Lost my serial console! :-)

Thu Nov 22 16:31:17 UTC 2018

On 2018-Nov-22, at 08:14, Mark Millard <marklmi at yahoo.com> wrote:

> On 2018-Nov-22, at 03:27, Karl Denninger <karl at denninger.net> wrote:
> 
>> On 11/21/2018 17:03, Rodney W. Grimes wrote:
>>>> On 11/20/2018 09:57, Rodney W. Grimes wrote:
>>>> .....
>>>>>> Lots.? I have several 3Bs, one 3B+ (since that's the current model), and
>>>>>> a passel of 2s. :-)? The 2s are fine but I'm building 11.STABLE for
>>>>>> those.? Can't for the 3s, as the code to run those isn't in 11.
>>>>> Ok which of PI3B or PI3B+ or is it both that you are having
>>>>> serial console issues on?
>>>>> 
>>>>> Also can you try:
>>>>> 	http://ftp.freebsd.org/pub/FreeBSD/releases/ISO-IMAGES/12.0/FreeBSD-12.0-RC1-arm64-aarch64-RPI3.img.xz
>>>>> on both boards and report success/failure/problems?
>>>>> 
>>>>> Thanks,
>>>> RC1 boots on both and I have a serial console on both.?
>>> Thank you for the testing, I am ccing this reply to RE@ so they
>>> know we have at least 1 data point that says we can boot our
>>> release canadate image on both a RPI3B and RPI3B+,
>>> that is valuable data.
>> One note -- there is a complaint about umodem.ko missing dependencies
>> right at the top of the kernel messages on boot and indeed it does not
>> load out of the loader.conf entry -- but if I load it by hand once the
>> system is up (or out of /etc/rc.local, etc) it works.  So while it does
>> indeed boot I wouldn't call it completely "working" (at least not if you
>> need the umodem kernel module!)
>> 
>> This happens to impact me on these devices (I have a USB device that
>> "appears" as a serial modem).... it's been broken for a while on
>> -CURRENT, but I don't know exactly *when* it broke.  On the Pi2 under
>> 11-Stable it hasn't been a problem.
> 
> Looking on the web I see an example from -r335317 :
> 
> FreeBSD 12.0-CURRENT #0 r335317: Mon Jun 18 17:37:04 UTC 2018
>    root at releng3.nyi.freebsd.org:/usr/obj/usr/src/arm64.aarch64/sys/GENERIC arm64
> FreeBSD clang version 6.0.0 (tags/RELEASE_600/final 326565) (based on LLVM 6.0.0)
> WARNING: WITNESS option enabled, expect reduced performance.
> VT: init without driver.
> KLD file umodem.ko is missing dependencies
> KLD file if_run.ko is missing dependencies
> 
> But if I remove umodem.ko being the specific
> example there is more --and some notes that
> might provide a workaround . . .
> 
> There are examples around of folks getting the type of message for
> zfs.ko , where the solution was to force /boot/kernel/opensolaris.ko
> to load ahead of time instead of depending on it automatically
> happening. -r317181 was an example, quoting:
> 
> QUOTE
> With a slimmed down kernel config, I can load zfs.ko and boot the kernel 
> BUT opensolaris is not loaded and I get at kernel boot: 
> 
> OK load zfs 
> /boot/kernel/zfs.ko text=0x9d980 text=0xe0480 data=0x214c8+0x9eb78 
> syms=[0x8+0x1d6a0+0x8+0x187bd] 
> OK boot 
> Booting... 
> KDB: debugger backends: ddb 
> KDB: current backend: ddb 
> Copyright (c) 1992-2017 The FreeBSD Project. 
> Copyright (c) 1979, 1980, 1983, 1986, 1988, 1989, 1991, 1992, 1993, 1994 
>         The Regents of the University of California. All rights reserved. 
> FreeBSD is a registered trademark of The FreeBSD Foundation. 
> FreeBSD 12.0-CURRENT #0 r317181M: Sun May 14 14:01:52 CEST 2017 
>     [hidden email]:/usr/obj/usr/src/sys/NORQUAY arm64 
> FreeBSD clang version 4.0.0 (tags/RELEASE_400/final 297347) (based on 
> LLVM 4.0.0) 
> VT: init without driver. 
> KLD file zfs.ko is missing dependencies 
> END QUOTE
> 
> and:
> 
> QUOTE
> If I load opensolaris manually, I can mount My root filesystem from zfs 
> 
> OK load opensolaris 
> /boot/kernel/opensolaris.ko text=0x19d8 text=0xda0 data=0x10178+0x125b8 
> syms=[0x8+0x1020+0x8+0x8ca] 
> OK boot -s 
> Booting... 
> . . .
> END QUOTE
> 
> That does suggest that there may be a workaround of explicitly
> loading the modules that umodem.ko requires instead of depending
> on implicit loading. This is true even if the person needed to
> do a kldxref and at the time it might have worked after that.
> 
> (In the current context having an up to date linker.hints file
> is known to be insufficient. Back then I'm unsure of the
> status. But the procedure may either anyway.)
> 
> The quotes are from:
> 
> http://freebsd.1045724.x6.nabble.com/Re-DTB-provided-by-loader-efi-from-head-r317181-on-pine64-smashed-by-zfs-ko-td6185085.html
> 
> All the examples I'm referring to are arm64 in 2017 or later.
> Over such a range I've not run into a non-arm64 example.
> 
> (I Did find old FreeBSD 9 missing-dependencies reports and
> powerpc reports from years before that range. I ignored these.)

I just tested and:

hw.usb.template=3
# ucom is not automatically being loaded when umodem is loaded at boot.
ucom_load="YES"
umodem_load="YES"

in /boot/loader.conf worked: no more message about umodem.ko
missing dependencies.

It looks like 12.x should have a note about amd64 requiring
such completeness in what is listed in /boot/loader.conf
or what is types at the loader prompts. (Presuming that this
is not fixed before 12.0-RELEASE .)

I greatly doubt that the issue is specific to umodem.ko and
what it requires to also be loaded. (Note the if_run.ko
example that was in materials that I quoted and the
zfs.ko example that suggested the workaround.)

===
Mark Millard
marklmi at yahoo.com
( dsl-only.net went
away in early 2018-Mar)