Masahiro Yamada Date: Thu, 5 May 2022 16:22:34 +0900 Subject: kbuild: generate a list of objects in vmlinux A *.mod file lists the member objects of a module, but vmlinux does not have such a file. Generate this list to allow modpost to know all the member objects. Signed-off-by: Masahiro Yamada Reviewed-by: Nicolas Schier Tested-by: Nathan Chancellor --- scripts/link-vmlinux.sh | 11 +++++++++++ 1 file changed, 11 insertions(+) (limited to 'scripts/link-vmlinux.sh') diff --git a/scripts/link-vmlinux.sh b/scripts/link-vmlinux.sh index 20f44504a644..eceb3ee7ec06 100755 --- a/scripts/link-vmlinux.sh +++ b/scripts/link-vmlinux.sh @@ -311,6 +311,7 @@ cleanup() rm -f vmlinux.map rm -f vmlinux.o rm -f .vmlinux.d + rm -f .vmlinux.objs } # Use "make V=1" to debug this script @@ -342,6 +343,16 @@ ${MAKE} -f "${srctree}/scripts/Makefile.build" obj=init need-builtin=1 modpost_link vmlinux.o objtool_link vmlinux.o +# Generate the list of objects in vmlinux +for f in ${KBUILD_VMLINUX_OBJS} ${KBUILD_VMLINUX_LIBS}; do + case ${f} in + *.a) + ${AR} t ${f} ;; + *) + echo ${f} ;; + esac +done > .vmlinux.objs + # modpost vmlinux.o to check for section mismatches ${MAKE} -f "${srctree}/scripts/Makefile.modpost" MODPOST_VMLINUX=1 -- cgit From 7b4537199a4a8480b8c3ba37a2d44765ce76cd9b Mon Sep 17 00:00:00 2001 From: Masahiro Yamada Date: Fri, 13 May 2022 20:39:22 +0900 Subject: kbuild: link symbol CRCs at final link, removing CONFIG_MODULE_REL_CRCS include/{linux,asm-generic}/export.h defines a weak symbol, __crc_* as a placeholder. Genksyms writes the version CRCs into the linker script, which will be used for filling the __crc_* symbols. The linker script format depends on CONFIG_MODULE_REL_CRCS. If it is enabled, __crc_* holds the offset to the reference of CRC. It is time to get rid of this complexity. Now that modpost parses text files (.*.cmd) to collect all the CRCs, it can generate C code that will be linked to the vmlinux or modules. Generate a new C file, .vmlinux.export.c, which contains the CRCs of symbols exported by vmlinux. It is compiled and linked to vmlinux in scripts/link-vmlinux.sh. Put the CRCs of symbols exported by modules into the existing *.mod.c files. No additional build step is needed for modules. As before, *.mod.c are compiled and linked to *.ko in scripts/Makefile.modfinal. No linker magic is used here. The new C implementation works in the same way, whether CONFIG_RELOCATABLE is enabled or not. CONFIG_MODULE_REL_CRCS is no longer needed. Previously, Kbuild invoked additional $(LD) to update the CRCs in objects, but this step is unneeded too. Signed-off-by: Masahiro Yamada Tested-by: Nathan Chancellor Tested-by: Nicolas Schier Reviewed-by: Nicolas Schier Tested-by: Sedat Dilek # LLVM-14 (x86-64) --- scripts/link-vmlinux.sh | 10 +++++++++- 1 file changed, 9 insertions(+), 1 deletion(-) (limited to 'scripts/link-vmlinux.sh') diff --git a/scripts/link-vmlinux.sh b/scripts/link-vmlinux.sh index eceb3ee7ec06..db34dc3163ae 100755 --- a/scripts/link-vmlinux.sh +++ b/scripts/link-vmlinux.sh @@ -90,7 +90,6 @@ modpost_link() if is_enabled CONFIG_MODVERSIONS; then gen_symversions - lds="${lds} -T .tmp_symversions.lds" fi # This might take a while, so indicate that we're doing @@ -183,6 +182,10 @@ vmlinux_link() libs="${KBUILD_VMLINUX_LIBS}" fi + if is_enabled CONFIG_MODULES; then + objs="${objs} .vmlinux.export.o" + fi + if [ "${SRCARCH}" = "um" ]; then wl=-Wl, ld="${CC}" @@ -312,6 +315,7 @@ cleanup() rm -f vmlinux.o rm -f .vmlinux.d rm -f .vmlinux.objs + rm -f .vmlinux.export.c } # Use "make V=1" to debug this script @@ -363,6 +367,10 @@ info GEN modules.builtin tr '\0' '\n' < modules.builtin.modinfo | sed -n 's/^[[:alnum:]:_]*\.file=//p' | tr ' ' '\n' | uniq | sed -e 's:^:kernel/:' -e 's/$/.ko/' > modules.builtin +if is_enabled CONFIG_MODULES; then + ${MAKE} -f "${srctree}/scripts/Makefile.vmlinux" .vmlinux.export.o +fi + btf_vmlinux_bin_o="" if is_enabled CONFIG_DEBUG_INFO_BTF; then btf_vmlinux_bin_o=.btf.vmlinux.bin.o -- cgit From 7375cbcf2343a9337b19846e76dfd94c3af98a27 Mon Sep 17 00:00:00 2001 From: Masahiro Yamada Date: Fri, 13 May 2022 20:39:23 +0900 Subject: kbuild: stop merging *.symversions Now modpost reads symbol versions from .*.cmd files. The merged *.symversions are no longer needed. Signed-off-by: Masahiro Yamada Reviewed-by: Nicolas Schier Tested-by: Nathan Chancellor Tested-by: Sedat Dilek # LLVM-14 (x86-64) --- scripts/link-vmlinux.sh | 19 ------------------- 1 file changed, 19 deletions(-) (limited to 'scripts/link-vmlinux.sh') diff --git a/scripts/link-vmlinux.sh b/scripts/link-vmlinux.sh index db34dc3163ae..eb6721e2fc47 100755 --- a/scripts/link-vmlinux.sh +++ b/scripts/link-vmlinux.sh @@ -56,20 +56,6 @@ gen_initcalls() > .tmp_initcalls.lds } -# If CONFIG_LTO_CLANG is selected, collect generated symbol versions into -# .tmp_symversions.lds -gen_symversions() -{ - info GEN .tmp_symversions.lds - rm -f .tmp_symversions.lds - - for o in ${KBUILD_VMLINUX_OBJS} ${KBUILD_VMLINUX_LIBS}; do - if [ -f ${o}.symversions ]; then - cat ${o}.symversions >> .tmp_symversions.lds - fi - done -} - # Link of vmlinux.o used for section mismatch analysis # ${1} output file modpost_link() @@ -88,10 +74,6 @@ modpost_link() gen_initcalls lds="-T .tmp_initcalls.lds" - if is_enabled CONFIG_MODVERSIONS; then - gen_symversions - fi - # This might take a while, so indicate that we're doing # an LTO link info LTO ${1} @@ -307,7 +289,6 @@ cleanup() rm -f .btf.* rm -f .tmp_System.map rm -f .tmp_initcalls.lds - rm -f .tmp_symversions.lds rm -f .tmp_vmlinux* rm -f System.map rm -f vmlinux -- cgit From 0aa24a79ee3b603f6e6cd470c364edc2d746f613 Mon Sep 17 00:00:00 2001 From: Masahiro Yamada Date: Sun, 29 May 2022 13:23:18 +0900 Subject: kbuild: do not try to parse *.cmd files for objects provided by compiler Guenter Roeck reported the build breakage for parisc and csky. I confirmed nios2 and openrisc are broken as well. The reason is that they borrow libgcc.a from the toolchains. For example, see this line in arch/parisc/Makefile: LIBGCC := $(shell $(CC) -print-libgcc-file-name) Some objects in libgcc.a are linked to vmlinux.o, but they do not have .*.cmd files. Obviously, there is no EXPORT_SYMBOL in external objects. Ignore them. (Most of the architectures import library code into the kernel tree. Perhaps those 4 architectures can do similar, but I do not know how challenging it is.) Fixes: f292d875d0dc ("modpost: extract symbol versions from *.cmd files") Link: https://lore.kernel.org/linux-kbuild/20220528224745.GA2501857@roeck-us.net/T/#mac65c20c71c3e272db0350ecfba53fcd8905b0a0 Reported-by: Guenter Roeck Signed-off-by: Masahiro Yamada Tested-by: Guenter Roeck --- scripts/link-vmlinux.sh | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-) (limited to 'scripts/link-vmlinux.sh') diff --git a/scripts/link-vmlinux.sh b/scripts/link-vmlinux.sh index a7f6196c7e41..68e4be463a76 100755 --- a/scripts/link-vmlinux.sh +++ b/scripts/link-vmlinux.sh @@ -344,9 +344,16 @@ ${MAKE} -f "${srctree}/scripts/Makefile.build" obj=init need-builtin=1 modpost_link vmlinux.o objtool_link vmlinux.o -# Generate the list of objects in vmlinux +# Generate the list of in-tree objects in vmlinux +# +# This is used to retrieve symbol versions generated by genksyms. for f in ${KBUILD_VMLINUX_OBJS} ${KBUILD_VMLINUX_LIBS}; do case ${f} in + *libgcc.a) + # Some architectures do '$(CC) --print-libgcc-file-name' to + # borrow libgcc.a from the toolchain. + # There is no EXPORT_SYMBOL in external objects. Ignore this. + ;; *.a) ${AR} t ${f} ;; *) -- cgit From a78b6afa9913890e92aede1c17e72dec7e528549 Mon Sep 17 00:00:00 2001 From: Masahiro Yamada Date: Sun, 29 May 2022 00:47:01 +0900 Subject: kbuild: remove redundant cleanups in scripts/link-vmlinux.sh These are cleaned by the top Makefile. vmlinux.o and .vmlinux.d matches the '*.