Re: [PATCH bpf-next v2 1/2] bpf, x64: Fix a jit convergence issue

[Yonghong Song <yonghong.song@linux.dev>]

On 9/4/24 9:56 AM, Alexei Starovoitov wrote:
> On Tue, Sep 3, 2024 at 4:00 PM Yonghong Song <yonghong.song@linux.dev> wrote:
>>
>> diff --git a/arch/x86/net/bpf_jit_comp.c b/arch/x86/net/bpf_jit_comp.c
>> index 074b41fafbe3..63c4816ed4e7 100644
>> --- a/arch/x86/net/bpf_jit_comp.c
>> +++ b/arch/x86/net/bpf_jit_comp.c
>> @@ -64,6 +64,57 @@ static bool is_imm8(int value)
>>          return value <= 127 && value >= -128;
>>   }
>>
>> +/*
>> + * Let us limit the positive offset to be <= 124.
> I think the comment will read better if the above says "<= 123",
> since that's the final outcome.
> 124 above is a bit confusing.
> I can tweak while applying if you agree.

Correct. Let us do "<= 123".

>
>> + * to mamximum 123 (0x7b). This way, the jit pass can eventually converge.
> Can fix this typo too.

Sounds good.

Since I need to change test in the second patch (enabling tests for arm64/s390),
let me send v3 to address all comments.