KAlarm would crash randomly but infrequently when it triggers an audio alarm. After I re-ran KAlarm from the terminal (e.g. Konsole), it turns out that the crash was caused by an assertion error with Pulseaudio. STEPS TO REPRODUCE 1. Create a recurring audio alarm 2. Wait patiently until KAlarm refuses to play the alarm and crashes OBSERVED RESULT KAlarm crashed silently at the exact moment when it should be playing the alarm. This occurred around 10% of the time, probably at least once a week on my end. Otherwise, the alarm played as usual. Since I had Dr. Konqi installed, the crash would also cause its window to appear, but when running KAlarm from the terminal, it would just crash silently, i.e. the Dr. Konqi window doesn't appear. Either way, Dr. Konqi would fail to get a stack trace from the crash. EXPECTED RESULT Alarm plays as usual, and KAlarm does not crash. SOFTWARE/OS VERSIONS KAlarm version: 2.13.3, Akonadi version Linux: Kernel version 5.5, Manjaro distro KDE Plasma Version: 5.18.3 KDE Frameworks Version: 5.68.0 Qt Version: 5.14.1 ADDITIONAL INFORMATION The alarm used for reproducing the crashes had its occurrence set to every hour. Because I run my computer 24/7 with occasional reboots at least weekly for updates, I set the alarm to run only during working hours, which was set in the app settings to 8am-11pm every day. When I reproduced the crash, my computer was already playing music from another app without any issues. In my case, I was playing music from Spotify through its official desktop app. I've also encountered this crash weekly since around two months ago, when I had Plasma 5.17 and an older version of Frameworks installed. journalctl logs: Apr 04 10:24:00 manjaro audit[10147]: ANOM_ABEND auid=1000 uid=1000 gid=1000 ses=2 subj==unconfined pid=10147 comm="threaded-ml" exe="/usr/bin/kalarm" sig=6 res=1 Apr 04 10:24:00 manjaro kernel: audit: type=1701 audit(1586017440.072:152): auid=1000 uid=1000 gid=1000 ses=2 subj==unconfined pid=10147 comm="threaded-ml" exe="/usr/bin/kalarm" sig=6 res=1 Apr 04 10:24:00 manjaro akonadiserver[1566]: org.kde.pim.akonadiserver: Subscriber "kalarm-48271 - 94270372983040" disconnected Apr 04 10:24:00 manjaro audit[1]: SERVICE_START pid=1 uid=0 auid=4294967295 ses=4294967295 subj==unconfined msg='unit=systemd-coredump@1-45471-0 comm="systemd" exe="/usr/lib/systemd/systemd" hostname=? addr=? terminal=? res=success' Apr 04 10:24:00 manjaro kded5[1135]: Service ":1.226" unregistered Apr 04 10:24:00 manjaro kernel: audit: type=1130 audit(1586017440.082:153): pid=1 uid=0 auid=4294967295 ses=4294967295 subj==unconfined msg='unit=systemd-coredump@1-45471-0 comm="systemd" exe="/usr/lib/systemd/systemd" hostname=? addr=? terminal=? res=success' Apr 04 10:24:00 manjaro systemd[1]: Started Process Core Dump (PID 45471/UID 0). Apr 04 10:24:00 manjaro kded5[1135]: Registering ":1.505/StatusNotifierItem" to system tray Apr 04 10:24:01 manjaro systemd-coredump[45477]: Process 10147 (kalarm) of user 1000 dumped core. Stack trace of thread 45468: #0 0x00007f2247c4cce5 raise (libc.so.6 + 0x3bce5) #1 0x00007f2249a72bf0 _ZN6KCrash19defaultCrashHandlerEi (libKF5Crash.so.5 + 0x4bf0) #2 0x00007f2247c4cd70 __restore_rt (libc.so.6 + 0x3bd70) #3 0x00007f2247c4cce5 raise (libc.so.6 + 0x3bce5) #4 0x00007f2247c36857 abort (libc.so.6 + 0x25857) #5 0x00007f2245c4cc7f pa_fdsem_post (libpulsecommon-13.0.so + 0x41c7f) #6 0x00007f2245c345d9 pa_srbchannel_write (libpulsecommon-13.0.so + 0x295d9) #7 0x00007f2245c35c36 n/a (libpulsecommon-13.0.so + 0x2ac36) #8 0x00007f2245c36e7b n/a (libpulsecommon-13.0.so + 0x2be7b) #9 0x00007f2245c37027 n/a (libpulsecommon-13.0.so + 0x2c027) #10 0x00007f2245c3443a n/a (libpulsecommon-13.0.so + 0x2943a) #11 0x00007f224785bb93 pa_mainloop_dispatch (libpulse.so.0 + 0x21b93) #12 0x00007f224785f311 pa_mainloop_iterate (libpulse.so.0 + 0x25311) #13 0x00007f224785f3b1 pa_mainloop_run (libpulse.so.0 + 0x253b1) #14 0x00007f224784f61e n/a (libpulse.so.0 + 0x1561e) #15 0x00007f2245c28d1c n/a (libpulsecommon-13.0.so + 0x1dd1c) #16 