[PATCH v3 1/4] powerpc/bpf: Add support for instruction array

adubey
2026-04-01T11:21:34Z

On loading the BPF program, the verifier might adjust/omit some
instructions. The adjusted instruction offset is accounted in the
map containing original instruction -> xlated mapping. This patch
add ppc64 JIT support to additionally build the xlated->jitted
mapping for every instruction present in instruction array. This
change is needed to enable support for indirect jumps, added in a
subsequent patch.

Invoke bpf_prog_update_insn_ptrs() with offset pair of xlated_offset
and jited_offset. The offset mapping is already available, which is
being used for bpf_prog_fill_jited_linfo() and can be directly used
for bpf_prog_update_insn_ptrs() as well.

Additional details present at:

commit b4ce5923e780 ("bpf, x86: add new map type: instructions array")

Signed-off-by: Abhishek Dubey <adubey@linux.ibm.com>
Acked-by: Hari Bathini <hbathini@linux.ibm.com>
---
arch/powerpc/net/bpf_jit_comp.c | 7 +++++++
1 file changed, 7 insertions(+)

diff --git a/arch/powerpc/net/bpf_jit_comp.c b/arch/powerpc/net/bpf_jit_comp.c
index b2fdf8ff9c60..50103b3794fb 100644
--- a/arch/powerpc/net/bpf_jit_comp.c
+++ b/arch/powerpc/net/bpf_jit_comp.c
@@ -373,6 +373,13 @@ struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *fp)
goto out_addrs;
}
bpf_prog_fill_jited_linfo(fp, addrs);
+ /*
+ * On ABI V1, executable code starts after the function
+ * descriptor, so adjust base accordingly.
+ */
+ bpf_prog_update_insn_ptrs(fp, addrs,
+ (void *)fimage + FUNCTION_DESCR_SIZE);
+
out_addrs:
if (!image && priv_stack_ptr) {
fp->aux->priv_stack_ptr = NULL;
--
2.52.0