1. Time and date of problem: N/A 2. System architecture(s): i386 3. Provide a clear and concise problem description as it is understood at the time of escalation. Please be as specific as possible in your description. Do not use the generic term "hang", as that can mean many things. See IT#237319 for details: Several users complain that their desktop HP DC5850 with RHEL4/SLC4 in 32bit, smp kernel regularly leaves the X11 mouse cursor stuck near the left edge of the X11 screen - it will move briefly right, then jump back to the edge. So far this has only been reported for horizontal movements. A patch exist for RHEL4 (BZ#492129). According to IT#237319 Event posted 2009-10-19 15:09 CEST by alanm: """ This patch isn't in RHEL5 either. If you want to get this into RHEL5 please open a new IT and I'll create a BZ for it. """ 4. Specific action requested of SEG: Please track this bug for RHEL5 too.
Created attachment 365247 [details] xorg-x11-server.1.1.1-mouseaccel-overflow2.patch
Event posted on 2009-10-30 17:45 CET by rdassen In the RHEL4 instance of this issue, bug #492129, there is a reference to an upstream defect (http://bugs.freedesktop.org/show_bug.cgi?id=3113) which has been fixed in http://www.x.org/wiki/Server14Branch through http://cgit.freedesktop.org/xorg/xserver/commit/?id=12d27cf33c6d963eae77795c0d247175907162a5 plus http://cgit.freedesktop.org/xorg/xserver/commit/?id=a66c0f1dca2958835ff65a5b50579e3304ed316a Can you please check whether those patches are relevant to us and whether they may constitute a proper fix? This event sent from IssueTracker by rdassen issue 355615
The issue fixed in 12d27cf addresses a possible integer overflow, leading to the first parameter to pow becoming negative for a sufficiently large dx/dy. In my testing locally, two points were noted: 1. if the first parameter is negative, the return value is NaN and the result is invalid (provided that the second parameter is not an integer). 2. To trigger this overflow, dx/dy needs to be extremely high (greater or equal to 32768). I have never seen deltas go beyond 100, it is unclear if this patch addresses a real-world issue or is merely a cosmetic/safety fix. A comment in Bug 3113 indicates that even with these patches applied, the issue is still present. To get mouse cursor stuck on the left edge dx must be consistently negative. This can only occur if it is indeed negative when passed in from the mouse driver. In that case however, "xset m 5 100" (the workaround from Bug 492129) would not help. It's likely that the reason why the workaround works is because with such a high threshold, the accel code simply isn't triggered anymore. Hence the need for a reproducer, without looking at the values and ensuring what goes on when this bug is triggered, it's hard to even tell if the issue is in the mouse driver or in the server.
Jan, can you give me an update on this please? Have you managed to get the needed output from the debug packages yet?
MODIFIED xorg-x11-server-1.1.1-48.79.el5 is built in brew, please test.
MODIFIED building xorg-x11-server-1.1.1-48.81.el5 in brew.
Confirmed here in QA, I'll verify the fix and check for regressions tomorrow.
Since the problem described in this bug report should be resolved in a recent advisory, it has been closed with a resolution of ERRATA. For information on the advisory, and where to find the updated files, follow the link below. If the solution does not work for you, open a new bug report. http://rhn.redhat.com/errata/RHSA-2012-0303.html