Re: Erratic ping behavior, was Re: Pi3 answers ssh only if outbound ping is running on -current

From: Mark Millard <marklmi_at_yahoo.com>
Date: Sun, 13 Mar 2022 22:00:24 UTC
[The USB I/O problem.]

On 2022-Mar-13, at 13:46, Mark Millard <marklmi@yahoo.com> wrote:

>> FreeBSD pelorus.zefox.org 13.1-STABLE FreeBSD 13.1-STABLE #24 stable/13-n249989-b85d0d603c5: Sat Mar 12 17:47:19 PST 2022    bob@pelorus.zefox.org:/usr/obj/usr/src/arm64.aarch64/sys/GENERIC arm64
> 
>> . . .
>> 
>> Unfortunately, new console errors are appeared:
>> 
>> bob@pelorus:~ % (da0:umass-sim0:0:0:0): WRITE(10). CDB: 2a 00 1f ea a3 c0 00 00 40 00 
>> (da0:umass-sim0:0:0:0): CAM status: SCSI Status Error
>> (da0:umass-sim0:0:0:0): SCSI status: Check Condition
>> (da0:umass-sim0:0:0:0): SCSI sense: ABORTED COMMAND asc:47,3 (Information unit iuCRC error detected)
>> (da0:umass-sim0:0:0:0): Retrying command (per sense data)

Quoting part of a forum reply:

QUOTE
That error translates to "INFORMATION UNIT iuCRC ERROR DETECTED" (cut and pasted from the SCSI standard), which means an error in data transmission between the disk and the controller, not an error on the disk.
END QUOTE

You report: stable/13-n249989-b85d0d603c5 shows the problem and
later that 13-n249985-dd6c1475a63 does not. That is odd because
the only stable/13 activity after dd6c1475a63 is (newer to older):

git: b85d0d603c57 - stable/13 - tslog.4: Document TSLOG Mateusz Piotrowski 
git: 85379a47c4cb - stable/13 - time.3: Update ERRORS section Mateusz Piotrowski 
git: 991c0e3ddb93 - stable/13 - ctime.3: Add a cross-reference to clock_gettime(2) Mateusz Piotrowski 
git: bd2e56ef47d5 - stable/13 - zfs: merge openzfs/zfs_at_ef83e07db (zfs-2.1-release) into stable/13 Martin Matuska 

In other words: updates to man pages and a zfs update.
As I understand, you do not use zfs.

The next commit back is the dd6c1475a63 that you report as working:

git: dd6c1475a63a - stable/13 - Add support for getting early entropy from UEFI Colin Percival 

A possibility might be a poor connection that was later
reconnected (with better contact)? Brownout power
conditions?

It seems odd for zfs to be involved but man page changes
have no chance of being involved. It tends to suggest a
non-software issue at the time.

> . . .
> 
>> The error message repeated at intervals, seemingly linked to disk activity,
>> with the machine running out of retries after starting buildworld. 
>> That seems like progress in reverse 8-)
> 
> So you have bounds for a bisect to find where the USB
> failures start happening on your RPi3, if you want to
> investigate that.

Looks like this idea was a bust, given the narrow range
and the content involved in that range.

>> Reverting to 13-n249985-dd6c1475a63: Fri Mar 11 18:06:31 PST 2022
>> permitted recovery, with the old problems attendant.
>> 
>> -current now has some usb testing tools:
>> root@www:/usr/src # ls tools/tools/usbtest
>> Makefile		usb_control_ep_test.c	usb_msc_test.c		usbtest.c
>> Makefile.depend		usb_modem_test.c	usb_msc_test.h		usbtest.h
>> 
>> Is there any guidance on what they do? I couldn't find a man page.
>> 
> 
> 



===
Mark Millard
marklmi at yahoo.com