From kde-core-devel Fri May 28 12:04:15 2010 From: Lubos Lunak Date: Fri, 28 May 2010 12:04:15 +0000 To: kde-core-devel Subject: Re: Review Request: Workaround for non-thread-safety of Message-Id: <201005281404.15445.l.lunak () suse ! cz> X-MARC-Message: https://marc.info/?l=kde-core-devel&m=127504829131651 On Friday 28 of May 2010, Thiago Macieira wrote: > Em Sexta-feira 28. Maio 2010, às 01.17.47, Lubos Lunak escreveu: > > For example, openSUSE 11.3 is now entering RC phase and that means that > > only fixes can enter it, not features or newer non-patchlevel releases. > > Since the fix is in 1.4.0 and openSUSE is at 1.2.8 IIRC, 1.4.0 cannot > > enter openSUSE 11.3, neither now nor later. Now I know what the fix is > > and I need to know what the actual problems are to evaluate and possibly > > justify a request for exception to the rules. With the information given > > so far the fix appears to be rather risky and not even remotely worth a > > problem that has existed for quite a while and is "theoretical". > > It's not theoretical. It's quite easy to run into that issue: if the mutex > is unlocked for a callback, the other thread will not be able to send the > message. It will fail. You don't understand - for me as a packager, this all is completely uninteresting so far. Thread safety problem with D-Bus? If a mutex is unlocked, other thread will not be able to send a message? And the fix is a new minor release? I don't need five seconds to shrug this off. Let me try to explain this way: Suppose I'd give you a 1000-line patch for Qt that'd rewrite a part of QClipboard internals because the Xlib locking there was wrong and said you should include it in Qt4.6.3 . That's like what you've done. You are missing the equivalent of "without the fix Qt applications may randomly crash as a result of copy&pasting in any app". > I've seen krunner crashing because of this. That happens because the D-Bus > calls are sent by several threads in response to the same event: the user > typing. KRunner auto-restarts and apparently the crash isn't that common. Not even close to justifying doing anything special about it. > Anyway, QtDBus is resistant to the change and wouldn't have problems with > the patch. The problem are other bindings and low-level apps. -- Lubos Lunak openSUSE Boosters team, KDE developer l.lunak@suse.cz , l.lunak@kde.org