Re: [PATCH bpf-next] selftests/bpf: Fix building error when using userspace pt_regs

From: Pu Lehui
Date: Thu Dec 16 2021 - 21:25:05 EST




On 2021/12/16 12:06, Andrii Nakryiko wrote:
On Tue, Dec 14, 2021 at 5:54 AM Pu Lehui <pulehui@xxxxxxxxxx> wrote:

When building bpf selftests on arm64, the following error will occur:

progs/loop2.c:20:7: error: incomplete definition of type 'struct
user_pt_regs'

Some archs, like arm64 and riscv, use userspace pt_regs in
bpf_tracing.h, which causes build failure when bpf prog use
macro in bpf_tracing.h. So let's use vmlinux.h directly.

We could probably also extend bpf_tracing.h to work with
kernel-defined pt_regs, just like we do for x86 (see __KERNEL__ and
__VMLINUX_H__ checks). It's more work, but will benefit other end
users, not just selftests.

It might change a lot. We can use header file directory generated by "make headers_install" to fix it.

--- a/tools/testing/selftests/bpf/Makefile
+++ b/tools/testing/selftests/bpf/Makefile
@@ -294,7 +294,8 @@ MENDIAN=$(if $(IS_LITTLE_ENDIAN),-mlittle-endian,-mbig-endian)
CLANG_SYS_INCLUDES = $(call get_sys_includes,$(CLANG))
BPF_CFLAGS = -g -D__TARGET_ARCH_$(SRCARCH) $(MENDIAN) \
-I$(INCLUDE_DIR) -I$(CURDIR) -I$(APIDIR) \
- -I$(abspath $(OUTPUT)/../usr/include)
+ -I$(abspath $(OUTPUT)/../usr/include) \
+ -I../../../../usr/include

Signed-off-by: Pu Lehui <pulehui@xxxxxxxxxx>
---
tools/testing/selftests/bpf/progs/loop1.c | 8 ++------
tools/testing/selftests/bpf/progs/loop2.c | 8 ++------
tools/testing/selftests/bpf/progs/loop3.c | 8 ++------
tools/testing/selftests/bpf/progs/loop6.c | 20 ++++++-------------
.../selftests/bpf/progs/test_overhead.c | 8 ++------
.../selftests/bpf/progs/test_probe_user.c | 6 +-----
6 files changed, 15 insertions(+), 43 deletions(-)


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