ThinkPad: reboots after successful shutdown -p

[Unbound]

On 2021-03-17 00:01, Xin Li via freebsd-current wrote:
> On 3/16/21 9:45 PM, Warner Losh wrote:
>> 
>> 
>> On Tue, Mar 16, 2021 at 10:18 PM Xin Li <delphij at freebsd.org
>> <mailto:delphij at freebsd.org>> wrote:
>> 
>>     On 11/17/19 23:14, Xin Li wrote:
>>     > Hi,
>>     >
>>     > I recently noticed that if I do a 'shutdown -p' from -CURRENT, the
>>     > system would shut down and seemingly powered off, then it would
>>     restart
>>     > after about 5-10 seconds.
>>     >
>>     > Is this a known issue?  Arguably this is not necessarily a FreeBSD
>>     > issue, but it seems that the Windows 10 installation doesn't have the
>>     > problem, so I guess there might be some difference between our and
>>     > Windows's shutdown sequence.
>> 
>>     I've found a workaround for this, for the record, setting
>>     hw.efi.poweroff=0 would make the laptop to correctly shutdown.
>> 
>>     However I don't see anything wrong with sys/dev/efidev/efirt.c's
>>     implementation of EFI shutdown; it appears to be essentially the same 
>> as
>>     implemented in command_poweroff() in stand/efi/loader/main.c, but
>>     'poweroff' would work just fine in loader.efi.
>> 
>>     Can someone familiar with the code shed me some light here? :-)
>> 
>>     It looks like what Linux did was to prefer ACPI S5, unless it's not
>>     available or the system have HW_REDUCED flag in FADT, so if we do
>>     something similar it would fix the issue for me, but according to
>>     bugs.freebsd.org/233998 <http://bugs.freebsd.org/233998> that's not
>>     the case for at least Conor's system
>>     (_S5 appears to be in the ACPI dump), so I think it's something else...
>> 
>> 
>> For me, interrupt storm on shutdown has been the causes of issues like
>> this...
>> 
>> Any chance you can eliminate that as a possibility?
> 
> Hmm, that's a good question -- is there a way to tell after the screen
> was turned off?
> 
> Before the screen was turned off, there doesn't appear to be interrupt
> storm.  The system was performing a typical FreeBSD shutdown procedure:
> All buffers synced, showed uptime, destroyed GELI devices, spin down the
> SATA devices, shutdown the cardreader (rtsx0), detached all USB devices
> (hidraw1, hidbus, usbhid1, ubt0, uhub0), screen turned slightly red for
> a very brief period (maybe side effect of turning off the backlight),
> then goes off.
> 
> I think most of FreeBSD drivers would turn off interrupt from the device
> before detaching, but I haven't looked into all of my devices; but from
> what I have seen on screen (captured a 60fps video and can share if that
> helps), there doesn't appear to be an interrupt storm before that.
> 
> Cheers,
FWIW this also happened to me a few weeks ago after a fresh install.
I've since wiped the disk and repurposed the hardware. So I can't now
reproduce it. But it wasn't a laptop. So it's not isolated to them.
Sorry I can't offer anything more. I just wanted to mention this to
indicate that it's not a _too_ terribly isolated case. It was Intel
CPU/graphics. In case that says anything to anyone. If it matters,
I can get/offer more info on the hardware.

--Chris