0x00007f2246d0746f start_thread (libpthread.so.0 + 0x946f) #17 0x00007f2247d103d3 __clone (libc.so.6 + 0xff3d3) Stack trace of thread 45469: #0 0x00007f2245f61530 n/a (libglib-2.0.so.0 + 0x4f530) #1 0x00007f2245f61663 n/a (libglib-2.0.so.0 + 0x4f663) #2 0x00007f2245f618da n/a (libglib-2.0.so.0 + 0x4f8da) #3 0x00007f2245f646c5 g_sequence_sort_iter (libglib-2.0.so.0 + 0x526c5) #4 0x00007f2245f647a8 g_sequence_sort (libglib-2.0.so.0 + 0x527a8) #5 0x00007f222e768a75 n/a (libgstplayback.so + 0x32a75) #6 0x00007f222e768d72 n/a (libgstplayback.so + 0x32d72) #7 0x00007f2240d3469a ffi_call_unix64 (libffi.so.6 + 0x669a) #8 0x00007f2240d33fb6 ffi_call (libffi.so.6 + 0x5fb6) #9 0x00007f222f6cf59e g_cclosure_marshal_generic (libgobject-2.0.so.0 + 0x3d59e) #10 0x00007f222f6d061a g_closure_invoke (libgobject-2.0.so.0 + 0x3e61a) #11 0x00007f222f6b197e n/a (libgobject-2.0.so.0 + 0x1f97e) #12 0x00007f222f6b45cc g_signal_emit_valist (libgobject-2.0.so.0 + 0x225cc) #13 0x00007f222f6b66b0 g_signal_emit (libgobject-2.0.so.0 + 0x246b0) #14 0x00007f222e782752 n/a (libgstplayback.so + 0x4c752) #15 0x00007f2240d3469a ffi_call_unix64 (libffi.so.6 + 0x669a) #16 0x00007f2240d33fb6 ffi_call (libffi.so.6 + 0x5fb6) #17 0x00007f222f6cf59e g_cclosure_marshal_generic (libgobject-2.0.so.0 + 0x3d59e) #18 0x00007f222f6d061a g_closure_invoke (libgobject-2.0.so.0 + 0x3e61a) #19 0x00007f222f6b197e n/a (libgobject-2.0.so.0 + 0x1f97e) #20 0x00007f222f6b45cc g_signal_emit_valist (libgobject-2.0.so.0 + 0x225cc) #21 0x00007f222f6b66b0 g_signal_emit (libgobject-2.0.so.0 + 0x246b0) #22 0x00007f222e79cf38 n/a (libgstplayback.so + 0x66f38) #23 0x00007f222e79a74d n/a (libgstplayback.so + 0x6474d) #24 0x00007f2240d3469a ffi_call_unix64 (libffi.so.6 + 0x669a) #25 0x00007f2240d33fb6 ffi_call (libffi.so.6 + 0x5fb6) #26 0x00007f222f6cf59e g_cclosure_marshal_generic (libgobject-2.0.so.0 + 0x3d59e) #27 0x00007f222f6d061a g_closure_invoke (libgobject-2.0.so.0 + 0x3e61a) #28 0x00007f222f6b197e n/a (libgobject-2.0.so.0 + 0x1f97e) #29 0x00007f222f6b4ab9 g_signal_emit_valist (libgobject-2.0.so.0 + 0x22ab9) #30 0x00007f222f6b66b0 g_signal_emit (libgobject-2.0.so.0 + 0x246b0) #31 0x00007f222e7d185e n/a (libgstcoreelements.so + 0xc85e) #32 0x00007f222f73c3f9 n/a (libgstreamer-1.0.so.0 + 0x4b3f9) #33 0x00007f2245f544e7 n/a (libglib-2.0.so.0 + 0x424e7) #34 0x00007f2245f56e71 n/a (libglib-2.0.so.0 + 0x44e71) #35 0x00007f2246d0746f start_thread (libpthread.so.0 + 0x946f) #36 0x00007f2247d103d3 __clone (libc.so.6 + 0xff3d3) Stack trace of thread 10148: #0 0x00007f2247d05abf __poll (libc.so.6 + 0xf4abf) #1 0x00007f2246f2f63b n/a (libxcb.so.1 + 0xc63b) #2 0x00007f2246f3137b xcb_wait_for_event (libxcb.so.1 + 0xe37b) #3 0x00007f224222dba1 n/a (libQt5XcbQpa.so.5 + 0x65ba1) #4 0x00007f22480a5fd6 n/a (libQt5Core.so.5 + 0xc9fd6) #5 0x00007f2246d0746f start_thread (libpthread.so.0 + 0x946f) #6 0x00007f2247d103d3 __clone (libc.so.6 + 0xff3d3) Stack trace of thread 10147: #0 0x00007f2247d05abf __poll (libc.so.6 + 0xf4abf) #1 0x00007f2249a71696 n/a (libKF5Crash.so.5 + 0x3696) #2 0x00007f2249a71c31 n/a (libKF5Crash.so.5 + 0x3c31) #3 0x00007f2249a72521 n/a (libKF5Crash.so.5 + 0x4521) #4 0x00007f2249a72a6e _ZN6KCrash19defaultCrashHandlerEi (libKF5Crash.so.5 + 0x4a6e) #5 0x00007f2247c4cd70 __restore_rt (libc.so.6 + 0x3bd70) #6 0x00007f2247c4cce5 raise (libc.so.6 + 0x3bce5) #7 0x00007f2247c36857 abort (libc.so.6 + 0x25857) #8 0x00007f2247855c54 n/a (libpulse.so.0 + 0x1bc54) #9 0x00007f2247867de0 n/a (libpulse.so.0 + 0x2dde0) #10 0x00007f2245c3e684 n/a (libpulsecommon-13.0.so + 0x33684) #11 0x00007f2245c3e9ff pa_pdispatch_run (libpulsecommon-13.0.so + 0x339ff) #12 0x00007f2247871f01 n/a (libpulse.so.0 + 0x37f01) #13 0x00007f2245c35339 n/a (libpulsecommon-13.0.so + 0x2a339) #14 0x00007f2245c36e8b n/a (libpulsecommon-13.0.so + 0x2be8b) #15 0x00007f2245c37027 n/a (libpulsecommon-13.0.so + 0x2c027) #16 0x00007f2245c3443a n/a (libpulsecommon-13.0.so + 0x2943a) #17 0x00007f2247835dd6 n/a (libpulse-mainloop-glib.so.0 + 0x1dd6) #18 0x00007f2245f7d9be