* Mathieu Desnoyers ([email protected]) wrote: > * Bernd Hufmann ([email protected]) wrote: [...] > > Steps to reproduce: > > - Enable all markers (use ltt-armall) > > - Start tcf-client > > - connect <remote> > > - tcf ltt_control setupTrace "kernel" "0" "h2" > > - tcf ltt_control setChannelEnable "kernel" "0" "h2" false > > - tcf ltt_control allocTrace "kernel" "0" "h2" > > - lttctl_client ltt_control writeTraceLocal "kernel" "0" "h2" > > "/tmp/h2" 2 false false false > > - tcf ltt_control startTrace "kernel" "0" "h2" > > > > Now, the command startTrace won't return. It hangs on line "if > > (write(fd, op, strlen(op)) == -1)" of method "lttctl_sendop()" which was > > called by method "lttctl_start()" (see file liblttctrl.c). Please see > > attached file "dmesg_start.log" for the dmesg output. > > > [...] > > [ 416.740678] LTT : Tracing not active for trace h5 > > [ 416.740908] LTT state dump begin > > [ 416.740931] LTT state dump thread start > > [ 416.743693] LTT state dump end > > [ 447.956279] LTT: 36 events written in channel metadata (cpu 0, index 0) > > [ 447.956424] LTT: 54278 events written in channel fs (cpu 0, index 0) > > [ 447.956468] LTT: 40989 events written in channel fs (cpu 0, index 1) > > [ 618.382904] LTT : Tracing not active for trace h6 > > [ 618.383350] BUG: unable to handle kernel NULL pointer dereference at > > 00000014 > > [ 618.383983] IP: [<e080828f>] ltt_trace_start+0x7f/0x190 [ltt_tracer] > > This looks like a bug in lttng-modules (the LTTng kernel modules). > Probably a bug with the way the current LTTng-stable versions handle the > trace session "templates". The good news is that we are getting rid of > all that code in the upcoming LTTng (with UST/ltt-sessiond/CTF > integration), so this bug is very likely to vanish then. > > I'll try to have a look. > > Thanks for reporting this.
It should be fixed in the lttng-modules.git tree v0.19-stable branch now (commit e5b34c668a7d7b8aeab9fa2bdbb31eed4eff7929). Can you try again using this version of lttng-modules and confirm that it fixes your crash before I post a new lttng-modules v0.19-stable release ? Thanks, Mathieu -- Mathieu Desnoyers Operating System Efficiency R&D Consultant EfficiOS Inc. http://www.efficios.com _______________________________________________ ltt-dev mailing list [email protected] http://lists.casi.polymtl.ca/cgi-bin/mailman/listinfo/ltt-dev
