> On 16-Nov-2023, at 6:56 PM, Ani Sinha <anisi...@redhat.com> wrote:
>
>
>
>> On 16-Nov-2023, at 5:23 PM, Nicholas Piggin <npig...@gmail.com> wrote:
>>
>> Like replay_linux.py, reverse_debugging.py starts the vm with console
>> set but does not interact with it (e.g., with wait_for_console_pattern).
>> In this situation, the console should have a drainer attached so the
>> socket does not fill. replay_linux.py has a drainer, but it is missing
>> from reverse_debugging.py.
>>
>> Per analysis in Link: this can cause the console socket/pipe to fill and
>> QEMU get stuck in qemu_chr_write_buffer, leading to strange test case
>> failures (ppc64 fails because it prints a lot to console in early bios).
>> Attaching a drainer prevents this.
>>
>> Note, this commit does not fix bugs introduced by the commits referenced
>> in the first two Fixes: tags, but together those commits conspire to
>> irritate the problem and cause test case failure, which this commit
>> fixes.
>>
>> Link: https://lore.kernel.org/qemu-devel/zvt-by9yor69q...@redhat.com/
>> Fixes: 1d4796cd0083 ("python/machine: use socketpair() for console
>> connections")
>> Fixes: 761a13b23946 ("tests/avocado: ppc64 reverse debugging tests for
>> pseries and powernv")
>> Fixes: be52eca30978 ("tests/acceptance: add reverse debugging test")
>> Tested-by: Thomas Huth <th...@redhat.com>
>> Signed-off-by: Nicholas Piggin <npig...@gmail.com>
>
> Reviewed-by: Ani Sinha <anisi...@redhat.com <mailto:anisi...@redhat.com>>
This bs started happening recently once I upgraded my OS. Sorry about that.
Reviewed-by: Ani Sinha <anisi...@redhat.com <mailto:anisi...@redhat.com>>
>
>> ---
>> tests/avocado/reverse_debugging.py | 5 +++++
>> 1 file changed, 5 insertions(+)
>>
>> diff --git a/tests/avocado/reverse_debugging.py
>> b/tests/avocado/reverse_debugging.py
>> index fc47874eda..128d85bc0e 100644
>> --- a/tests/avocado/reverse_debugging.py
>> +++ b/tests/avocado/reverse_debugging.py
>> @@ -12,6 +12,7 @@
>>
>> from avocado import skipIf
>> from avocado_qemu import BUILD_DIR
>> +from avocado.utils import datadrainer
>> from avocado.utils import gdb
>> from avocado.utils import process
>> from avocado.utils.network.ports import find_free_port
>> @@ -52,6 +53,10 @@ def run_vm(self, record, shift, args, replay_path,
>> image_path, port):
>> if args:
>> vm.add_args(*args)
>> vm.launch()
>> + console_drainer = datadrainer.LineLogger(vm.console_socket.fileno(),
>> + logger=self.log.getChild('console'),
>> + stop_check=(lambda : not
>> vm.is_running()))
>> + console_drainer.start()
>> return vm
>>
>> @staticmethod
>> --
>> 2.42.0
