Le 05/08/2025 à 13:59, Venkat Rao Bagalkote a écrit :
On 05/08/25 1:04 pm, Christophe Leroy wrote:
Le 05/08/2025 à 08:27, Saket Kumar Bhaskar a écrit :
bpf_jit_emit_probe_mem_store() is introduced to emit instructions for
storing memory values depending on the size (byte, halfword,
word, doubleword).
Build break with this patch
CC arch/powerpc/net/bpf_jit_comp64.o
arch/powerpc/net/bpf_jit_comp64.c:395:12: error:
'bpf_jit_emit_probe_mem_store' defined but not used [-Werror=unused-
function]
static int bpf_jit_emit_probe_mem_store(struct codegen_context *ctx,
u32 src_reg, s16 off,
^~~~~~~~~~~~~~~~~~~~~~~~~~~~
cc1: all warnings being treated as errors
make[4]: *** [scripts/Makefile.build:287: arch/powerpc/net/
bpf_jit_comp64.o] Error 1
I tried this on top of bpf-next, and for me build passed.
Build of _this_ patch (alone) passed ?
This patch defines a static function but doesn't use it, so the build
must breaks because of that, unless you have set CONFIG_PPC_DISABLE_WERROR.
Following patch starts using this function so then the build doesn't
break anymore. But until next patch is applied the build doesn't work.
Both patches have to be squashed together in order to not break
bisectability of the kernel.
Christophe
Note: I applied https://eur01.safelinks.protection.outlook.com/?
url=https%3A%2F%2Flore.kernel.org%2Fbpf%2F20250717202935.29018-2-
puranjay%40kernel.org%2F&data=05%7C02%7Cchristophe.leroy%40csgroup.eu%7C0468473019834e07ef2b08ddd4179b9c%7C8b87af7d86474dc78df45f69a2011bb5%7C0%7C0%7C638899920058624267%7CUnknown%7CTWFpbGZsb3d8eyJFbXB0eU1hcGkiOnRydWUsIlYiOiIwLjAuMDAwMCIsIlAiOiJXaW4zMiIsIkFOIjoiTWFpbCIsIldUIjoyfQ%3D%3D%7C0%7C%7C%7C&sdata=iZLg9NUWxtH3vO1STI8wRYLzwvhohd2KKTAGYDe3WnM%3D&reserved=0 before applying current patch.
gcc version 14.2.1 20250110
uname -r: 6.16.0-gf2844c7fdb07
bpf-next repo: https://eur01.safelinks.protection.outlook.com/?
url=https%3A%2F%2Fkernel.googlesource.com%2Fpub%2Fscm%2Flinux%2Fkernel%2Fgit%2Fbpf%2Fbpf-next&data=05%7C02%7Cchristophe.leroy%40csgroup.eu%7C0468473019834e07ef2b08ddd4179b9c%7C8b87af7d86474dc78df45f69a2011bb5%7C0%7C0%7C638899920058644309%7CUnknown%7CTWFpbGZsb3d8eyJFbXB0eU1hcGkiOnRydWUsIlYiOiIwLjAuMDAwMCIsIlAiOiJXaW4zMiIsIkFOIjoiTWFpbCIsIldUIjoyfQ%3D%3D%7C0%7C%7C%7C&sdata=OrMauttrzPbaFYhzKdkH5l%2FltISc95MwitnUC7YLhJQ%3D&reserved=0
HEAD:
commit f3af62b6cee8af9f07012051874af2d2a451f0e5 (origin/master, origin/
HEAD)
Author: Tao Chen <chen.dyl...@linux.dev>
Date: Wed Jul 23 22:44:42 2025 +0800
bpftool: Add bash completion for token argument
Build Success logs:
TEST-OBJ [test_progs-cpuv4] xdp_vlan.test.o
TEST-OBJ [test_progs-cpuv4] xdpwall.test.o
TEST-OBJ [test_progs-cpuv4] xfrm_info.test.o
BINARY bench
BINARY test_maps
BINARY test_progs
BINARY test_progs-no_alu32
BINARY test_progs-cpuv4
Regards,
Venkat.
Signed-off-by: Saket Kumar Bhaskar <sk...@linux.ibm.com>
---
arch/powerpc/net/bpf_jit_comp64.c | 30 ++++++++++++++++++++++++++++++
1 file changed, 30 insertions(+)
diff --git a/arch/powerpc/net/bpf_jit_comp64.c b/arch/powerpc/net/
bpf_jit_comp64.c
index 025524378443..489de21fe3d6 100644
--- a/arch/powerpc/net/bpf_jit_comp64.c
+++ b/arch/powerpc/net/bpf_jit_comp64.c
@@ -409,6 +409,36 @@ asm (
" blr ;"
);
+static int bpf_jit_emit_probe_mem_store(struct codegen_context
*ctx, u32 src_reg, s16 off,
+ u32 code, u32 *image)
+{
+ u32 tmp1_reg = bpf_to_ppc(TMP_REG_1);
+ u32 tmp2_reg = bpf_to_ppc(TMP_REG_2);
+
+ switch (BPF_SIZE(code)) {
+ case BPF_B:
+ EMIT(PPC_RAW_STB(src_reg, tmp1_reg, off));
+ break;
+ case BPF_H:
+ EMIT(PPC_RAW_STH(src_reg, tmp1_reg, off));
+ break;
+ case BPF_W:
+ EMIT(PPC_RAW_STW(src_reg, tmp1_reg, off));
+ break;
+ case BPF_DW:
+ if (off % 4) {
+ EMIT(PPC_RAW_LI(tmp2_reg, off));
+ EMIT(PPC_RAW_STDX(src_reg, tmp1_reg, tmp2_reg));
+ } else {
+ EMIT(PPC_RAW_STD(src_reg, tmp1_reg, off));
+ }
+ break;
+ default:
+ return -EINVAL;
+ }
+ return 0;
+}
+
static int emit_atomic_ld_st(const struct bpf_insn insn, struct
codegen_context *ctx, u32 *image)
{
u32 code = insn.code;
