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LoongArch: BPF: Adjust the jump offset of tail calls

Call the next bpf prog and skip the first instruction of TCC
initialization.

A total of 7 instructions are skipped:
'move t0, ra' 1 inst
'move_imm + jirl' 5 inst
'addid REG_TCC, zero, 0' 1 inst

Relevant test cases: the tailcalls test item in selftests/bpf.

Cc: stable@vger.kernel.org
Fixes: 677e6123e3d2 ("LoongArch: BPF: Disable trampoline for kernel module function trace")
Signed-off-by: Chenghao Duan <duanchenghao@kylinos.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>

authored by

Chenghao Duan and committed by
Huacai Chen 61319d15 d314e1f4

+1 -1
+1 -1
arch/loongarch/net/bpf_jit.c
··· 239 239 * Call the next bpf prog and skip the first instruction 240 240 * of TCC initialization. 241 241 */ 242 - emit_insn(ctx, jirl, LOONGARCH_GPR_ZERO, LOONGARCH_GPR_T3, 6); 242 + emit_insn(ctx, jirl, LOONGARCH_GPR_ZERO, LOONGARCH_GPR_T3, 7); 243 243 } 244 244 } 245 245