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ALU32 operations write a 32-bit result and leave the upper 32 bits of the BPF register zero. The LoongArch JIT sign-extends the result of signed ALU32 BPF_DIV and BPF_MOD (off=1), so a negative 32-bit quotient or remainder leaves bits 63:32 set in JITted code while the verifier and interpreter model those bits as zero. Keep sign-extension on the operands, which signed divide needs, and zero-extend the ALU32 result after the divide or modulo instruction, matching the unsigned ALU32 div/mod paths and every other ALU32 operation in this JIT. Fixes:2425c9e002("LoongArch: BPF: Support signed div instructions") Fixes:7b6b13d329("LoongArch: BPF: Support signed mod instructions") Assisted-by: Claude:claude-opus-4-8 Acked-by: Tiezhu Yang <yangtiezhu@loongson.cn> Tested-by: Tiezhu Yang <yangtiezhu@loongson.cn> Signed-off-by: Nicholas Dudar <main.kalliope@gmail.com> Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>