From kde-devel  Fri Dec 16 13:40:53 2022
From: Thiago Macieira <thiago () kde ! org>
Date: Fri, 16 Dec 2022 13:40:53 +0000
To: kde-devel
Subject: Re: Major QDBus regression in Qt6 with potential impact on KDE
Message-Id: <13904546.RDIVbhacDa () tjmaciei-mobl5>
X-MARC-Message: https://marc.info/?l=kde-devel&m=167119764624614

On Thursday, 15 December 2022 18:34:54 -03 Kai Uwe Broulik wrote:
> thanks for bringing that up. Indeed, at least Solid, KDE=E2=80=99s Hardwa=
re
> Abstraction Framework, makes use of InterfacesAdded/InterfacesRemoved
> extensively when talking to UDisks for monitoring storage devices.
>=20
> That said, I haven=E2=80=99t tried Solid on Qt 6 yet, so I don=E2=80=99t =
know if it is a
> real-world issue for this scenario.

The issue appears to be a race condition, because strace shows everything=20
working as it should and the use of QDBUS_DEBUG=3D1 will affect timing. Tha=
t also=20
means the issue is likely a Heisenbug and difficult to debug.

It might also be a latent issue in Qt 5 that got exposed by faster=20
functionality somewhere in QtCore, because there have been no changes to=20
QtDBus to account for this (it has barely received any changes since 5.6).

Someone needs to debug it and I don't have the time.

=2D-=20
Thiago Macieira - thiago (AT) macieira.info - thiago (AT) kde.org
   Software Architect - Intel DCAI Cloud Engineering