[PATCH] linux: spawni.c: simplify error reporting to parent

[Florian Weimer]

On 09/28/2016 08:12 PM, Adhemerval Zanella wrote:
> On 28/09/2016 08:22, Rich Felker wrote:
>> On Wed, Sep 28, 2016 at 05:03:41PM +0200, Andreas Schwab wrote:
>>> On Sep 28 2016, Rich Felker <dalias@libc.org> wrote:
>>>
>>>> This is a bad idea for at least one reason: running under strace seems
>>>> to cause vfork _not_ to wait in the parent, leading to stack
>>>> clobbering and runaway wrong code execution.
>>>
>>> This is not true.  With modern kernels implementing ptrace events a
>>> tracer can correctly handle all clone variants including vfork.
>>
>> The problem might very well be limited to older (but still supported,
>> I think) kernels or older versions of strace; I'm not sure. That's
>> what I meant by saying I don't have a formula to reproduce the issue
>> at the moment.

Rich, I value your comments, I really do, but this isn't actionable 
information, I'm afraid.

> I am not convinced this specific issue should be a blocker for this
> patch.  It seems quite limited in scope (running the process in
> strace) on older/not supported kernel. And the behaviour is clearly
> a kernel issue.
>
> Also I checked with CentOS 6 (2.6.32-642.el6.x86_64, strace 4.8) and
> it seems to follow the expected behaviour.  I would also consider
> any deviation in more recent Linux releases as a kernel regression
> and I see no point and trying to support it.

Agreed, seems reasonable.

Thanks,
Florian