g_main_context_dispatch (libglib-2.0.so.0 + 0x6b9be) #19 0x00007f2245f7f831 n/a (libglib-2.0.so.0 + 0x6d831) #20 0x00007f2245f7f871 g_main_context_iteration (libglib-2.0.so.0 + 0x6d871) #21 0x00007f22482da0ec _ZN20QEventDispatcherGlib13processEventsE6QFlagsIN10QEventLoop17ProcessEventsFlagEE (libQt5Core.so.5 + 0x2fe0ec) #22 0x00007f224828057c _ZN10QEventLoop4execE6QFlagsINS_17ProcessEventsFlagEE (libQt5Core.so.5 + 0x2a457c) #23 0x00007f2248288586 _ZN16QCoreApplication4execEv (libQt5Core.so.5 + 0x2ac586) #24 0x000055bd0760c3bd n/a (kalarm + 0x8e3bd) #25 0x00007f2247c38023 __libc_start_main (libc.so.6 + 0x27023) #26 0x000055bd0760cd2e n/a (kalarm + 0x8ed2e) Stack trace of thread 10150: #0 0x00007f2247d05abf __poll (libc.so.6 + 0xf4abf) #1 0x00007f2245f7f7a0 n/a (libglib-2.0.so.0 + 0x6d7a0) #2 0x00007f2245f7f871 g_main_context_iteration (libglib-2.0.so.0 + 0x6d871) #3 0x00007f22482da0d0 _ZN20QEventDispatcherGlib13processEventsE6QFlagsIN10QEventLoop17ProcessEventsFlagEE (libQt5Core.so.5 + 0x2fe0d0) #4 0x00007f224828057c _ZN10QEventLoop4execE6QFlagsINS_17ProcessEventsFlagEE (libQt5Core.so.5 + 0x2a457c) #5 0x00007f22480a4e62 _ZN7QThread4execEv (libQt5Core.so.5 + 0xc8e62) #6 0x00007f22480a5fd6 n/a (libQt5Core.so.5 + 0xc9fd6) #7 0x00007f2246d0746f start_thread (libpthread.so.0 + 0x946f) #8 0x00007f2247d103d3 __clone (libc.so.6 + 0xff3d3) Stack trace of thread 10149: #0 0x00007f2247d05abf __poll (libc.so.6 + 0xf4abf) #1 0x00007f2245f7f7a0 n/a (libglib-2.0.so.0 + 0x6d7a0) #2 0x00007f2245f7f871 g_main_context_iteration (libglib-2.0.so.0 + 0x6d871) #3 0x00007f22482da0d0 _ZN20QEventDispatcherGlib13processEventsE6QFlagsIN10QEventLoop17ProcessEventsFlagEE (libQt5Core.so.5 + 0x2fe0d0) #4 0x00007f224828057c _ZN10QEventLoop4execE6QFlagsINS_17ProcessEventsFlagEE (libQt5Core.so.5 + 0x2a457c) #5 0x00007f22480a4e62 _ZN7QThread4execEv (libQt5Core.so.5 + 0xc8e62) #6 0x00007f22485d4b28 n/a (libQt5DBus.so.5 + 0x15b28) #7 0x00007f22480a5fd6 n/a (libQt5Core.so.5 + 0xc9fd6) #8 0x00007f2246d0746f start_thread (libpthread.so.0 + 0x946f) #9 0x00007f2247d103d3 __clone (libc.so.6 + 0xff3d3) Stack trace of thread 45465: #0 0x00007f2247d05abf __poll (libc.so.6 + 0xf4abf) #1 0x00007f2245f7f7a0 n/a (libglib-2.0.so.0 + 0x6d7a0) #2 0x00007f2245f7f871 g_main_context_iteration (libglib-2.0.so.0 + 0x6d871) #3 0x00007f22482da0d0 _ZN20QEventDispatcherGlib13processEventsE6QFlagsIN10QEventLoop17ProcessEventsFlagEE (libQt5Core.so.5 + 0x2fe0d0) #4 0x00007f224828057c _ZN10QEventLoop4execE6QFlagsINS_17ProcessEventsFlagEE (libQt5Core.so.5 + 0x2a457c) #5 0x00007f22480a4e62 _ZN7QThread4execEv (libQt5Core.so.5 + 0xc8e62) #6 0x000055bd076993de n/a (kalarm + 0x11b3de) #7 0x00007f22480a5fd6 n/a (libQt5Core.so.5 + 0xc9fd6) #8 0x00007f2246d0746f start_thread (libpthread.so.0 + 0x946f) #9 0x00007f2247d103d3 __clone (libc.so.6 + 0xff3d3) Apr 04 10:24:01 manjaro systemd[1]: systemd-coredump@1-45471-0.service: Succeeded. Terminal output during crash: Assertion '*_head == _item' failed at ../pulseaudio/src/pulse/operation.c:85, function operation_unlink(). Aborting. KCrash: crashing... crashRecursionCounter = 2 KCrash: Application Name = kalarm path = /usr/bin pid = 10147 KCrash: Arguments: /usr/bin/kalarm KCrash: Attempting to start /usr/lib/drkonqi from kdeinit sock_file=/run/user/1000/kdeinit5__0 pa_write() failed while trying to wake up the mainloop: Bad file descriptor pa_write() failed while trying to wake up the mainloop: Bad file descriptor pa_write() failed while trying to wake up the mainloop: Bad file descriptor Invalid write to eventfd: Bad file descriptor Code should not be reached at ../pulseaudio/src/pulsecore/fdsem.c:199, function pa_fdsem_post(). Aborting. Unable to start Dr. Konqi Re-raising signal for core dump handling. [1] 10147 abort (core dumped) kalarm
