Re: [PATCH] gdb fix for catch-syscall.exp

[John Baldwin <jhb@FreeBSD.org>]

On 11/24/21 9:46 AM, Carl Love wrote:
> On Tue, 2021-11-23 at 14:34 -0800, John Baldwin wrote:
>>>>
> 
> <snip>
> 
>> On 11/23/21 12:34 PM, Simon Marchi wrote:
>>>
>>> The behavior on powerpc sounds like a bug to me, and adjusting the
>>> test
>>> like this patch did just covers it up.  It doesn't make sense for
>>> that
>>> behavior to be different per arch, for the same OS.
>>>
>>> If you all agree that it's a bug, I would suggest reverting this
>>> patch
>>> and making a patch that kfails the test when on powerpc.  And
>>> ideally,
>>> someone should dig to understand why we don't see the return on
>>> powerpc
>>> (and fix it), but I'm not here to tell what other people should
>>> work on
>>> :).
>>
>> I do think this is likely a kernel bug.  In FreeBSD's case we report
>> a single
>> event for both the syscall exit and exec event (but set flags to
>> indicate that
>> both events are present.. in practice for GDB I think this means that
>> on
>> FreeBSD we only report the exec event.  Not sure if it would be more
>> correct
>> to report two events to the core in that case.)  I do think that a
>> given OS
>> should probably be consistent here across architectures.
>>
> 
> So I sent out a preliminary patch for comments to revert the change and
> make it an xfail.

For GDB I think you have to make it an xfail for powerpc.

> I was looking to see where I should file a bug.  The discussion has
> said it is a kernel bug.  The Freebsd commit you pointed to is a distro
> fix from what I can see?  So, is it really a linux kernel issue or
> something that the distros handle?  I believe there is a ptrace code in
> glib see that interacts with the result from the kernel, is that where
> the fix should go to fix all arch?

The FreeBSD commit isn't for a distro, it's for a different OS kernel
that supports (some) Linux binaries as an alternate userspace ABI.  For
the kernel bug you would need to file that with the Linux kernel maintainers
following the directions at
https://www.kernel.org/doc/html/latest/admin-guide/reporting-issues.html

-- 
John Baldwin