[LTP] max_map_count fail in arm64 system which support lib32

[Cui Bixuan <cuibixuan@huawei.com>]

On 2016/3/22 22:28, Cyril Hrubis wrote:
> Hi!
>> I add a print:
>>
>> #elif defined(__arm__)
>> if (!strncmp(line, "ffff0000-ffff1000", 17))
>>         {
>>                 printf("%s\n", line);  // I add
>>                 return true;
>>         }
>>
>> and then run it(32bit SDK):
> 
> ...
> 
>> So I think:
>> * arm 64bit kernel doesn't have 'special vma VSYSCALL' so no need to skip(32bit binary skip so fail);
>> * arm 32bit kernel have 'special vma VSYSCALL';
> 
> That is what I think as well.
> 
> If you look at the code it does #if defined(__arm__) which is true if
> you compile for 32bit arm, on 64bit __aarch64__ is defined instead.
> 
> Which is why I said we should do runtime check using the machine from
> uname(2) on arm in order to skip the check in case that 32bit arm binary
> runs on 64bit kernel. It should contain something as armvX on 32bit arm
> and aarch64 on 64bit.
Hi,
    I send a patch which uses string check(strstr function) instead of '#if defined' check.
And it contains arm, x86 and ia64.

Thanks,
Cui Bixuan
>