[aios]' and '.*.d' patterns respectively. Signed-off-by: Masahiro Yamada Tested-by: Sedat Dilek # LLVM-14 (x86-64) --- scripts/link-vmlinux.sh | 2 -- 1 file changed, 2 deletions(-) (limited to 'scripts/link-vmlinux.sh') diff --git a/scripts/link-vmlinux.sh b/scripts/link-vmlinux.sh index 68e4be463a76..1c0af7288b79 100755 --- a/scripts/link-vmlinux.sh +++ b/scripts/link-vmlinux.sh @@ -309,8 +309,6 @@ cleanup() rm -f System.map rm -f vmlinux rm -f vmlinux.map - rm -f vmlinux.o - rm -f .vmlinux.d rm -f .vmlinux.objs rm -f .vmlinux.export.c } -- cgit From b0d6207bad2cb5a6f2099ac4a6ea4e76864dd596 Mon Sep 17 00:00:00 2001 From: Masahiro Yamada Date: Sun, 29 May 2022 00:47:02 +0900 Subject: kbuild: clean .tmp_* pattern by make clean Change the "make clean" rule to remove all the .tmp_* files. .tmp_objdiff is the only exception, which should be removed by "make mrproper". Rename the record directory of objdiff, .tmp_objdiff to .objdiff to avoid the removal by "make clean". Signed-off-by: Masahiro Yamada Tested-by: Sedat Dilek # LLVM-14 (x86-64) --- scripts/link-vmlinux.sh | 3 --- 1 file changed, 3 deletions(-) (limited to 'scripts/link-vmlinux.sh') diff --git a/scripts/link-vmlinux.sh b/scripts/link-vmlinux.sh index 1c0af7288b79..3f51b08cc203 100755 --- a/scripts/link-vmlinux.sh +++ b/scripts/link-vmlinux.sh @@ -303,9 +303,6 @@ sorttable() cleanup() { rm -f .btf.* - rm -f .tmp_System.map - rm -f .tmp_initcalls.lds - rm -f .tmp_vmlinux* rm -f System.map rm -f vmlinux rm -f vmlinux.map -- cgit From 5d45950dfbb1540bba3e3762a3497de8b4a715d3 Mon Sep 17 00:00:00 2001 From: Masahiro Yamada Date: Sun, 29 May 2022 00:47:03 +0900 Subject: kbuild: move vmlinux.o link to scripts/Makefile.vmlinux_o This is a preparation for moving the objtool rule in the next commit. Signed-off-by: Masahiro Yamada Tested-by: Sedat Dilek # LLVM-14 (x86-64) --- scripts/link-vmlinux.sh | 41 +---------------------------------------- 1 file changed, 1 insertion(+), 40 deletions(-) (limited to 'scripts/link-vmlinux.sh') diff --git a/scripts/link-vmlinux.sh b/scripts/link-vmlinux.sh index 3f51b08cc203..bf685d4547c1 100755 --- a/scripts/link-vmlinux.sh +++ b/scripts/link-vmlinux.sh @@ -45,45 +45,6 @@ info() printf " %-7s %s\n" "${1}" "${2}" } -# Generate a linker script to ensure correct ordering of initcalls. -gen_initcalls() -{ - info GEN .tmp_initcalls.lds - - ${PYTHON3} ${srctree}/scripts/jobserver-exec \ - ${PERL} ${srctree}/scripts/generate_initcall_order.pl \ - ${KBUILD_VMLINUX_OBJS} ${KBUILD_VMLINUX_LIBS} \ - > .tmp_initcalls.lds -} - -# Link of vmlinux.o used for section mismatch analysis -# ${1} output file -modpost_link() -{ - local objects - local lds="" - - objects="--whole-archive \ - ${KBUILD_VMLINUX_OBJS} \ - --no-whole-archive \ - --start-group \ - ${KBUILD_VMLINUX_LIBS} \ - --end-group" - - if is_enabled CONFIG_LTO_CLANG; then - gen_initcalls - lds="-T .tmp_initcalls.lds" - - # This might take a while, so indicate that we're doing - # an LTO link - info LTO ${1} - else - info LD ${1} - fi - - ${LD} ${KBUILD_LDFLAGS} -r -o ${1} ${lds} ${objects} -} - objtool_link() { local objtoolcmd; @@ -336,7 +297,7 @@ fi; ${MAKE} -f "${srctree}/scripts/Makefile.build" obj=init need-builtin=1 #link vmlinux.o -modpost_link vmlinux.o +${MAKE} -f "${srctree}/scripts/Makefile.vmlinux_o" objtool_link vmlinux.o # Generate the list of in-tree objects in vmlinux -- cgit From b42d2306502419688190aa6dd4dab4a6def24b3d Mon Sep 17 00:00:00 2001 From: Masahiro Yamada Date: Sun, 29 May 2022 00:47:04 +0900 Subject: kbuild: factor out the common objtool arguments scripts/Makefile.build and scripts/link-vmlinux.sh have similar setups for the objtool arguments. It was difficult to factor out them because all the vmlinux build rules were written in a shell script. It is somewhat tedious to touch the two files every time a new objtool option is supported. To reduce the code duplication, move the objtool for vmlinux.o into scripts/Makefile.vmlinux_o. Then, move the common macros to Makefile.lib so they are shared between Makefile.build and Makefile.vmlinux_o. Signed-off-by: Masahiro Yamada Tested-by: Sedat Dilek # LLVM-14 (x86-64) --- scripts/link-vmlinux.sh | 71 ------------------------------------------------- 1 file changed, 71 deletions(-) (limited to 'scripts/link-vmlinux.sh') diff --git a/scripts/link-vmlinux.sh b/scripts/link-vmlinux.sh index bf685d4547c1..eecc1863e556 100755 --- a/scripts/link-vmlinux.sh +++ b/scripts/link-vmlinux.sh @@ -45,76 +45,6 @@ info() printf " %-7s %s\n" "${1}" "${2}" } -objtool_link() -{ - local objtoolcmd; - local objtoolopt; - - if ! is_enabled CONFIG_OBJTOOL; then - return; - fi - - if is_enabled CONFIG_LTO_CLANG || is_enabled CONFIG_X86_KERNEL_IBT; then - - # For LTO and IBT, objtool doesn't run on individual - # translation units. Run everything on vmlinux instead. - - if is_enabled CONFIG_HAVE_JUMP_LABEL_HACK; then - objtoolopt="${objtoolopt} --hacks=jump_label" - fi - - if is_enabled CONFIG_HAVE_NOINSTR_HACK; then - objtoolopt="${objtoolopt} --hacks=noinstr" - fi - - if is_enabled CONFIG_X86_KERNEL_IBT; then - objtoolopt="${objtoolopt} --ibt" - fi - - if is_enabled CONFIG_FTRACE_MCOUNT_USE_OBJTOOL; then - objtoolopt="${objtoolopt} --mcount" - fi - - if is_enabled CONFIG_UNWINDER_ORC; then - objtoolopt="${objtoolopt} --orc" - fi - - if is_enabled CONFIG_RETPOLINE; then - objtoolopt="${objtoolopt} --retpoline" - fi - - if is_enabled CONFIG_SLS; then - objtoolopt="${objtoolopt} --sls" - fi - - if is_enabled CONFIG_STACK_VALIDATION; then - objtoolopt="${objtoolopt} --stackval" - fi - - if is_enabled CONFIG_HAVE_STATIC_CALL_INLINE; then - objtoolopt="${objtoolopt} --static-call" - fi - - objtoolopt="${objtoolopt} --uaccess" - fi - - if is_enabled CONFIG_NOINSTR_VALIDATION; then - objtoolopt="${objtoolopt} --noinstr" - fi - - if [ -n "${objtoolopt}" ]; then - - if is_enabled CONFIG_GCOV_KERNEL; then - objtoolopt="${objtoolopt} --no-unreachable" - fi - - objtoolopt="${objtoolopt} --link" - - info OBJTOOL ${1} - tools/objtool/objtool ${objtoolopt} ${1} - fi -} - # Link of vmlinux # ${1} - output file # ${2}, ${3}, ... - optional extra .o files @@ -298,7 +228,6 @@ ${MAKE} -f "${srctree}/scripts/Makefile.build" obj=init need-builtin=1 #link vmlinux.o ${MAKE} -f "${srctree}/scripts/Makefile.vmlinux_o" -objtool_link vmlinux.o # Generate the list of in-tree objects in vmlinux # -- cgit From 2df8220cc511326508ec4da2f43ef69311bdd7b9 Mon Sep 17 00:00:00 2001 From: Masahiro Yamada Date: Sun, 28 Aug 2022 11:39:53 +0900 Subject: kbuild: build init/built-in.a just once Kbuild builds init/built-in.a twice; first during the ordinary directory descending, second from scripts/link-vmlinux.sh. We do this because UTS_VERSION contains the build version and the timestamp. We cannot update it during the normal