[PATCH powerpc/next 05/17] powerpc64/bpf: Use r12 for constant blinding
From: Naveen N. Rao <hidden>
Date: 2022-02-14 11:13:45
Also in:
bpf
Subsystem:
bpf jit for powerpc (32-bit and 64-bit), bpf [general] (safe dynamic programs and tools), linux for powerpc (32-bit and 64-bit), the rest · Maintainers:
Hari Bathini, Christophe Leroy, Alexei Starovoitov, Daniel Borkmann, Andrii Nakryiko, Eduard Zingerman, Kumar Kartikeya Dwivedi, Madhavan Srinivasan, Linus Torvalds
In preparation for preserving kernel toc in r2, switch BPF_REG_AX from r2 to r12. r12 is not used by bpf JIT except during external helper/bpf calls, or with BPF_NOSPEC. These sequences aren't emitted when BPF_REG_AX is used for constant blinding and other purposes. Signed-off-by: Naveen N. Rao <redacted> --- arch/powerpc/net/bpf_jit64.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/arch/powerpc/net/bpf_jit64.h b/arch/powerpc/net/bpf_jit64.h
index b63b35e45e558c..82cdfee412784a 100644
--- a/arch/powerpc/net/bpf_jit64.h
+++ b/arch/powerpc/net/bpf_jit64.h@@ -56,7 +56,7 @@ const int b2p[MAX_BPF_JIT_REG + 2] = { /* frame pointer aka BPF_REG_10 */ [BPF_REG_FP] = 31, /* eBPF jit internal registers */ - [BPF_REG_AX] = 2, + [BPF_REG_AX] = 12, [TMP_REG_1] = 9, [TMP_REG_2] = 10 };
--
2.35.1