diff options
| author | Alan Maguire <alan.maguire@oracle.com> | 2024-06-20 10:17:32 +0100 |
|---|---|---|
| committer | Andrii Nakryiko <andrii@kernel.org> | 2024-06-21 14:45:07 -0700 |
| commit | 46fb0b62ea29c0dbcb3e44f1d67aafe79bc6e045 (patch) | |
| tree | ee099472310e53d874ad531b3747d3ea760a1293 /scripts | |
| parent | 8646db238997df36c6ad71a9d7e0b52ceee221b2 (diff) | |
kbuild,bpf: Add module-specific pahole flags for distilled base BTF
Support creation of module BTF along with distilled base BTF;
the latter is stored in a .BTF.base ELF section and supplements
split BTF references to base BTF with information about base types,
allowing for later relocation of split BTF with a (possibly
changed) base. resolve_btfids detects the presence of a .BTF.base
section and will use it instead of the base BTF it is passed in
BTF id resolution.
Modules will be built with a distilled .BTF.base section for external
module build, i.e.
make -C. -M=path2/module
...while in-tree module build as part of a normal kernel build will
not generate distilled base BTF; this is because in-tree modules
change with the kernel and do not require BTF relocation for the
running vmlinux.
Signed-off-by: Alan Maguire <alan.maguire@oracle.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Reviewed-by: Eduard Zingerman <eddyz87@gmail.com>
Link: https://lore.kernel.org/bpf/20240620091733.1967885-6-alan.maguire@oracle.com
Diffstat (limited to 'scripts')
| -rw-r--r-- | scripts/Makefile.btf | 5 | ||||
| -rw-r--r-- | scripts/Makefile.modfinal | 2 |
2 files changed, 6 insertions, 1 deletions
diff --git a/scripts/Makefile.btf b/scripts/Makefile.btf index 2597e3d4d6e0..b75f09f3f424 100644 --- a/scripts/Makefile.btf +++ b/scripts/Makefile.btf @@ -21,8 +21,13 @@ else # Switch to using --btf_features for v1.26 and later. pahole-flags-$(call test-ge, $(pahole-ver), 126) = -j --btf_features=encode_force,var,float,enum64,decl_tag,type_tag,optimized_func,consistent_func,decl_tag_kfuncs +ifneq ($(KBUILD_EXTMOD),) +module-pahole-flags-$(call test-ge, $(pahole-ver), 126) += --btf_features=distilled_base +endif + endif pahole-flags-$(CONFIG_PAHOLE_HAS_LANG_EXCLUDE) += --lang_exclude=rust export PAHOLE_FLAGS := $(pahole-flags-y) +export MODULE_PAHOLE_FLAGS := $(module-pahole-flags-y) diff --git a/scripts/Makefile.modfinal b/scripts/Makefile.modfinal index 3bec9043e4f3..1fa98b5e952b 100644 --- a/scripts/Makefile.modfinal +++ b/scripts/Makefile.modfinal @@ -41,7 +41,7 @@ quiet_cmd_btf_ko = BTF [M] $@ if [ ! -f vmlinux ]; then \ printf "Skipping BTF generation for %s due to unavailability of vmlinux\n" $@ 1>&2; \ else \ - LLVM_OBJCOPY="$(OBJCOPY)" $(PAHOLE) -J $(PAHOLE_FLAGS) --btf_base vmlinux $@; \ + LLVM_OBJCOPY="$(OBJCOPY)" $(PAHOLE) -J $(PAHOLE_FLAGS) $(MODULE_PAHOLE_FLAGS) --btf_base vmlinux $@; \ $(RESOLVE_BTFIDS) -b vmlinux $@; \ fi; |