Earlier today, I got KAlarm to crash when I clicked on "Try" on the bottom of the alarm properties dialog for an audio alarm with "Set Volume" checked and its slider already set to below the maximum level. I have not yet encountered crashes when playing alarms without "Set Volume" enabled. So I've changed the title of this ticket to reflect this. Here are the new steps to reproduce this bug: 1. Create an audio alarm 2. Enable the "Set Volume" checkbox 3. Save the alarm 4. Open the properties dialog again for the same alarm 5. Click on "Try" several times until the window disappears Alternatively, after saving the alarm, you can wait for it to trigger and note the crash, but I recommend the above steps to reproduce the crash faster.
With the earlier observations, I got different error messages in terminal exactly at the time of each crash, but they still seem to blame PulseAudio. For the first crash, I got: ERROR:../pulseaudio/src/pulse/glib-mainloop.c:490:prepare_func: assertion failed: (t) Bail out! ERROR:../pulseaudio/src/pulse/glib-mainloop.c:490:prepare_func: assertion failed: (t) And for the second crash: Assertion 'pa_atomic_load(&(o)->_ref) >= 1' failed at ../pulseaudio/src/pulse/operation.c:123, function pa_operation_cancel(). Aborting. ----- Here is the stack trace from journalctl for the first crash: Process 22551 (kalarm) of user 1000 dumped core. Stack trace of thread 23173: #0 0x00007f470cf7ece5 raise (libc.so.6 + 0x3bce5) #1 0x00007f470eda6bf0 _ZN6KCrash19defaultCrashHandlerEi (libKF5Crash.so.5 + 0x4bf0) #2 0x00007f470cf7ed70 __restore_rt (libc.so.6 + 0x3bd70) #3 0x00007f470cf7ece5 raise (libc.so.6 + 0x3bce5) #4 0x00007f470cf68857 abort (libc.so.6 + 0x25857) #5 0x00007f470cf68727 __assert_fail_base.cold (libc.so.6 + 0x25727) #6 0x00007f470cf77426 __assert_fail (libc.so.6 + 0x34426) #7 0x00007f470c03ba46 __pthread_mutex_lock_full (libpthread.so.0 + 0xba46) #8 0x00007f470af69dff pa_mutex_lock (libpulsecommon-13.0.so + 0x2ddff) #9 0x00007f470cb79c20 n/a (libpulse.so.0 + 0xdc20) #10 0x00007f470cb87059 pa_mainloop_poll (libpulse.so.0 + 0x1b059) #11 0x00007f470cb91301 pa_mainloop_iterate (libpulse.so.0 + 0x25301) #12 0x00007f470cb913b1 pa_mainloop_run (libpulse.so.0 + 0x253b1) #13 0x00007f470cb8161e n/a (libpulse.so.0 + 0x1561e) #14 0x00007f470af59d1c n/a (libpulsecommon-13.0.so + 0x1dd1c) #15 0x00007f470c03946f start_thread (libpthread.so.0 + 0x946f) #16 0x00007f470d0423d3 __clone (libc.so.6 + 0xff3d3) Stack trace of thread 22551: #0 0x00007f470c03fcf5 pthread_cond_wait@@GLIBC_2.3.2 (libpthread.so.0 + 0xfcf5) #1 0x00007f470c261819 n/a (libxcb.so.1 + 0xc819) #2 0x00007f470c26308f n/a (libxcb.so.1 + 0xe08f) #3 0x00007f470c2631a2 xcb_wait_for_reply (libxcb.so.1 + 0xe1a2) #4 0x00007f470753354c _ZN14QXcbConnection4syncEv (libQt5XcbQpa.so.5 + 0x3b54c) #5 0x00007f470754edfc n/a (libQt5XcbQpa.so.5 + 0x56dfc) #6 0x00007f470754f100 n/a (libQt5XcbQpa.so.5 + 0x57100) #7 0x00007f470dca7755 _ZN13QBackingStore10beginPaintERK7QRegion (libQt5Gui.so.5 + 0x2f5755) #8 0x00007f470e1cc409 n/a (libQt5Widgets.so.5 + 0x16e409) #9 0x00007f470e1ccfe4 n/a (libQt5Widgets.so.5 + 0x16efe4) #10 0x00007f470e1f6d27 _ZN14QWidgetPrivate16syncBackingStoreEv (libQt5Widgets.so.5 + 0x198d27) #11 0x00007f470e1fdd14 _ZN7QWidget5eventEP6QEvent (libQt5Widgets.so.5 + 0x19fd14) #12 0x00007f470e1b9352 _ZN19QApplicationPrivate13notify_helperEP7QObjectP6QEvent (libQt5Widgets.so.5 + 0x15b352) #13 0x00007f470e1c2829 _ZN12QApplication6notifyEP7QObjectP6QEvent (libQt5Widgets.so.5 + 0x164829) #14 0x00007f470d5b34f2 _ZN16QCoreApplication15notifyInternal2EP7QObjectP6QEvent (libQt5Core.so.5 + 0x2a54f2) #15 0x00007f470d5b5d56 _ZN23QCoreApplicationPrivate16sendPostedEventsEP7QObjectiP11QThreadData (libQt5Core.so.5 + 0x2a7d56) #16 0x00007f470d60c244 n/a (libQt5Core.so.5 + 0x2fe244) #17 0x00007f470b2ae9be g_main_context_dispatch (libglib-2.0.so.0 + 0x6b9be) #18 0x00007f470b2b0831 n/a (libglib-2.0.so.0 + 0x6d831) #19 0x00007f470b2b0871 g_main_context_iteration (libglib-2.0.so.0 + 0x6d871) #20 0x00007f470d60b890 _ZN20QEventDispatcherGlib13processEventsE6QFlagsIN10QEventLoop17ProcessEventsFlagEE (libQt5Core.so.5 + 0x2fd890) #21 0x00007f470d5b205c _ZN10QEventLoop4execE6QFlagsINS_17ProcessEventsFlagEE (libQt5Core.so.5 + 0x2a405c) #22 0x00007f470e3c77de _ZN7QDialog4execEv (libQt5Widgets.so.5 + 0x3697de) #23 0x0000562d31849364 n/a (kalarm + 0x160364) #24 0x0000562d31858410 n/a (kalarm + 0x16f410) #25 0x00007f470e42f708 n/a (libQt5Widgets.so.5 + 0x3d1708) #26 0x00007f470e4353e7 _ZN17QAbstractItemView4editERK11QModelIndexNS_11EditTriggerEP6QEvent (libQt5Widgets.so.5 + 0x3d73e7) #27 0x00007f470e4a88d4 _ZN9QTreeView21mouseDoubleClickEventEP11QMouseEvent (libQt5Widgets.so.5 + 0x44a8d4) #28 0x00007f470e1fd8b9 _ZN7QWidget5eventEP6QEvent (libQt5Widgets.so.5 + 0x19f8b9) #29 0x00007f470e2aecbf _ZN6QFrame5eventEP6QEvent (libQt5Widgets.so.5 + 0x250cbf) #30 0x00007f470e439d70 _ZN17QAbstractItemView13viewportEventEP6QEvent (libQt5Widgets.so.5 + 0x3dbd70) #31 0x00007f470e4aac7c _ZN9QTreeView13viewportEventEP6QEvent (libQt5Widgets.so.5 + 0x44cc7c) #32 0x0000562d3185892d n/a (kalarm + 0x16f92d) #33 0x00007f470d5b3203 _ZN23QCoreApplicationPrivate29sendThroughObjectEventFiltersEP7QObjectP6QEvent (libQt5Core.so.5 + 0x2a5203) #34 0x00007f470e1b9341 _ZN19QApplicationPrivate13notify_helperEP7QObjectP6QEvent (libQt5Widgets.so.5 + 0x15b341) #35 0x00007f470e1c2a78 _ZN12QApplication6notifyEP7QObjectP6QEvent (libQt5Widgets.so.5 + 0x164a78) #36 0x00007f470d5b34f2 _ZN16QCoreApplication15notifyInternal2EP7QObjectP6QEvent (libQt5Core.so.5 + 0x2a54f2) #37 0x00007f470e1c1aeb _ZN19QApplicationPrivate14sendMouseEventEP7QWidgetP11QMouseEventS1_S1_PS1_R8QPointerIS0_Ebb (libQt5Widgets.so.5 + 0x163aeb) #38 0x00007f470e218b21 n/a (libQt5Widgets.so.5 + 0x1bab21) #39 0x00007f470e21baa4 n/a (libQt5Widgets.so.5 + 0x1bdaa4) #40 0x00007f470e1b9352 _ZN19QApplicationPrivate13notify_helperEP7QObjectP6QEvent (libQt5Widgets.so.5 + 0x15b352) #41 0x00007f470e1c2829 _ZN12QApplication6notifyEP7QObjectP6QEvent (libQt5Widgets.so.5 + 0x164829) #42 0x00007f470d5b34f2 _ZN16QCoreApplication15notifyInternal2EP7QObjectP6QEvent (libQt5Core.so.5 + 0x2a54f2) #43 0x00007f470dae61f5 _ZN22QGuiApplicationPrivate17processMouseEventEPN29QWindowSystemInterfacePrivate10MouseEventE (libQt5Gui.so.5 + 0x1341f5) #44 0x00007f470dae79b6 _ZN22QGuiApplicationPrivate24processWindowSystemEventEPN29QWindowSystemInterfacePrivate17WindowSystemEventE (libQt5Gui.so.5 + 0x1359b6) #45 0x00007f470dabfc5c _ZN22QWindowSystemInterface22sendWindowSystemEventsE6QFlagsIN10QEventLoop17ProcessEventsFlagEE (libQt5Gui.so.5 + 0x10dc5c) #46 0x00007f470755ee2c n/a (libQt5XcbQpa.so.5 + 0x66e2c) #47 0x00007f470b2ae9be g_main_context_dispatch (libglib-2.0.so.0 + 0x6b9be) #48 0x00007f470b2b0831 n/a (libglib-2.0.so.0 + 0x6d831) #49 0x00007f470b2b0871 g_main_context_iteration (libglib-2.0.so.0 + 0x6d871) #50 0x00007f470d60b890 _ZN20QEventDispatcherGlib13processEventsE6QFlagsIN10QEventLoop17ProcessEventsFlagEE (libQt5Core.so.5 + 0x2fd890) #51 0x00007f470d5b205c _ZN10QEventLoop4execE6QFlagsINS_17ProcessEventsFlagEE (libQt5Core.so.5 + 0x2a405c) #52 0x00007f470d5ba066 _ZN16QCoreApplication4execEv (libQt5Core.so.5 + 0x2ac066) #53 0x0000562d317773bd n/a (kalarm + 0x8e3bd) #54 0x00007f470cf6a023 __libc_start_main (libc.so.6 + 0x27023) #55 0x0000562d31777d2e n/a (kalarm + 0x8ed2e) Stack trace of thread 22553: #0 0x00007f470b2affc4 g_main_context_prepare (libglib-2.0.so.0 + 0x6cfc4) #1 0x00007f470b2b06c6 n/a (libglib-2.0.so.0 + 0x6d6c6) #2 0x00007f470b2b0871 g_main_context_iteration (libglib-2.0.so.0 + 0x6d871) #3 0x00007f470d60b8ac _ZN20QEventDispatcherGlib13processEventsE6QFlagsIN10QEventLoop17ProcessEventsFlagEE (libQt5Core.so.5 + 0x2fd8ac) #4 0x00007f470d5b205c _ZN10QEventLoop4execE6QFlagsINS_17ProcessEventsFlagEE (libQt5Core.so.5 + 0x2a405c) #5 0x00007f470d3d6c62 _ZN7QThread4execEv (libQt5Core.so.5 + 0xc8c62) #6 0x00007f470d906b28 n/a (libQt5DBus.so.5 + 0x15b28) #7 0x00007f470d3d7dd6 n/a (libQt5Core.so.5 + 0xc9dd6) #8 0x00007f470c03946f start_thread (libpthread.so.0 + 0x946f) #9 0x00007f470d0423d3 __clone (libc.so.6 + 0xff3d3) Stack trace of thread 22554: #0 0x00007f470cfc89d3 __libc_enable_asynccancel (libc.so.6 + 0x859d3) #1 0x00007f470d037aa7 __poll (libc.so.6 + 0xf4aa7) #2 0x00007f470b2b07a0 n/a (libglib-2.0.so.0 + 0x6d7a0) #3 0x00007f470b2b0871 