[PATCH 6.6] Revert "LoongArch: BPF: Sign extend kfunc call arguments"

["Wentao Guan" <guanwentao@uniontech.com>]

It cause loongarch build failed. it need merge more depends,
such as "LoongArch: Add more instruction opcodes and emit_* helpers"
This reverts commit fd43edf357a3a1f5ed1c4bf450b60001c9091c39.

config: https://gist.github.com/opsiff/b6c9c32ade5f6d4abb5454a476f4c4e1
Signed-off-by: Wentao Guan <guanwentao@uniontech.com>
---
 arch/loongarch/net/bpf_jit.c | 16 ----------------
 arch/loongarch/net/bpf_jit.h | 26 --------------------------
 2 files changed, 42 deletions(-)

diff --git a/arch/loongarch/net/bpf_jit.c b/arch/loongarch/net/bpf_jit.c
index 54661cffd654f..c6400d7b95ee8 100644
--- a/arch/loongarch/net/bpf_jit.c
+++ b/arch/loongarch/net/bpf_jit.c
@@ -834,22 +834,6 @@ static int build_insn(const struct bpf_insn *insn, struct jit_ctx *ctx, bool ext
 		if (ret < 0)
 			return ret;
 
-		if (insn->src_reg == BPF_PSEUDO_KFUNC_CALL) {
-			const struct btf_func_model *m;
-			int i;
-
-			m = bpf_jit_find_kfunc_model(ctx->prog, insn);
-			if (!m)
-				return -EINVAL;
-
-			for (i = 0; i < m->nr_args; i++) {
-				u8 reg = regmap[BPF_REG_1 + i];
-				bool sign = m->arg_flags[i] & BTF_FMODEL_SIGNED_ARG;
-
-				emit_abi_ext(ctx, reg, m->arg_size[i], sign);
-			}
-		}
-
 		move_addr(ctx, t1, func_addr);
 		emit_insn(ctx, jirl, LOONGARCH_GPR_RA, t1, 0);
 
diff --git a/arch/loongarch/net/bpf_jit.h b/arch/loongarch/net/bpf_jit.h
index 9352ea5545308..f9c569f539491 100644
--- a/arch/loongarch/net/bpf_jit.h
+++ b/arch/loongarch/net/bpf_jit.h
@@ -87,32 +87,6 @@ static inline void emit_sext_32(struct jit_ctx *ctx, enum loongarch_gpr reg, boo
 	emit_insn(ctx, addiw, reg, reg, 0);
 }
 
-/* Emit proper extension according to ABI requirements.
- * Note that it requires a value of size `size` already resides in register `reg`.
- */
-static inline void emit_abi_ext(struct jit_ctx *ctx, int reg, u8 size, bool sign)
-{
-	/* ABI requires unsigned char/short to be zero-extended */
-	if (!sign && (size == 1 || size == 2))
-		return;
-
-	switch (size) {
-	case 1:
-		emit_insn(ctx, extwb, reg, reg);
-		break;
-	case 2:
-		emit_insn(ctx, extwh, reg, reg);
-		break;
-	case 4:
-		emit_insn(ctx, addiw, reg, reg, 0);
-		break;
-	case 8:
-		break;
-	default:
-		pr_warn("bpf_jit: invalid size %d for extension\n", size);
-	}
-}
-
 static inline void move_addr(struct jit_ctx *ctx, enum loongarch_gpr rd, u64 addr)
 {
 	u64 imm_11_0, imm_31_12, imm_51_32, imm_63_52;