From 4759670bc3e670069c055c2b33174813099fea4f Mon Sep 17 00:00:00 2001 From: Josh Poimboeuf Date: Mon, 24 Mar 2025 14:55:55 -0700 Subject: objtool: Fix CONFIG_OBJTOOL_WERROR for vmlinux.o With (!X86_KERNEL_IBT && !LTO_CLANG && NOINSTR_VALIDATION), objtool runs on both translation units and vmlinux.o. With CONFIG_OBJTOOL_WERROR, the TUs get --Werror but vmlinux.o doesn't. Fix that. Signed-off-by: Josh Poimboeuf Signed-off-by: Ingo Molnar Cc: Linus Torvalds Link: https://lore.kernel.org/r/4f71ab9b947ffc47b6a87dd3b9aff4bb32b36d0a.1742852846.git.jpoimboe@kernel.org --- scripts/Makefile.vmlinux_o | 14 +++++++++++--- 1 file changed, 11 insertions(+), 3 deletions(-) (limited to 'scripts') diff --git a/scripts/Makefile.vmlinux_o b/scripts/Makefile.vmlinux_o index 0b6e2ebf60dc..f476f5605029 100644 --- a/scripts/Makefile.vmlinux_o +++ b/scripts/Makefile.vmlinux_o @@ -30,12 +30,20 @@ endif # objtool for vmlinux.o # --------------------------------------------------------------------------- # -# For LTO and IBT, objtool doesn't run on individual translation units. -# Run everything on vmlinux instead. +# For delay-objtool (IBT or LTO), objtool doesn't run on individual translation +# units. Instead it runs on vmlinux.o. +# +# For !delay-objtool + CONFIG_NOINSTR_VALIDATION, it runs on both translation +# units and vmlinux.o, with the latter only used for noinstr/unret validation. objtool-enabled := $(or $(delay-objtool),$(CONFIG_NOINSTR_VALIDATION)) -vmlinux-objtool-args-$(delay-objtool) += $(objtool-args-y) +ifeq ($(delay-objtool),y) +vmlinux-objtool-args-y += $(objtool-args-y) +else +vmlinux-objtool-args-$(CONFIG_OBJTOOL_WERROR) += --Werror +endif + vmlinux-objtool-args-$(CONFIG_GCOV_KERNEL) += --no-unreachable vmlinux-objtool-args-$(CONFIG_NOINSTR_VALIDATION) += --noinstr \ $(if $(or $(CONFIG_MITIGATION_UNRET_ENTRY),$(CONFIG_MITIGATION_SRSO)), --unret) -- cgit v1.2.3 From d39f82a058c0269392a797cb04f2a6064e5dcab6 Mon Sep 17 00:00:00 2001 From: Josh Poimboeuf Date: Mon, 24 Mar 2025 14:56:00 -0700 Subject: objtool: Reduce CONFIG_OBJTOOL_WERROR verbosity Remove the following from CONFIG_OBJTOOL_WERROR: * backtrace * "upgraded warnings to errors" message * cmdline args This makes the default output less cluttered and makes it easier to spot the actual warnings. Note the above options are still are available with --verbose or OBJTOOL_VERBOSE=1. Also, do the cmdline arg printing on all warnings, regardless of werror. Signed-off-by: Josh Poimboeuf Signed-off-by: Ingo Molnar Cc: Linus Torvalds Link: https://lore.kernel.org/r/d61df69f64b396fa6b2a1335588aad7a34ea9e71.1742852846.git.jpoimboe@kernel.org --- scripts/Makefile.lib | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'scripts') diff --git a/scripts/Makefile.lib b/scripts/Makefile.lib index 57620b439a1f..b93597420daf 100644 --- a/scripts/Makefile.lib +++ b/scripts/Makefile.lib @@ -277,7 +277,7 @@ objtool-args-$(CONFIG_HAVE_STATIC_CALL_INLINE) += --static-call objtool-args-$(CONFIG_HAVE_UACCESS_VALIDATION) += --uaccess objtool-args-$(CONFIG_GCOV_KERNEL) += --no-unreachable objtool-args-$(CONFIG_PREFIX_SYMBOLS) += --prefix=$(CONFIG_FUNCTION_PADDING_BYTES) -objtool-args-$(CONFIG_OBJTOOL_WERROR) += --Werror --backtrace +objtool-args-$(CONFIG_OBJTOOL_WERROR) += --Werror objtool-args = $(objtool-args-y) \ $(if $(delay-objtool), --link) \ -- cgit v1.2.3 From 876a4bce3849b235d752d13ec3180e15a35e52de Mon Sep 17 00:00:00 2001 From: Josh Poimboeuf Date: Mon, 24 Mar 2025 14:56:02 -0700 Subject: objtool: Remove --no-unreachable for noinstr-only vmlinux.o runs For (!X86_KERNEL_IBT && !LTO_CLANG && NOINSTR_VALIDATION), objtool runs on both translation units and vmlinux.o. The vmlinux.o run only does noinstr/noret validation. In that case --no-unreachable has no effect. Remove it. Note that for ((X86_KERNEL_IBT || LTO_CLANG) && KCOV), --no-unreachable still gets set in objtool-args-y by scripts/Makefile.lib. Signed-off-by: Josh Poimboeuf Signed-off-by: Ingo Molnar Cc: Linus Torvalds Link: https://lore.kernel.org/r/05414246a0124db2f21b0d071b652aa9043d039d.1742852847.git.jpoimboe@kernel.org --- scripts/Makefile.vmlinux_o | 1 - 1 file changed, 1 deletion(-) (limited to 'scripts') diff --git a/scripts/Makefile.vmlinux_o b/scripts/Makefile.vmlinux_o index f476f5605029..938c7457717e 100644 --- a/scripts/Makefile.vmlinux_o +++ b/scripts/Makefile.vmlinux_o @@ -44,7 +44,6 @@ else vmlinux-objtool-args-$(CONFIG_OBJTOOL_WERROR) += --Werror endif -vmlinux-objtool-args-$(CONFIG_GCOV_KERNEL) += --no-unreachable vmlinux-objtool-args-$(CONFIG_NOINSTR_VALIDATION) += --noinstr \ $(if $(or $(CONFIG_MITIGATION_UNRET_ENTRY),$(CONFIG_MITIGATION_SRSO)), --unret) -- cgit v1.2.3 From 55c78035a1a8dfb05f1472018ce2a651701adb7d Mon Sep 17 00:00:00 2001 From: Josh Poimboeuf Date: Mon, 31 Mar 2025 21:26:36 -0700 Subject: objtool: Silence more KCOV warnings, part 2 Similar to GCOV, KCOV can leave behind dead code and undefined behavior. Warnings related to those should be ignored. The previous commit: 6b023c784204 ("objtool: Silence more KCOV warnings") ... only did so for CONFIG_CGOV_KERNEL. Also do it for CONFIG_KCOV, but for real this time. Fixes the following warning: vmlinux.o: warning: objtool: synaptics_report_mt_data: unexpected end of section .text.synaptics_report_mt_data Fixes: 6b023c784204 ("objtool: Silence more KCOV warnings") Reported-by: kernel test robot Signed-off-by: Josh Poimboeuf Signed-off-by: Ingo Molnar Cc: Linus Torvalds Link: https://lore.kernel.org/r/a44ba16e194bcbc52c1cef3d3cd9051a62622723.1743481539.git.jpoimboe@kernel.org Closes: https://lore.kernel.org/oe-kbuild-all/202503282236.UhfRsF3B-lkp@intel.com/ --- scripts/Makefile.lib | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'scripts') diff --git a/scripts/Makefile.lib b/scripts/Makefile.lib index b93597420daf..4d543054f723 100644 --- a/scripts/Makefile.lib +++ b/scripts/Makefile.lib @@ -275,7 +275,7 @@ objtool-args-$(CONFIG_MITIGATION_SLS) += --sls objtool-args-$(CONFIG_STACK_VALIDATION) += --stackval objtool-args-$(CONFIG_HAVE_STATIC_CALL_INLINE) += --static-call objtool-args-$(CONFIG_HAVE_UACCESS_VALIDATION) += --uaccess -objtool-args-$(CONFIG_GCOV_KERNEL) += --no-unreachable +objtool-args-$(or $(CONFIG_GCOV_KERNEL),$(CONFIG_KCOV)) += --no-unreachable objtool-args-$(CONFIG_PREFIX_SYMBOLS) += --prefix=$(CONFIG_FUNCTION_PADDING_BYTES) objtool-args-$(CONFIG_OBJTOOL_WERROR) += --Werror -- cgit v1.2.3