g_main_context_iteration (libglib-2.0.so.0 + 0x6d871) #4 0x00007f470d60b8ac _ZN20QEventDispatcherGlib13processEventsE6QFlagsIN10QEventLoop17ProcessEventsFlagEE (libQt5Core.so.5 + 0x2fd8ac) #5 0x00007f470d5b205c _ZN10QEventLoop4execE6QFlagsINS_17ProcessEventsFlagEE (libQt5Core.so.5 + 0x2a405c) #6 0x00007f470d3d6c62 _ZN7QThread4execEv (libQt5Core.so.5 + 0xc8c62) #7 0x00007f470d3d7dd6 n/a (libQt5Core.so.5 + 0xc9dd6) #8 0x00007f470c03946f start_thread (libpthread.so.0 + 0x946f) #9 0x00007f470d0423d3 __clone (libc.so.6 + 0xff3d3) Stack trace of thread 23174: #0 0x00007f470d03cf8d syscall (libc.so.6 + 0xf9f8d) #1 0x00007f470b25f531 g_cond_wait (libglib-2.0.so.0 + 0x1c531) #2 0x00007f46f4b89603 n/a (libgstreamer-1.0.so.0 + 0x4b603) #3 0x00007f470b2854e7 n/a (libglib-2.0.so.0 + 0x424e7) #4 0x00007f470b287e71 n/a (libglib-2.0.so.0 + 0x44e71) #5 0x00007f470c03946f start_thread (libpthread.so.0 + 0x946f) #6 0x00007f470d0423d3 __clone (libc.so.6 + 0xff3d3) Stack trace of thread 23170: #0 0x00007f470d03cf8d syscall (libc.so.6 + 0xf9f8d) #1 0x00007f470b25f531 g_cond_wait (libglib-2.0.so.0 + 0x1c531) #2 0x00007f46f4b89603 n/a (libgstreamer-1.0.so.0 + 0x4b603) #3 0x00007f470b2854e7 n/a (libglib-2.0.so.0 + 0x424e7) #4 0x00007f470b287e71 n/a (libglib-2.0.so.0 + 0x44e71) #5 0x00007f470c03946f start_thread (libpthread.so.0 + 0x946f) #6 0x00007f470d0423d3 __clone (libc.so.6 + 0xff3d3) Stack trace of thread 23175: #0 0x00007f470d03cf8d syscall (libc.so.6 + 0xf9f8d) #1 0x00007f470b25f531 g_cond_wait (libglib-2.0.so.0 + 0x1c531) #2 0x00007f46f4b89603 n/a (libgstreamer-1.0.so.0 + 0x4b603) #3 0x00007f470b2854e7 n/a (libglib-2.0.so.0 + 0x424e7) #4 0x00007f470b287e71 n/a (libglib-2.0.so.0 + 0x44e71) #5 0x00007f470c03946f start_thread (libpthread.so.0 + 0x946f) #6 0x00007f470d0423d3 __clone (libc.so.6 + 0xff3d3) Stack trace of thread 22552: #0 0x00007f470d037abf __poll (libc.so.6 + 0xf4abf) #1 0x00007f470c26163b n/a (libxcb.so.1 + 0xc63b) #2 0x00007f470c26337b xcb_wait_for_event (libxcb.so.1 + 0xe37b) #3 0x00007f470755de01 n/a (libQt5XcbQpa.so.5 + 0x65e01) #4 0x00007f470d3d7dd6 n/a (libQt5Core.so.5 + 0xc9dd6) #5 0x00007f470c03946f start_thread (libpthread.so.0 + 0x946f) #6 0x00007f470d0423d3 __clone (libc.so.6 + 0xff3d3) ----- And here is the stack trace for the second crash: Process 22551 (kalarm) of user 1000 dumped core. Stack trace of thread 23173: #0 0x00007f470cf7ece5 raise (libc.so.6 + 0x3bce5) #1 0x00007f470eda6bf0 _ZN6KCrash19defaultCrashHandlerEi (libKF5Crash.so.5 + 0x4bf0) #2 0x00007f470cf7ed70 __restore_rt (libc.so.6 + 0x3bd70) #3 0x00007f470cf7ece5 raise (libc.so.6 + 0x3bce5) #4 0x00007f470cf68857 abort (libc.so.6 + 0x25857) #5 0x00007f470cf68727 __assert_fail_base.cold (libc.so.6 + 0x25727) #6 0x00007f470cf77426 __assert_fail (libc.so.6 + 0x34426) #7 0x00007f470c03ba46 __pthread_mutex_lock_full (libpthread.so.0 + 0xba46) #8 0x00007f470af69dff pa_mutex_lock (libpulsecommon-13.0.so + 0x2ddff) #9 0x00007f470cb79c20 n/a (libpulse.so.0 + 0xdc20) #10 0x00007f470cb87059 pa_mainloop_poll (libpulse.so.0 + 0x1b059) #11 0x00007f470cb91301 pa_mainloop_iterate (libpulse.so.0 + 0x25301) #12 0x00007f470cb913b1 pa_mainloop_run (libpulse.so.0 + 0x253b1) #13 0x00007f470cb8161e n/a (libpulse.so.0 + 0x1561e) #14 0x00007f470af59d1c n/a (libpulsecommon-13.0.so + 0x1dd1c) #15 0x00007f470c03946f start_thread (libpthread.so.0 + 0x946f) #16 0x00007f470d0423d3 __clone (libc.so.6 + 0xff3d3) Stack trace of thread 22551: #0 0x00007f470c03fcf5 pthread_cond_wait@@GLIBC_2.3.2 (libpthread.so.0 + 0xfcf5) #1 0x00007f470c261819 n/a (libxcb.so.1 + 0xc819) #2 0x00007f470c26308f n/a (libxcb.so.1 + 0xe08f) #3 0x00007f470c2631a2 xcb_wait_for_reply (libxcb.so.1 + 0xe1a2) #4 0x00007f470753354c _ZN14QXcbConnection4syncEv (libQt5XcbQpa.so.5 + 0x3b54c) #5 0x00007f470754edfc n/a (libQt5XcbQpa.so.5 + 0x56dfc) #6 0x00007f470754f100 n/a (libQt5XcbQpa.so.5 + 0x57100) #7 0x00007f470dca7755 _ZN13QBackingStore10beginPaintERK7QRegion (libQt5Gui.so.5 + 0x2f5755) #8 0x00007f470e1cc409 n/a (libQt5Widgets.so.5 + 0x16e409) #9 0x00007f470e1ccfe4 