b3b2e61c19
The order in which the argument list is evaluated is unspecified, so it was possible for g_steal_pointer to set self = NULL before self->old_governor was evaluated, resulting in a crash: Program terminated with signal SIGSEGV, Segmentation fault. #0 0x00007f6efc678d84 in enable_paranoid_cb (object=0x561a4d147c80, result=0x561a4d173560, user_data=0x561a4d09d610) at ../src/libsysprof/sysprof-governor-source.c:290 290 self->old_governor, [Current thread is 1 (Thread 0x7f6efae4b600 (LWP 122786))] (gdb) bt #0 0x00007f6efc678d84 in enable_paranoid_cb (object=0x561a4d147c80 [SysprofHelpers], result=0x561a4d173560, user_data=0x561a4d09d610) at ../src/libsysprof/sysprof-governor-source.c:290 #1 0x00007f6efd51b389 in g_task_return_now (task=0x561a4d173560 [GTask]) at ../../../gio/gtask.c:1219 #2 0x00007f6efd51becb in g_task_return (type=<optimized out>, task=0x561a4d173560 [GTask]) at ../../../gio/gtask.c:1289 #3 g_task_return (task=0x561a4d173560 [GTask], type=<optimized out>) at ../../../gio/gtask.c:1245 #4 0x00007f6efc6a6060 in sysprof_helpers_set_paranoid_cb (object=0x561a4cf9df90 [IpcServiceProxy], result=0x561a4d1736e0, user_data=0x561a4d173560) at ../src/libsysprof/sysprof-helpers.c:788 #5 0x00007f6efd51b389 in g_task_return_now (task=0x561a4d1736e0 [GTask]) at ../../../gio/gtask.c:1219 #6 0x00007f6efd51becb in g_task_return (type=<optimized out>, task=0x561a4d1736e0 [GTask]) at ../../../gio/gtask.c:1289 #7 g_task_return (task=0x561a4d1736e0 [GTask], type=<optimized out>) at ../../../gio/gtask.c:1245 #8 0x00007f6efd5830cb in reply_cb (connection=<optimized out>, res=<optimized out>, user_data=user_data@entry=0x561a4d1736e0) at ../../../gio/gdbusproxy.c:2568 #9 0x00007f6efd51b389 in g_task_return_now (task=0x561a4d22b000 [GTask]) at ../../../gio/gtask.c:1219 #10 0x00007f6efd51becb in g_task_return (type=<optimized out>, task=0x561a4d22b000 [GTask]) at ../../../gio/gtask.c:1289 #11 g_task_return (task=0x561a4d22b000 [GTask], type=<optimized out>) at ../../../gio/gtask.c:1245 #12 0x00007f6efd577cbf in g_dbus_connection_call_done (source=<optimized out>, result=0x561a4d22b0c0, user_data=user_data@entry=0x561a4d22b000) at ../../../gio/gdbusconnection.c:5797 #13 0x00007f6efd51b389 in g_task_return_now (task=0x561a4d22b0c0 [GTask]) at ../../../gio/gtask.c:1219 #14 0x00007f6efd51b3c9 in complete_in_idle_cb (task=0x561a4d22b0c0) at ../../../gio/gtask.c:1233 #15 0x00007f6efd32db84 in g_main_dispatch (context=0x561a4cb60af0) at ../../../glib/gmain.c:3381 #16 g_main_context_dispatch (context=0x561a4cb60af0) at ../../../glib/gmain.c:4099 #17 0x00007f6efd32df28 in g_main_context_iterate (context=context@entry=0x561a4cb60af0, block=block@entry=1, dispatch=dispatch@entry=1, self=<optimized out>) at ../../../glib/gmain.c:4175 #18 0x00007f6efd32dfdf in g_main_context_iteration (context=context@entry=0x561a4cb60af0, may_block=may_block@entry=1) at ../../../glib/gmain.c:4240 #19 0x00007f6efd54a06d in g_application_run (application=0x561a4cb56120 [SysprofApplication], argc=<optimized out>, argv=<optimized out>) at ../../../gio/gapplication.c:2569 #20 0x0000561a4b2edd14 in main (argc=1, argv=0x7ffddcebb708) at ../src/sysprof/sysprof.c:44 (gdb) info locals helpers = 0x561a4d147c80 [SysprofHelpers] self = 0x0 error = 0x0 old_governor = -1 __func__ = "enable_paranoid_cb"
Sysprof is a sampling profiler that uses a kernel module to generate stacktraces which are then interpreted by the userspace program "sysprof".
See the Sysprof homepage for more information.
Merge requests and bug reports should be sent to sysprof's repository on GNOME's GitLab instance. For general discussion and questions, you can create a new topic in GNOME's Discourse.
The former mailing list is archived in https://mail.gnome.org/archives/sysprof-list/.
Debugging symbols
The programs and libraries you want to profile should be compiled
with -fno-omit-frame-pointer and have debugging symbols available,
or you won't get much usable information.
Building Sysprof
You need some packages installed. The package names may vary depending on your distribution, the following command works on Fedora 25:
sudo dnf install gcc gcc-c++ ninja-build gtk3-devel
Then do the following:
meson --prefix=/usr build
cd build
ninja
sudo ninja install
WARNING: ninja install will mostly install under the configured install
prefix but installs systemd service configuration directly in the system
default location /usr/lib/systemd so it won't work without root privileges,
even if the install prefix is a user-owned directory.