Commit 4eece7e6 authored by Tiezhu Yang's avatar Tiezhu Yang Committed by Huacai Chen

LoongArch: BPF: Fix check condition to call lu32id in move_imm()

As the code comment says, the initial aim is to reduce one instruction
in some corner cases, if bit[51:31] is all 0 or all 1, no need to call
lu32id. That is to say, it should call lu32id only if bit[51:31] is not
all 0 and not all 1. The current code always call lu32id, the result is
right but the logic is unexpected and wrong, fix it.

Cc: stable@vger.kernel.org # 6.1
Fixes: 5dc61552 ("LoongArch: Add BPF JIT support")
Reported-by: default avatarColin King (gmail) <colin.i.king@gmail.com>
Closes: https://lore.kernel.org/all/bcf97046-e336-712a-ac68-7fd194f2953e@gmail.com/Signed-off-by: default avatarTiezhu Yang <yangtiezhu@loongson.cn>
Signed-off-by: default avatarHuacai Chen <chenhuacai@loongson.cn>
parent de0e30be
......@@ -150,7 +150,7 @@ static inline void move_imm(struct jit_ctx *ctx, enum loongarch_gpr rd, long imm
* no need to call lu32id to do a new filled operation.
*/
imm_51_31 = (imm >> 31) & 0x1fffff;
if (imm_51_31 != 0 || imm_51_31 != 0x1fffff) {
if (imm_51_31 != 0 && imm_51_31 != 0x1fffff) {
/* lu32id rd, imm_51_32 */
imm_51_32 = (imm >> 32) & 0xfffff;
emit_insn(ctx, lu32id, rd, imm_51_32);
......
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