n/a (libQt5Widgets.so.5 + 0x16efe4) #10 0x00007f470e1f6d27 _ZN14QWidgetPrivate16syncBackingStoreEv (libQt5Widgets.so.5 + 0x198d27) #11 0x00007f470e1fdd14 _ZN7QWidget5eventEP6QEvent (libQt5Widgets.so.5 + 0x19fd14) #12 0x00007f470e1b9352 _ZN19QApplicationPrivate13notify_helperEP7QObjectP6QEvent (libQt5Widgets.so.5 + 0x15b352) #13 0x00007f470e1c2829 _ZN12QApplication6notifyEP7QObjectP6QEvent (libQt5Widgets.so.5 + 0x164829) #14 0x00007f470d5b34f2 _ZN16QCoreApplication15notifyInternal2EP7QObjectP6QEvent (libQt5Core.so.5 + 0x2a54f2) #15 0x00007f470d5b5d56 _ZN23QCoreApplicationPrivate16sendPostedEventsEP7QObjectiP11QThreadData (libQt5Core.so.5 + 0x2a7d56) #16 0x00007f470d60c244 n/a (libQt5Core.so.5 + 0x2fe244) #17 0x00007f470b2ae9be g_main_context_dispatch (libglib-2.0.so.0 + 0x6b9be) #18 0x00007f470b2b0831 n/a (libglib-2.0.so.0 + 0x6d831) #19 0x00007f470b2b0871 g_main_context_iteration (libglib-2.0.so.0 + 0x6d871) #20 0x00007f470d60b890 _ZN20QEventDispatcherGlib13processEventsE6QFlagsIN10QEventLoop17ProcessEventsFlagEE (libQt5Core.so.5 + 0x2fd890) #21 0x00007f470d5b205c _ZN10QEventLoop4execE6QFlagsINS_17ProcessEventsFlagEE (libQt5Core.so.5 + 0x2a405c) #22 0x00007f470e3c77de _ZN7QDialog4execEv (libQt5Widgets.so.5 + 0x3697de) #23 0x0000562d31849364 n/a (kalarm + 0x160364) #24 0x0000562d31858410 n/a (kalarm + 0x16f410) #25 0x00007f470e42f708 n/a (libQt5Widgets.so.5 + 0x3d1708) #26 0x00007f470e4353e7 _ZN17QAbstractItemView4editERK11QModelIndexNS_11EditTriggerEP6QEvent (libQt5Widgets.so.5 + 0x3d73e7) #27 0x00007f470e4a88d4 _ZN9QTreeView21mouseDoubleClickEventEP11QMouseEvent (libQt5Widgets.so.5 + 0x44a8d4) #28 0x00007f470e1fd8b9 _ZN7QWidget5eventEP6QEvent (libQt5Widgets.so.5 + 0x19f8b9) #29 0x00007f470e2aecbf _ZN6QFrame5eventEP6QEvent (libQt5Widgets.so.5 + 0x250cbf) #30 0x00007f470e439d70 _ZN17QAbstractItemView13viewportEventEP6QEvent (libQt5Widgets.so.5 + 0x3dbd70) #31 0x00007f470e4aac7c _ZN9QTreeView13viewportEventEP6QEvent (libQt5Widgets.so.5 + 0x44cc7c) #32 0x0000562d3185892d n/a (kalarm + 0x16f92d) #33 0x00007f470d5b3203 _ZN23QCoreApplicationPrivate29sendThroughObjectEventFiltersEP7QObjectP6QEvent (libQt5Core.so.5 + 0x2a5203) #34 0x00007f470e1b9341 _ZN19QApplicationPrivate13notify_helperEP7QObjectP6QEvent (libQt5Widgets.so.5 + 0x15b341) #35 0x00007f470e1c2a78 _ZN12QApplication6notifyEP7QObjectP6QEvent (libQt5Widgets.so.5 + 0x164a78) #36 0x00007f470d5b34f2 _ZN16QCoreApplication15notifyInternal2EP7QObjectP6QEvent (libQt5Core.so.5 + 0x2a54f2) #37 0x00007f470e1c1aeb _ZN19QApplicationPrivate14sendMouseEventEP7QWidgetP11QMouseEventS1_S1_PS1_R8QPointerIS0_Ebb (libQt5Widgets.so.5 + 0x163aeb) #38 0x00007f470e218b21 n/a (libQt5Widgets.so.5 + 0x1bab21) #39 0x00007f470e21baa4 n/a (libQt5Widgets.so.5 + 0x1bdaa4) #40 0x00007f470e1b9352 _ZN19QApplicationPrivate13notify_helperEP7QObjectP6QEvent (libQt5Widgets.so.5 + 0x15b352) #41 0x00007f470e1c2829 _ZN12QApplication6notifyEP7QObjectP6QEvent (libQt5Widgets.so.5 + 0x164829) #42 0x00007f470d5b34f2 _ZN16QCoreApplication15notifyInternal2EP7QObjectP6QEvent (libQt5Core.so.5 + 0x2a54f2) #43 0x00007f470dae61f5 _ZN22QGuiApplicationPrivate17processMouseEventEPN29QWindowSystemInterfacePrivate10MouseEventE (libQt5Gui.so.5 + 0x1341f5) #44 0x00007f470dae79b6 _ZN22QGuiApplicationPrivate24processWindowSystemEventEPN29QWindowSystemInterfacePrivate17WindowSystemEventE (libQt5Gui.so.5 + 0x1359b6) #45 0x00007f470dabfc5c _ZN22QWindowSystemInterface22sendWindowSystemEventsE6QFlagsIN10QEventLoop17ProcessEventsFlagEE (libQt5Gui.so.5 + 0x10dc5c) #46 0x00007f470755ee2c n/a (libQt5XcbQpa.so.5 + 0x66e2c) #47 0x00007f470b2ae9be g_main_context_dispatch (libglib-2.0.so.0 + 0x6b9be) #48 0x00007f470b2b0831 n/a (libglib-2.0.so.0 + 0x6d831) #49 0x00007f470b2b0871 g_main_context_iteration (libglib-2.0.so.0 + 0x6d871) #50 0x00007f470d60b890 _ZN20QEventDispatcherGlib13processEventsE6QFlagsIN10QEventLoop17ProcessEventsFlagEE (libQt5Core.so.5 + 0x2fd890) #51 0x00007f470d5b205c _ZN10QEventLoop4execE6QFlagsINS_17ProcessEventsFlagEE (libQt5Core.so.5 + 0x2a405c) #52 