[Galaxy Tab 10.1 Android Development] forrestgump2000:
Yeah, that seems to be what is happening. When the tablet spontaneously hard reboots, it seems that the last_kmsg is never one from when the system did the hard reboot. For example, after the last spontaneous reboot, I see this:

[ 484.199994] input: [sec_power_key] P

[ 485.410007] input: [sec_power_key] R

[ 490.379562] healthd: battery l=100 v=4026 t=22.2 h=2 st=3 chg= 2016-03-20 14:41:52.863905000 UTC

[ 490.692248] SysRq : Emergency Remount R/O

[ 490.710977] EXT4-fs (mmcblk0p5): re-mounted. Opts: (null)

[ 490.779221] EXT4-fs (mmcblk0p8): re-mounted. Opts: (null)

[ 490.815721] EXT4-fs (mmcblk0p1): re-mounted. Opts: (null)

[ 490.816127] Emergency Remount complete

[ 490.872105] Wake9 for irq=338

[ 490.896456] LINUX_REBOOT_CMD_RESTART2

[ 490.897613] command : boot-reboot written on MISC

[ 490.901392] VFS: Close: file count is 0

[ 491.570478] Board P4 : tegra_usb_ldo_en=1 instance=2 present regulator=0

[ 491.575390] Board P4 : tegra_usb_ldo_en=0 instance=2 present regulator=1

[ 491.575799] Restarting system with command ''.

[ 491.576018] ------------[ cut here ]------------

[ 491.576287] WARNING: at ../../../../../../kernel/samsung/p4/kernel/smp.c:459 smp_call_function_many+0xf8/0x2b8()

[ 491.576548] Modules linked in: dhd

[ 491.576902] [<c0015368>] (unwind_backtrace+0x0/0xf4) from [<c0051f7c>] (warn_slowpath_null+0x3c/0x54)

[ 491.577164] [<c0051f7c>] (warn_slowpath_null+0x3c/0x54) from [<c008a1fc>] (smp_call_function_many+0xf8/0x2b8)

[ 491.577411] [<c008a1fc>] (smp_call_function_many+0xf8/0x2b8) from [<c008a400>] (smp_call_function+0x44/0x74)

[ 491.577648] [<c008a400>] (smp_call_function+0x44/0x74) from [<c008a458>] (on_each_cpu+0x28/0x70)

[ 491.577819] [<c008a458>] (on_each_cpu+0x28/0x70) from [<c0013ff8>] (smp_send_stop+0xc/0xd0)

[ 491.578063] [<c0013ff8>] (smp_send_stop+0xc/0xd0) from [<c000f2fc>] (machine_restart+0x18/0x68)

[ 491.578310] [<c000f2fc>] (machine_restart+0x18/0x68) from [<c0067870>] (sys_reboot+0x224/0x24c)

[ 491.578569] [<c0067870>] (sys_reboot+0x224/0x24c) from [<c000e2c0>] (ret_fast_syscall+0x0/0x30)

[ 491.578732] ---[ end trace 5a0920a47a1a3937 ]---

[ 491.578961] ------------[ cut here ]------------

[ 491.579131] WARNING: at ../../../../../../kernel/samsung/p4/kernel/smp.c:320 smp_call_function_single+0x18c/0x1f8()

[ 491.579376] Modules linked in: dhd

[ 491.579757] [<c0015368>] (unwind_backtrace+0x0/0xf4) from [<c0051f7c>] (warn_slowpath_null+0x3c/0x54)

[ 491.580039] [<c0051f7c>] (warn_slowpath_null+0x3c/0x54) from [<c0089f48>] (smp_call_function_single+0x18c/0x1f8)

[ 491.580282] [<c0089f48>] (smp_call_function_single+0x18c/0x1f8) from [<c008a400>] (smp_call_function+0x44/0x74)

[ 491.580548] [<c008a400>] (smp_call_function+0x44/0x74) from [<c008a458>] (on_each_cpu+0x28/0x70)

[ 491.580799] [<c008a458>] (on_each_cpu+0x28/0x70) from [<c0013ff8>] (smp_send_stop+0xc/0xd0)

[ 491.581054] [<c0013ff8>] (smp_send_stop+0xc/0xd0) from [<c000f2fc>] (machine_restart+0x18/0x68)

[ 491.581245] [<c000f2fc>] (machine_restart+0x18/0x68) from [<c0067870>] (sys_reboot+0x224/0x24c)

[ 491.581496] [<c0067870>] (sys_reboot+0x224/0x24c) from [<c000e2c0>] (ret_fast_syscall+0x0/0x30)

[ 491.581735] ---[ end trace 5a0920a47a1a3938 ]---

So while this is from the Android OS rather than TWRP, it's from when I held in the power button and manually triggered a reboot. This last time that it happened correlated to me rotating the screen. So as well as disabling GPS, I've also turned off screen rotation as well. Though since I've had reboots with either disabled individually, I still get the impression that the hard reboot happens under heavy load, rather than a particular activity. Note that screen rotation on Android is actually a non-trivial activity, as the current process is destroyed and recreated to allow it to re-read the device configuration.