directory traversal since we do not yet know if we need to update vmlinux. UTS_VERSION is temporarily calculated, but omitted from the update check. Otherwise, vmlinux would be rebuilt every time. When Kbuild results in running link-vmlinux.sh, it increments the version number in the .version file and takes the timestamp at that time to really fix UTS_VERSION. However, updating the same file twice is a footgun. To avoid nasty timestamp issues, all build artifacts that depend on init/built-in.a are atomically generated in link-vmlinux.sh, where some of them do not need rebuilding. To fix this issue, this commit changes as follows: [1] Split UTS_VERSION out to include/generated/utsversion.h from include/generated/compile.h include/generated/utsversion.h is generated just before the vmlinux link. It is generated under include/generated/ because some decompressors (s390, x86) use UTS_VERSION. [2] Split init_uts_ns and linux_banner out to init/version-timestamp.c from init/version.c init_uts_ns and linux_banner contain UTS_VERSION. During the ordinary directory descending, they are compiled with __weak and used to determine if vmlinux needs relinking. Just before the vmlinux link, they are compiled without __weak to embed the real version and timestamp. Signed-off-by: Masahiro Yamada --- scripts/link-vmlinux.sh | 17 ++++------------- 1 file changed, 4 insertions(+), 13 deletions(-) (limited to 'scripts/link-vmlinux.sh') diff --git a/scripts/link-vmlinux.sh b/scripts/link-vmlinux.sh index eecc1863e556..8d982574145a 100755 --- a/scripts/link-vmlinux.sh +++ b/scripts/link-vmlinux.sh @@ -75,6 +75,8 @@ vmlinux_link() objs="${objs} .vmlinux.export.o" fi + objs="${objs} init/version-timestamp.o" + if [ "${SRCARCH}" = "um" ]; then wl=-Wl, ld="${CC}" @@ -213,19 +215,6 @@ if [ "$1" = "clean" ]; then exit 0 fi -# Update version -info GEN .version -if [ -r .version ]; then - VERSION=$(expr 0$(cat .version) + 1) - echo $VERSION > .version -else - rm -f .version - echo 1 > .version -fi; - -# final build of init/ -${MAKE} -f "${srctree}/scripts/Makefile.build" obj=init need-builtin=1 - #link vmlinux.o ${MAKE} -f "${srctree}/scripts/Makefile.vmlinux_o" @@ -260,6 +249,8 @@ if is_enabled CONFIG_MODULES; then ${MAKE} -f "${srctree}/scripts/Makefile.vmlinux" .vmlinux.export.o fi +${MAKE} -f "${srctree}/scripts/Makefile.build" obj=init init/version-timestamp.o + btf_vmlinux_bin_o="" if is_enabled CONFIG_DEBUG_INFO_BTF; then btf_vmlinux_bin_o=.btf.vmlinux.bin.o -- cgit From 26ef40de5cbb24728a34a319e8d42cdec99f186c Mon Sep 17 00:00:00 2001 From: Masahiro Yamada Date: Sun, 25 Sep 2022 03:19:11 +0900 Subject: kbuild: move .vmlinux.objs rule to Makefile.modpost .vmlinux.objs is used by modpost, so scripts/Makefile.modpost is a better place to generate it. It is used only when CONFIG_MODVERSIONS=y. It should be guarded by "ifdef CONFIG_MODVERSIONS". Signed-off-by: Masahiro Yamada Tested-by: Nick Desaulniers Reviewed-by: Nicolas Schier --- scripts/link-vmlinux.sh | 18 ------------------ 1 file changed, 18 deletions(-) (limited to 'scripts/link-vmlinux.sh') diff --git a/scripts/link-vmlinux.sh b/scripts/link-vmlinux.sh index 8d982574145a..161bca64e8aa 100755 --- a/scripts/link-vmlinux.sh +++ b/scripts/link-vmlinux.sh @@ -199,7 +199,6 @@ cleanup() rm -f System.map rm -f vmlinux rm -f vmlinux.map - rm -f .vmlinux.objs rm -f .vmlinux.export.c } @@ -218,23 +217,6 @@ fi #link vmlinux.o ${MAKE} -f "${srctree}/scripts/Makefile.vmlinux_o" -# Generate the list of in-tree objects in vmlinux -# -# This is used to retrieve symbol versions generated by genksyms. -for f in ${KBUILD_VMLINUX_OBJS} ${KBUILD_VMLINUX_LIBS}; do - case ${f} in - *libgcc.a) - # Some architectures do '$(CC) --print-libgcc-file-name' to - # borrow libgcc.a from the toolchain. - # There is no EXPORT_SYMBOL in external objects. Ignore this. - ;; - *.a) - ${AR} t ${f} ;; - *) - echo ${f} ;; - esac -done > .vmlinux.objs - # modpost vmlinux.o to check for section mismatches ${MAKE} -f "${srctree}/scripts/Makefile.modpost" MODPOST_VMLINUX=1 -- cgit From 9c5a0ac3c36917c4258f734bda98be02ca36b992 Mon Sep 17 00:00:00 2001 From: Masahiro Yamada Date: Sun, 25 Sep 2022 03:19:12 +0900 Subject: kbuild: move vmlinux.o rule to the top Makefile Move the build rules of vmlinux.o out of scripts/link-vmlinux.sh to clearly separate 1) pre-modpost, 2) modpost, 3) post-modpost stages. This will make further refactoring possible. Signed-off-by: Masahiro Yamada Tested-by: Nick Desaulniers Reviewed-by: Nicolas Schier --- scripts/link-vmlinux.sh | 3 --- 1 file changed, 3 deletions(-) (limited to 'scripts/link-vmlinux.sh') diff --git a/scripts/link-vmlinux.sh b/scripts/link-vmlinux.sh index 161bca64e8aa..07486f90d5e2 100755 --- a/scripts/link-vmlinux.sh +++ b/scripts/link-vmlinux.sh @@ -214,9 +214,6 @@ if [ "$1" = "clean" ]; then exit 0 fi -#link vmlinux.o -${MAKE} -f "${srctree}/scripts/Makefile.vmlinux_o" - # modpost vmlinux.o to check for section mismatches ${MAKE} -f "${srctree}/scripts/Makefile.modpost" MODPOST_VMLINUX=1 -- cgit From f73edc8951b2de515b5ecc8a357ccd47dd41077e Mon Sep 17 00:00:00 2001 From: Masahiro Yamada Date: Sun, 25 Sep 2022 03:19:13 +0900 Subject: kbuild: unify two modpost invocations Currently, modpost is executed twice; first for vmlinux, second for modules. This commit merges them. Current build flow ================== 1) build obj-y and obj-m objects 2) link vmlinux.o 3) modpost for vmlinux 4) link vmlinux 5) modpost for modules 6) link modules (*.ko) The build steps 1) through 6) are serialized, that is, modules are built after vmlinux. You do not get benefits of parallel builds when scripts/link-vmlinux.sh is being run. New build flow ============== 1) build obj-y and obj-m objects 2) link vmlinux.o 3) modpost for vmlinux and modules 4a) link vmlinux 4b) link modules (*.ko) In the new build flow, modpost is invoked just once. vmlinux and modules are built in parallel. One exception is CONFIG_DEBUG_INFO_BTF_MODULES=y, where modules depend on vmlinux. Signed-off-by: Masahiro Yamada Tested-by: Nick Desaulniers Reviewed-by: Nicolas Schier --- scripts/link-vmlinux.sh | 3 --- 1 file changed, 3 deletions(-) (limited to 'scripts/link-vmlinux.sh') diff --git a/scripts/link-vmlinux.sh b/scripts/link-vmlinux.sh index 07486f90d5e2..6a197d8a88ac 100755 --- a/scripts/link-vmlinux.sh +++ b/scripts/link-vmlinux.sh @@ -214,9 +214,6 @@ if [ "$1" = "clean" ]; then exit 0 fi -# modpost vmlinux.o to check for section mismatches -${MAKE} -f "${srctree}/scripts/Makefile.modpost" MODPOST_VMLINUX=1 - info MODINFO modules.builtin.modinfo ${OBJCOPY} -j .modinfo -O binary vmlinux.o modules.builtin.modinfo info GEN modules.builtin -- cgit From 3216484550610470013b7ce1c9ed272da0a74589 Mon Sep 17 00:00:00 2001 From: Masahiro Yamada Date: Sun, 25 Sep 2022 03:19:14 +0900 Subject: kbuild: use obj-y instead extra-y for objects placed at the head The objects placed at the head of vmlinux need special treatments: - arch/$(SRCARCH)/Makefile adds them to head-y in order to place them before other archives in the linker command line. - arch/$(SRCARCH)/kernel/Makefile adds them to extra-y instead of obj-y to avoid them going into built-in.a. This commit gets rid of the latter. Create vmlinux.a to collect all the objects that are unconditionally linked to vmlinux. The objects listed in