RPI2 boot hangs with red light on

[Mark Millard]

On 2018-Jan-3, at 9:42 PM, bob prohaska <fbsd at www.zefox.net> wrote:

> On Wed, Jan 03, 2018 at 09:21:29PM -0700, Ian Lepore wrote:
> . . .
> 
> It looks as if /boot/kernel loads but won't run, and /boot/kernel.spare, which
> formerly ran, no longer does. Curiously, an intermediate kernel, which didn't
> run, now loads and starts but halts with
> 
> ugen0.8: <vendor 0x067b product 0x2303> at usbus0
> da0 at umass-sim0 bus 0 scbus0 target 0 lun 0
> da0: <SanDisk Extreme 0001> Removable Direct Access SPC-4 SCSI device
> da0: Serial Number AA010509160727180727
> da0: 40.000MB/s transfers
> da0: 59836MB (122544516 512 byte sectors)
> da0: quirks=0x2<NO_6_BYTE>
> Release APs
> WARNING: WITNESS option enabled, expect reduced performance.
> random: unblocking device.
> arc4random: no preloaded entropy cache
> Trying to mount root from ufs:/dev/ufs/rootfs [rw]...
> arc4random: no preloaded entropy cache
> arc4random: no preloaded entropy cache

I've seen this "hang point" on a Pine64+ 2GB
in the past.

Hanging here is something addressed by the
"UMA limit" part of head -r327485 . Bugzilla
224330 has material about it. As I understand
-r326347 is what broke that specific aspect
of things. (It had other issues as well,
and apparently causes some other problem to
show up that was previous hidden.)

As for -r327485:

Author: jeff
Date: Tue Jan  2 04:35:56 2018
New Revision: 327485
URL: 
https://svnweb.freebsd.org/changeset/base/327485


Log:
  Fix arc after r326347 broke various memory limit queries.  Use UMA features
  rather than kmem arena size to determine available memory.
  
  Initialize the UMA limit to LONG_MAX to avoid spurious wakeups on boot before
  the real limit is set.
  
  PR:		224330 (partial), 224080
  Reviewed by:	markj, avg
  Sponsored by:	Netflix / Dell EMC Isilon
  Differential Revision:	
https://reviews.freebsd.org/D13494
. . .


The "arc" reference is a ZFS file system handling issue.



Note: I've no clue for "Timeout poll on interrupt endpoint".
I've never seen such before.

===
Mark Millard
markmi at dsl-only.net