On 2025/8/19 下午7:19, Huacai Chen wrote:
In __arch_prepare_bpf_trampoline(), retval_off is meaningful only when save_ret is not 0, so the current logic is correct. But it may cause a build warning: arch/loongarch/net/bpf_jit.c:1547 __arch_prepare_bpf_trampoline() error: uninitialized symbol 'retval_off'. So initialize retval_off unconditionally to fix it. Fixes: f9b6b41f0cf3 ("LoongArch: BPF: Add basic bpf trampoline support") Closes: https://lore.kernel.org/r/202508191020.PBBh07cK-lkp@xxxxxxxxx/ Reported-by: kernel test robot <lkp@xxxxxxxxx> Reported-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx> Signed-off-by: Huacai Chen <chenhuacai@xxxxxxxxxxx> --- arch/loongarch/net/bpf_jit.c | 9 ++++----- 1 file changed, 4 insertions(+), 5 deletions(-) diff --git a/arch/loongarch/net/bpf_jit.c b/arch/loongarch/net/bpf_jit.c index abfdb6bb5c38..a73f6ea4ed4a 100644 --- a/arch/loongarch/net/bpf_jit.c +++ b/arch/loongarch/net/bpf_jit.c @@ -1504,11 +1504,10 @@ static int __arch_prepare_bpf_trampoline(struct jit_ctx *ctx, struct bpf_tramp_i stack_size += 16;save_ret = flags & (BPF_TRAMP_F_CALL_ORIG | BPF_TRAMP_F_RET_FENTRY_RET);- if (save_ret) { - /* Save BPF R0 and A0 */ - stack_size += 16; - retval_off = stack_size; - } + if (save_ret) + stack_size += 16; /* Save BPF R0 and A0 */ + + retval_off = stack_size;
Just init retval_off as 0 at the beginning of this function? What is the difference? which is better? Thanks, Tiezhu
