| Message ID | 20211231151018.3781550-1-houtao1@huawei.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | bpf, arm64: use emit_addr_mov_i64() for BPF_PSEUDO_FUNC | expand |
Hello: This patch was applied to bpf/bpf-next.git (master) by Daniel Borkmann <daniel@iogearbox.net>: On Fri, 31 Dec 2021 23:10:18 +0800 you wrote: > The following error is reported when running "./test_progs -t for_each" > under arm64: > > bpf_jit: multi-func JIT bug 58 != 56 > ...... > JIT doesn't support bpf-to-bpf calls > > [...] Here is the summary with links: - bpf, arm64: use emit_addr_mov_i64() for BPF_PSEUDO_FUNC https://git.kernel.org/bpf/bpf-next/c/e4a41c2c1fa9 You are awesome, thank you!
diff --git a/arch/arm64/net/bpf_jit_comp.c b/arch/arm64/net/bpf_jit_comp.c index f81e71f6e8bf..acfc3d4d712c 100644 --- a/arch/arm64/net/bpf_jit_comp.c +++ b/arch/arm64/net/bpf_jit_comp.c @@ -792,7 +792,10 @@ static int build_insn(const struct bpf_insn *insn, struct jit_ctx *ctx, u64 imm64; imm64 = (u64)insn1.imm << 32 | (u32)imm; - emit_a64_mov_i64(dst, imm64, ctx); + if (bpf_pseudo_func(insn)) + emit_addr_mov_i64(dst, imm64, ctx); + else + emit_a64_mov_i64(dst, imm64, ctx); return 1; }
The following error is reported when running "./test_progs -t for_each" under arm64: bpf_jit: multi-func JIT bug 58 != 56 ...... JIT doesn't support bpf-to-bpf calls The root cause is the size of BPF_PSEUDO_FUNC instruction increases from 2 to 3 after the address of called bpf-function is settled and there are two bpf-to-bpf calls in test_pkt_access. The generated instructions are shown below: >before callback_fn is jited, its addr is 0x1-00000001 0x48: 21 00 C0 D2 movz x1, #0x1, lsl #32 0x4c: 21 00 80 F2 movk x1, #0x1 >after callback_fn is jited, its addr is 0xfffffe0017f2fb84 0x48: E1 3F C0 92 movn x1, #0x1ff, lsl #32 0x4c: 41 FE A2 F2 movk x1, #0x17f2, lsl #16 0x50: 81 70 9F F2 movk x1, #0xfb84 Fixing it by using emit_addr_mov_i64() for BPF_PSEUDO_FUNC, so the size of jited image will not change. Fixes: 69c087ba6225 ("bpf: Add bpf_for_each_map_elem() helper") Signed-off-by: Hou Tao <houtao1@huawei.com> --- arch/arm64/net/bpf_jit_comp.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-)