diff options
| author | Andrii Nakryiko | 2020-12-10 17:59:46 -0800 |
|---|---|---|
| committer | Alexei Starovoitov | 2020-12-10 21:16:29 -0800 |
| commit | a67079b03165a17f9aceab3dd26b1638af68e0fc (patch) | |
| tree | 50eb1603f3a50f0849bff7cec78e12fb9c38f8bb /tools | |
| parent | 092fde0f863b72b67c4d6dc03844f5658fc00a35 (diff) | |
selftests/bpf: fix bpf_testmod.ko recompilation logic
bpf_testmod.ko build rule declared dependency on VMLINUX_BTF, but the variable
itself was initialized after the rule was declared, which often caused
bpf_testmod.ko to not be re-compiled. Fix by moving VMLINUX_BTF determination
sooner.
Also enforce bpf_testmod.ko recompilation when we detect that vmlinux image
changed by removing bpf_testmod/bpf_testmod.ko. This is necessary to generate
correct module's split BTF. Without it, Kbuild's module build logic might
determine that nothing changed on the kernel side and thus bpf_testmod.ko
shouldn't be rebuilt, so won't re-generate module BTF, which often leads to
module's BTF with wrong string offsets against vmlinux BTF. Removing .ko file
forces Kbuild to re-build the module.
Reported-by: Alexei Starovoitov <ast@kernel.org>
Fixes: 9f7fa225894c ("selftests/bpf: Add bpf_testmod kernel module for testing")
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/r/20201211015946.4062098-1-andrii@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Diffstat (limited to 'tools')
| -rw-r--r-- | tools/testing/selftests/bpf/Makefile | 15 |
1 files changed, 8 insertions, 7 deletions
diff --git a/tools/testing/selftests/bpf/Makefile b/tools/testing/selftests/bpf/Makefile index 50b3495d7ddf..8b515a17f44b 100644 --- a/tools/testing/selftests/bpf/Makefile +++ b/tools/testing/selftests/bpf/Makefile @@ -116,6 +116,13 @@ INCLUDE_DIR := $(SCRATCH_DIR)/include BPFOBJ := $(BUILD_DIR)/libbpf/libbpf.a RESOLVE_BTFIDS := $(BUILD_DIR)/resolve_btfids/resolve_btfids +VMLINUX_BTF_PATHS ?= $(if $(O),$(O)/vmlinux) \ + $(if $(KBUILD_OUTPUT),$(KBUILD_OUTPUT)/vmlinux) \ + ../../../../vmlinux \ + /sys/kernel/btf/vmlinux \ + /boot/vmlinux-$(shell uname -r) +VMLINUX_BTF ?= $(abspath $(firstword $(wildcard $(VMLINUX_BTF_PATHS)))) + # Define simple and short `make test_progs`, `make test_sysctl`, etc targets # to build individual tests. # NOTE: Semicolon at the end is critical to override lib.mk's default static @@ -140,6 +147,7 @@ $(OUTPUT)/urandom_read: urandom_read.c $(OUTPUT)/bpf_testmod.ko: $(VMLINUX_BTF) $(wildcard bpf_testmod/Makefile bpf_testmod/*.[ch]) $(call msg,MOD,,$@) + $(Q)$(RM) bpf_testmod/bpf_testmod.ko # force re-compilation $(Q)$(MAKE) $(submake_extras) -C bpf_testmod $(Q)cp bpf_testmod/bpf_testmod.ko $@ @@ -147,13 +155,6 @@ $(OUTPUT)/test_stub.o: test_stub.c $(BPFOBJ) $(call msg,CC,,$@) $(Q)$(CC) -c $(CFLAGS) -o $@ $< -VMLINUX_BTF_PATHS ?= $(if $(O),$(O)/vmlinux) \ - $(if $(KBUILD_OUTPUT),$(KBUILD_OUTPUT)/vmlinux) \ - ../../../../vmlinux \ - /sys/kernel/btf/vmlinux \ - /boot/vmlinux-$(shell uname -r) -VMLINUX_BTF ?= $(abspath $(firstword $(wildcard $(VMLINUX_BTF_PATHS)))) - DEFAULT_BPFTOOL := $(SCRATCH_DIR)/sbin/bpftool $(OUTPUT)/runqslower: $(BPFOBJ) | $(DEFAULT_BPFTOOL) |