head-y are moved to the head of vmlinux.a by using 'ar m'. With this, arch/$(SRCARCH)/kernel/Makefile can consistently use obj-y for builtin objects. There is no *.o that is directly linked to vmlinux. Drop unneeded code in scripts/clang-tools/gen_compile_commands.py. $(AR) mPi needs 'T' to workaround the llvm-ar bug. The fix was suggested by Nathan Chancellor [1]. [1]: https://lore.kernel.org/llvm/YyjjT5gQ2hGMH0ni@dev-arch.thelio-3990X/ Signed-off-by: Masahiro Yamada Tested-by: Nick Desaulniers Reviewed-by: Nicolas Schier --- scripts/link-vmlinux.sh | 10 ++++------ 1 file changed, 4 insertions(+), 6 deletions(-) (limited to 'scripts/link-vmlinux.sh') diff --git a/scripts/link-vmlinux.sh b/scripts/link-vmlinux.sh index 6a197d8a88ac..23ac13fd9d89 100755 --- a/scripts/link-vmlinux.sh +++ b/scripts/link-vmlinux.sh @@ -3,17 +3,15 @@ # # link vmlinux # -# vmlinux is linked from the objects selected by $(KBUILD_VMLINUX_OBJS) and -# $(KBUILD_VMLINUX_LIBS). Most are built-in.a files from top-level directories -# in the kernel tree, others are specified in arch/$(ARCH)/Makefile. +# vmlinux is linked from the objects in vmlinux.a and $(KBUILD_VMLINUX_LIBS). +# vmlinux.a contains objects that are linked unconditionally. # $(KBUILD_VMLINUX_LIBS) are archives which are linked conditionally # (not within --whole-archive), and do not require symbol indexes added. # # vmlinux # ^ # | -# +--< $(KBUILD_VMLINUX_OBJS) -# | +--< init/built-in.a drivers/built-in.a mm/built-in.a + more +# +--< vmlinux.a # | # +--< $(KBUILD_VMLINUX_LIBS) # | +--< lib/lib.a + more @@ -67,7 +65,7 @@ vmlinux_link() objs=vmlinux.o libs= else - objs="${KBUILD_VMLINUX_OBJS}" + objs=vmlinux.a libs="${KBUILD_VMLINUX_LIBS}" fi -- cgit From 94ff2f63d6a31501ceb36ebc600240937cfff35f Mon Sep 17 00:00:00 2001 From: Masahiro Yamada Date: Mon, 26 Sep 2022 18:02:26 +0900 Subject: kbuild: reuse mksysmap output for kallsyms scripts/mksysmap internally runs ${NM} (dropping some symbols). When CONFIG_KALLSYMS=y, mksysmap creates .tmp_System.map, but it is almost the same as the output from the ${NM} invocation in kallsyms(). It is true scripts/mksysmap drops some symbols, but scripts/kallsyms.c ignores more anyway. Keep the mksysmap output as *.syms, and reuse it for kallsyms and 'cmp -s'. It saves one ${NM} invocation. Signed-off-by: Masahiro Yamada --- scripts/link-vmlinux.sh | 11 +++++------ 1 file changed, 5 insertions(+), 6 deletions(-) (limited to 'scripts/link-vmlinux.sh') diff --git a/scripts/link-vmlinux.sh b/scripts/link-vmlinux.sh index 23ac13fd9d89..6492c0862657 100755 --- a/scripts/link-vmlinux.sh +++ b/scripts/link-vmlinux.sh @@ -157,7 +157,7 @@ kallsyms() fi info KSYMS ${2} - ${NM} -n ${1} | scripts/kallsyms ${kallsymopt} > ${2} + cat ${1} | scripts/kallsyms ${kallsymopt} > ${2} } # Perform one step in kallsyms generation, including temporary linking of @@ -170,7 +170,8 @@ kallsyms_step() kallsyms_S=${kallsyms_vmlinux}.S vmlinux_link ${kallsyms_vmlinux} "${kallsymso_prev}" ${btf_vmlinux_bin_o} - kallsyms ${kallsyms_vmlinux} ${kallsyms_S} + mksysmap ${kallsyms_vmlinux} ${kallsyms_vmlinux}.syms + kallsyms ${kallsyms_vmlinux}.syms ${kallsyms_S} info AS ${kallsyms_S} ${CC} ${NOSTDINC_FLAGS} ${LINUXINCLUDE} ${KBUILD_CPPFLAGS} \ @@ -182,6 +183,7 @@ kallsyms_step() # See mksymap for additional details mksysmap() { + info NM ${2} ${CONFIG_SHELL} "${srctree}/scripts/mksysmap" ${1} ${2} } @@ -283,7 +285,6 @@ if is_enabled CONFIG_DEBUG_INFO_BTF && is_enabled CONFIG_BPF; then ${RESOLVE_BTFIDS} vmlinux fi -info SYSMAP System.map mksysmap vmlinux System.map if is_enabled CONFIG_BUILDTIME_TABLE_SORT; then @@ -296,9 +297,7 @@ fi # step a (see comment