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IDProjectCategoryView StatusLast Update
0015831CentOS-7xorg-x11-serverpublic2019-03-05 14:12
Status newResolutionopen 
Product Version7.6.1810 
Target VersionFixed in Version 
Summary0015831: X server crash when starting a particular X client
DescriptionWe have here a custom X client that is used to monitor the status of our telescope. This application has been around for more than 15 years. It has worked on CentOS 7, 6, 5, Fedora 4, RedHat 9 and so on.
Recently with the last xorg-x11-server update on CentOS 7.5 and in CentOS 7.6 when we start our X client the X server crashes. The log contains the following error message

[ 57.084] (EE) Backtrace:
[ 57.084] (EE) 0: /usr/bin/X (xorg_backtrace+0x55) [0x557e4dd73185]
[ 57.084] (EE) 1: /usr/bin/X (0x557e4dbc2000+0x1b4e09) [0x557e4dd76e09]
[ 57.084] (EE) 2: /lib64/ (0x7fd71340e000+0xf5d0) [0x7fd71341d5d0]
[ 57.084] (EE) 3: /usr/bin/X (miHandleValidateExposures+0x29) [0x557e4dd6b9a9]
[ 57.084] (EE) 4: /usr/bin/X (0x557e4dbc2000+0x8652f) [0x557e4dc4852f]
[ 57.084] (EE) 5: /usr/bin/X (ConfigureWindow+0xa94) [0x557e4dc49684]
[ 57.084] (EE) 6: /usr/bin/X (0x557e4dbc2000+0x569b8) [0x557e4dc189b8]
[ 57.084] (EE) 7: /usr/bin/X (0x557e4dbc2000+0x5c35b) [0x557e4dc1e35b]
[ 57.084] (EE) 8: /usr/bin/X (0x557e4dbc2000+0x603aa) [0x557e4dc223aa]
[ 57.084] (EE) 9: /lib64/ (__libc_start_main+0xf5) [0x7fd7130633d5]
[ 57.084] (EE) 10: /usr/bin/X (0x557e4dbc2000+0x4a4ce) [0x557e4dc0c4ce]
[ 57.084] (EE)
[ 57.084] (EE) Segmentation fault at address 0x30000000c
[ 57.084] (EE)
Fatal server error:
[ 57.084] (EE) Caught signal 11 (Segmentation fault). Server aborting

The problem has been introduced in the X server with the patch:

# Bug 1599885 - RFE: enable backing store's Always mode
Patch9750: 0001-composite-Implement-backing-store-Always.patch

Removing such patch and recompiling the X server makes the crash go away.

More information about the crash:
If I start the client without a window manager (startx /usr/bin/myclient) , the X server does not crash.
If I have a desktop with two monitor and I start the client on a non primary output monitor, then the X server does not crash.
If, on a two monitor desktop I start the client on the primary output monitor, or if I have only a single monitor connected (which is, of course, a primary output monitor), then the X server crashes.

I suggest this bug be reported upstream. Since the patch has an RFE attached, they should be make aware that it causes trouble.
Steps To ReproduceSo far I have seen this problem only with our client. So, probably, you wont be able to reproduce it.
TagsNo tags attached.




2019-02-15 16:37

manager   ~0033843

Yes, agree. Report it upstream please and then cross link the 2 bug entries so each tracker is aware of the other one. You want


2019-02-15 17:11

reporter   ~0033844

Issue History

Date Modified Username Field Change
2019-02-15 16:13 gcomes New Issue
2019-02-15 16:37 TrevorH Note Added: 0033843
2019-02-15 17:11 gcomes Note Added: 0033844