0x00007f470d5ba066 _ZN16QCoreApplication4execEv (libQt5Core.so.5 + 0x2ac066) #53 0x0000562d317773bd n/a (kalarm + 0x8e3bd) #54 0x00007f470cf6a023 __libc_start_main (libc.so.6 + 0x27023) #55 0x0000562d31777d2e n/a (kalarm + 0x8ed2e) Stack trace of thread 22553: #0 0x00007f470b2affc4 g_main_context_prepare (libglib-2.0.so.0 + 0x6cfc4) #1 0x00007f470b2b06c6 n/a (libglib-2.0.so.0 + 0x6d6c6) #2 0x00007f470b2b0871 g_main_context_iteration (libglib-2.0.so.0 + 0x6d871) #3 0x00007f470d60b8ac _ZN20QEventDispatcherGlib13processEventsE6QFlagsIN10QEventLoop17ProcessEventsFlagEE (libQt5Core.so.5 + 0x2fd8ac) #4 0x00007f470d5b205c _ZN10QEventLoop4execE6QFlagsINS_17ProcessEventsFlagEE (libQt5Core.so.5 + 0x2a405c) #5 0x00007f470d3d6c62 _ZN7QThread4execEv (libQt5Core.so.5 + 0xc8c62) #6 0x00007f470d906b28 n/a (libQt5DBus.so.5 + 0x15b28) #7 0x00007f470d3d7dd6 n/a (libQt5Core.so.5 + 0xc9dd6) #8 0x00007f470c03946f start_thread (libpthread.so.0 + 0x946f) #9 0x00007f470d0423d3 __clone (libc.so.6 + 0xff3d3) Stack trace of thread 22554: #0 0x00007f470cfc89d3 __libc_enable_asynccancel (libc.so.6 + 0x859d3) #1 0x00007f470d037aa7 __poll (libc.so.6 + 0xf4aa7) #2 0x00007f470b2b07a0 n/a (libglib-2.0.so.0 + 0x6d7a0) #3 0x00007f470b2b0871 g_main_context_iteration (libglib-2.0.so.0 + 0x6d871) #4 0x00007f470d60b8ac _ZN20QEventDispatcherGlib13processEventsE6QFlagsIN10QEventLoop17ProcessEventsFlagEE (libQt5Core.so.5 + 0x2fd8ac) #5 0x00007f470d5b205c _ZN10QEventLoop4execE6QFlagsINS_17ProcessEventsFlagEE (libQt5Core.so.5 + 0x2a405c) #6 0x00007f470d3d6c62 _ZN7QThread4execEv (libQt5Core.so.5 + 0xc8c62) #7 0x00007f470d3d7dd6 n/a (libQt5Core.so.5 + 0xc9dd6) #8 0x00007f470c03946f start_thread (libpthread.so.0 + 0x946f) #9 0x00007f470d0423d3 __clone (libc.so.6 + 0xff3d3) Stack trace of thread 23174: #0 0x00007f470d03cf8d syscall (libc.so.6 + 0xf9f8d) #1 0x00007f470b25f531 g_cond_wait (libglib-2.0.so.0 + 0x1c531) #2 0x00007f46f4b89603 n/a (libgstreamer-1.0.so.0 + 0x4b603) #3 0x00007f470b2854e7 n/a (libglib-2.0.so.0 + 0x424e7) #4 0x00007f470b287e71 n/a (libglib-2.0.so.0 + 0x44e71) #5 0x00007f470c03946f start_thread (libpthread.so.0 + 0x946f) #6 0x00007f470d0423d3 __clone (libc.so.6 + 0xff3d3) Stack trace of thread 23170: #0 0x00007f470d03cf8d syscall (libc.so.6 + 0xf9f8d) #1 0x00007f470b25f531 g_cond_wait (libglib-2.0.so.0 + 0x1c531) #2 0x00007f46f4b89603 n/a (libgstreamer-1.0.so.0 + 0x4b603) #3 0x00007f470b2854e7 n/a (libglib-2.0.so.0 + 0x424e7) #4 0x00007f470b287e71 n/a (libglib-2.0.so.0 + 0x44e71) #5 0x00007f470c03946f start_thread (libpthread.so.0 + 0x946f) #6 0x00007f470d0423d3 __clone (libc.so.6 + 0xff3d3) Stack trace of thread 23175: #0 0x00007f470d03cf8d syscall (libc.so.6 + 0xf9f8d) #1 0x00007f470b25f531 g_cond_wait (libglib-2.0.so.0 + 0x1c531) #2 0x00007f46f4b89603 n/a (libgstreamer-1.0.so.0 + 0x4b603) #3 0x00007f470b2854e7 n/a (libglib-2.0.so.0 + 0x424e7) #4 0x00007f470b287e71 n/a (libglib-2.0.so.0 + 0x44e71) #5 0x00007f470c03946f start_thread (libpthread.so.0 + 0x946f) #6 0x00007f470d0423d3 __clone (libc.so.6 + 0xff3d3) Stack trace of thread 22552: #0 0x00007f470d037abf __poll (libc.so.6 + 0xf4abf) #1 0x00007f470c26163b n/a (libxcb.so.1 + 0xc63b) #2 0x00007f470c26337b xcb_wait_for_event (libxcb.so.1 + 0xe37b) #3 0x00007f470755de01 n/a (libQt5XcbQpa.so.5 + 0x65e01) #4 0x00007f470d3d7dd6 n/a (libQt5Core.so.5 + 0xc9dd6) #5 0x00007f470c03946f start_thread (libpthread.so.0 + 0x946f) #6 0x00007f470d0423d3 __clone (libc.so.6 + 0xff3d3)
This seems to be a crash in the PulseAudio library. The thread which crashed doesn't have any kalarm or KDE Frameworks calls, which indicates that kalarm's commands to play the sound have been processed and accepted first by the Phonon audio library and then passed successfully to PulseAudio (looking at the other threads, apparently via libgstreamer). Once it has got that far, it must be a bug in PulseAudio which has caused the crash. If kalarm was doing something wrong, the libraries being called should have noticed and rejected the commands, rather than passing them on for execution.