above) if is_enabled CONFIG_KALLSYMS; then - mksysmap ${kallsyms_vmlinux} .tmp_System.map - - if ! cmp -s System.map .tmp_System.map; then + if ! cmp -s System.map ${kallsyms_vmlinux}.syms; then echo >&2 Inconsistent kallsyms data echo >&2 Try "make KALLSYMS_EXTRA_PASS=1" as a workaround exit 1 -- cgit From aa221f2ea58655f5360e7b0c6fe5482f7c41855e Mon Sep 17 00:00:00 2001 From: Masahiro Yamada Date: Mon, 26 Sep 2022 18:02:28 +0900 Subject: kallsyms: take the input file instead of reading stdin This gets rid of the pipe operator connected with 'cat'. Also use getopt_long() to parse the command line. Signed-off-by: Masahiro Yamada --- scripts/link-vmlinux.sh | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'scripts/link-vmlinux.sh') diff --git a/scripts/link-vmlinux.sh b/scripts/link-vmlinux.sh index 6492c0862657..2782c5d1518b 100755 --- a/scripts/link-vmlinux.sh +++ b/scripts/link-vmlinux.sh @@ -157,7 +157,7 @@ kallsyms() fi info KSYMS ${2} - cat ${1} | scripts/kallsyms ${kallsymopt} > ${2} + scripts/kallsyms ${kallsymopt} ${1} > ${2} } # Perform one step in kallsyms generation, including temporary linking of -- cgit From 7a342e6c7735e13b294374cb0a0f6283d8667496 Mon Sep 17 00:00:00 2001 From: Masahiro Yamada Date: Wed, 28 Sep 2022 15:39:40 +0900 Subject: kbuild: move modules.builtin(.modinfo) rules to Makefile.vmlinux_o Do not build modules.builtin(.modinfo) as a side-effect of vmlinux. There are no good reason to rebuild them just because any of vmlinux's prerequistes (vmlinux.lds, .vmlinux.export.c, etc.) has been updated. Signed-off-by: Masahiro Yamada --- scripts/link-vmlinux.sh | 7 ------- 1 file changed, 7 deletions(-) (limited to 'scripts/link-vmlinux.sh') diff --git a/scripts/link-vmlinux.sh b/scripts/link-vmlinux.sh index 2782c5d1518b..e3d42202e54c 100755 --- a/scripts/link-vmlinux.sh +++ b/scripts/link-vmlinux.sh @@ -214,13 +214,6 @@ if [ "$1" = "clean" ]; then exit 0 fi -info MODINFO modules.builtin.modinfo -${OBJCOPY} -j .modinfo -O binary vmlinux.o modules.builtin.modinfo -info GEN modules.builtin -# The second line aids cases where multiple modules share the same object. -tr '\0' '\n' < modules.builtin.modinfo | sed -n 's/^[[:alnum:]:_]*\.file=//p' | - tr ' ' '\n' | uniq | sed -e 's:^:kernel/:' -e 's/$/.ko/' > modules.builtin - if is_enabled CONFIG_MODULES; then ${MAKE} -f "${srctree}/scripts/Makefile.vmlinux" .vmlinux.export.o fi -- cgit From 5d4aeffbf7092b6bd7b2de71c2cd6fa14dffbad5 Mon Sep 17 00:00:00 2001 From: Masahiro Yamada Date: Wed, 28 Sep 2022 15:39:41 +0900 Subject: kbuild: rebuild .vmlinux.export.o when its prerequisite is updated When include/linux/export-internal.h is updated, .vmlinux.export.o must be rebuilt, but it does not happen because its rule is hidden behind scripts/link-vmlinux.sh. Move it out of the shell script, so that Make can see the dependency between vmlinux and .vmlinux.export.o. Move the vmlinux rule to scripts/Makefile.vmlinux. Signed-off-by: Masahiro Yamada --- scripts/link-vmlinux.sh | 5 ----- 1 file changed, 5 deletions(-) (limited to 'scripts/link-vmlinux.sh') diff --git a/scripts/link-vmlinux.sh b/scripts/link-vmlinux.sh index e3d42202e54c..918470d768e9 100755 --- a/scripts/link-vmlinux.sh +++ b/scripts/link-vmlinux.sh @@ -199,7 +199,6 @@ cleanup() rm -f System.map rm -f vmlinux rm -f vmlinux.map - rm -f .vmlinux.export.c } # Use "make V=1" to debug this script @@ -214,10 +213,6 @@ if [ "$1" = "clean" ]; then exit 0 fi -if is_enabled CONFIG_MODULES; then - ${MAKE} -f "${srctree}/scripts/Makefile.vmlinux" .vmlinux.export.o -fi - ${MAKE} -f "${srctree}/scripts/Makefile.build" obj=init init/version-timestamp.o btf_vmlinux_bin_o="" -- cgit