Re: [PATCH V3] glibc: fix create thread failed in old unprivileged docker

["hongxu" <hongxu.jia@windriver.com>]

On 9/1/21 4:11 AM, Richard Purdie wrote:
> [Please note: This e-mail is from an EXTERNAL e-mail address]
>
> On Sun, 2021-08-29 at 19:20 -0700, Hongxu Jia wrote:
>> # Changed in V3: add missing Upstream-Status tag
>>
>> Since upstream commit [d8ea0d0168 Add an internal wrapper for clone, clone2
>> and clone3] applied, start a unprivileged container (docker run without
>> --privileged), it creates a thread failed in container.
>>
>> In commit d8ea0d0168, it calls __clone3 if HAVE_CLONE3_WAPPER is defined.  If
>> __clone3 returns -1 with ENOSYS, fall back to clone or clone2.
>>
>> The newest docker has fixed the issue in commit [1], but it was applied
>> only on master, to backward compatibility with old docker, discussed
>> with glibc maintainer [2], explicitly disable clone3 wrapper work by removing
>> macro definition of HAVE_CLONE3_WRAPPER
>>
>> [1] https://github.com/moby/moby/commit/9f6b562dd12ef7b1f9e2f8e6f2ab6477790a6594
>> [2] https://sourceware.org/pipermail/libc-alpha/2021-August/130591.html
>>
>> Signed-off-by: Hongxu Jia <hongxu.jia@windriver.com>
> Just for reference, I'm going with v1 of this fix.
>
> The reason is that I do want clone3 to work on target and I do want the wrapper
> to be available. Falling back in the EPERM case is therefore easiest.
>
> I did wonder about making the fix nativesdk specific however I decided that was
> going to complicate upgrades and so on a bit too much. The v1 fix is simple
> enough it can be used everywhere without too many side effects.

Absolutely agree

//Hongxu

> Cheers,
>
> Richard
>