On 1/20/25 3:30 AM, Jinghao Jia wrote:
Commit 13b25489b6f8 ("kbuild: change working directory to external
module directory with M=") changed kbuild working directory of bpf
samples to $(srctree)/samples/bpf, which broke the vmlinux path for
VMLINUX_BTF, as the Makefile assumes the current work directory to be
$(srctree):
Makefile:316: *** Cannot find a vmlinux for VMLINUX_BTF at any of " /path/to/linux/samples/bpf/vmlinux", build the kernel or set VMLINUX_BTF like "VMLINUX_BTF=/sys/kernel/btf/vmlinux" or VMLINUX_H variable. Stop.
Correctly refer to the kernel source directory using $(srctree).
Fixes: 13b25489b6f8 ("kbuild: change working directory to external module directory with M=")
Tested-by: Ruowen Qin <ruqin@xxxxxxxxxx>
Signed-off-by: Jinghao Jia <jinghao7@xxxxxxxxxxxx>
---
samples/bpf/Makefile | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/samples/bpf/Makefile b/samples/bpf/Makefile
index 96a05e70ace3..f97295724a14 100644
--- a/samples/bpf/Makefile
+++ b/samples/bpf/Makefile
@@ -307,7 +307,7 @@ $(obj)/$(TRACE_HELPERS): TPROGS_CFLAGS := $(TPROGS_CFLAGS) -D__must_check=
VMLINUX_BTF_PATHS ?= $(abspath $(if $(O),$(O)/vmlinux)) \
$(abspath $(if $(KBUILD_OUTPUT),$(KBUILD_OUTPUT)/vmlinux)) \
- $(abspath ./vmlinux)
+ $(abspath $(srctree)/vmlinux)
VMLINUX_BTF ?= $(abspath $(firstword $(wildcard $(VMLINUX_BTF_PATHS))))
$(obj)/vmlinux.h: $(VMLINUX_BTF) $(BPFTOOL)
samples/hid/Makefile needs this fix as well :
VMLINUX_BTF_PATHS ?= $(abspath $(if $(O),$(O)/vmlinux)) \
$(abspath $(if $(KBUILD_OUTPUT),$(KBUILD_OUTPUT)/vmlinux)) \
$(abspath ./vmlinux)
VMLINUX_BTF ?= $(abspath $(firstword $(wildcard $(VMLINUX_BTF_PATHS))))
