Documentation/power/basic-pm-debugging.rst

10 To check if hibernation works, you can try to hibernate in the "reboot" mode::
15 and the system should create a hibernation image, reboot, resume and get back to
20 resuming the system.]  Moreover, hibernating in the "reboot" and "shutdown"
21 modes causes the PM core to skip some platform-related callbacks which on ACPI
39 button to make the system resume).
45 ----------------------------
47 To find out why hibernation fails on your system, you can use a special testing
53 	- test the freezing of processes
56 	- test the freezing of processes and suspending of devices
59 	- test the freezing of processes, suspending of devices and platform
63 	- test the freezing of processes, suspending of devices, platform
67 	- test the freezing of processes, suspending of devices, platform global
69 	  of platform/system devices
97 contains a space-separated list of all available tests (including "none" that
116 or resume its device (in the latter case the system may hang or become unstable
120 - if the test fails, unload a half of the drivers currently loaded and repeat
121   (that would probably involve rebooting the system, so always note what drivers
123 - if the test succeeds, load a half of the drivers you have unloaded most
137 platform (eg. ACPI) firmware on your system.  In that case the "platform" mode
144 off and on using the /sys/devices/system/cpu/cpu*/online sysfs attributes and
147 If the "core" test fails, which means that suspending of the system/platform
149 the problem is most probably hardware-related and serious, so it should be
153 system to hang or become unstable, so please beware.  Such a failure usually
158 --------------------------------
160 If all of the hibernation test modes work, you can boot the system with the
168 - if there are n modules loaded and the attempt to suspend and resume fails,
170 the system),
171 - if there are n modules loaded and the attempt to suspend and resume succeeds,
178 ---------------------------------------------
191 That test can be used to check if failures to resume from hibernation are
199 kernel address space randomization, it also can be used to check if failures
204 ---------------------
206 In case that hibernation does not work on your system even in the minimal
222 http://en.opensuse.org/SDB:Suspend_to_RAM (S2RAM_LINK).
230 invocation of the platform firmware in order to put the system into the sleep
237 Next, you can follow the instructions at S2RAM_LINK to test the system, but if
248 	# mount -t debugfs none /sys/kernel/debug
261 	  last_failed_errno:	-16
262 				-16