| Message ID | 20201121070829.2612884-1-andrii@kernel.org (mailing list archive) |
|---|---|
| State | Accepted |
| Commit | e732b538f4557cd0a856bbce3cde55d2dfef3b03 |
| Delegated to: | BPF |
| Headers | show |
| Series | [RESEND,bpf-next,1/2] kbuild: skip module BTF generation for out-of-tree external modules | expand |
| Context | Check | Description |
|---|---|---|
| netdev/cover_letter | success | Link |
| netdev/fixes_present | success | Link |
| netdev/patch_count | success | Link |
| netdev/tree_selection | success | Clearly marked for bpf-next |
| netdev/subject_prefix | success | Link |
| netdev/source_inline | success | Was 0 now: 0 |
| netdev/verify_signedoff | success | Link |
| netdev/module_param | success | Was 0 now: 0 |
| netdev/build_32bit | success | Errors and warnings before: 0 this patch: 0 |
| netdev/kdoc | success | Errors and warnings before: 0 this patch: 0 |
| netdev/verify_fixes | success | Link |
| netdev/checkpatch | success | total: 0 errors, 0 warnings, 0 checks, 21 lines checked |
| netdev/build_allmodconfig_warn | success | Errors and warnings before: 0 this patch: 0 |
| netdev/header_inline | success | Link |
| netdev/stable | success | Stable not CCed |
Hello: This series was applied to bpf/bpf-next.git (refs/heads/master): On Fri, 20 Nov 2020 23:08:28 -0800 you wrote: > In some modes of operation, Kbuild allows to build modules without having > vmlinux image around. In such case, generation of module BTF is impossible. > This patch changes the behavior to emit a warning about impossibility of > generating kernel module BTF, instead of breaking the build. This is especially > important for out-of-tree external module builds. > > In vmlinux-less mode: > > [...] Here is the summary with links: - [RESEND,bpf-next,1/2] kbuild: skip module BTF generation for out-of-tree external modules https://git.kernel.org/bpf/bpf-next/c/e732b538f455 - [RESEND,bpf-next,2/2] bpf: sanitize BTF data pointer after module is loaded https://git.kernel.org/bpf/bpf-next/c/607c543f939d You are awesome, thank you! -- Deet-doot-dot, I am a bot. https://korg.docs.kernel.org/patchwork/pwbot.html
diff --git a/scripts/Makefile.modfinal b/scripts/Makefile.modfinal index 02b892421f7a..d49ec001825d 100644 --- a/scripts/Makefile.modfinal +++ b/scripts/Makefile.modfinal @@ -38,7 +38,12 @@ quiet_cmd_ld_ko_o = LD [M] $@ $(if $(ARCH_POSTLINK), $(MAKE) -f $(ARCH_POSTLINK) $@, true) quiet_cmd_btf_ko = BTF [M] $@ - cmd_btf_ko = LLVM_OBJCOPY=$(OBJCOPY) $(PAHOLE) -J --btf_base vmlinux $@ + cmd_btf_ko = \ + if [ -f vmlinux ]; then \ + LLVM_OBJCOPY=$(OBJCOPY) $(PAHOLE) -J --btf_base vmlinux $@; \ + else \ + printf "Skipping BTF generation for %s due to unavailability of vmlinux\n" $@ 1>&2; \ + fi; # Same as newer-prereqs, but allows to exclude specified extra dependencies newer_prereqs_except = $(filter-out $(PHONY) $(1),$?) @@ -49,7 +54,7 @@ if_changed_except = $(if $(call newer_prereqs_except,$(2))$(cmd-check), \ printf '%s\n' 'cmd_$@ := $(make-cmd)' > $(dot-target).cmd, @:) # Re-generate module BTFs if either module's .ko or vmlinux changed -$(modules): %.ko: %.o %.mod.o scripts/module.lds vmlinux FORCE +$(modules): %.ko: %.o %.mod.o scripts/module.lds $(if $(KBUILD_BUILTIN),vmlinux) FORCE +$(call if_changed_except,ld_ko_o,vmlinux) ifdef CONFIG_DEBUG_INFO_BTF_MODULES +$(if $(newer-prereqs),$(call cmd,btf_ko))
In some modes of operation, Kbuild allows to build modules without having vmlinux image around. In such case, generation of module BTF is impossible. This patch changes the behavior to emit a warning about impossibility of generating kernel module BTF, instead of breaking the build. This is especially important for out-of-tree external module builds. In vmlinux-less mode: $ make clean $ make modules_prepare $ touch drivers/acpi/button.c $ make M=drivers/acpi ... CC [M] drivers/acpi/button.o MODPOST drivers/acpi/Module.symvers LD [M] drivers/acpi/button.ko BTF [M] drivers/acpi/button.ko Skipping BTF generation for drivers/acpi/button.ko due to unavailability of vmlinux ... $ readelf -S ~/linux-build/default/drivers/acpi/button.ko | grep BTF -A1 ... empty ... Now with normal build: $ make all ... LD [M] drivers/acpi/button.ko BTF [M] drivers/acpi/button.ko ... $ readelf -S ~/linux-build/default/drivers/acpi/button.ko | grep BTF -A1 [60] .BTF PROGBITS 0000000000000000 00029310 000000000000ab3f 0000000000000000 0 0 1 Reported-by: Bruce Allan <bruce.w.allan@intel.com> Fixes: 5f9ae91f7c0d ("kbuild: Build kernel module BTFs if BTF is enabled and pahole supports it") Cc: Jessica Yu <jeyu@kernel.org> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Masahiro Yamada <yamada.masahiro@socionext.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> --- scripts/Makefile.modfinal | 9 +++++++-- 1 file changed, 7 insertions(+), 2 deletions(-)