Spontaneous reboot after ACPI shutdown

[andrew morton]

I've been experiencing a strange problem and was wondering if anyone
else had encountered it. I'm running 5.1-CURRENT (as of about two weeks
ago) on an IBM A21e Thinkpad. For the most part ACPI seems to be working
pretty well. 

When I shutdown the computer it powers off correctly and everything
seems okay but about 5-10 minutes later it just turns itself back on. If
the lid is shut the laptop assumes it's in docked mode and ignores the
built-in keyboard and display forcing me to do a hard reset (if I've
noticed it before the battery dies) and wait through the fsck. 

The workaround is to just power up after the shutdown let it load the 
boot manager and then power back down. Has anyone else seen this? Is
there a fix?

andrew