A reliable port cross-build failure (hangup) in my context (amd64->armv7 cross build, with native-tool speedup involved)

[Mark Millard]

[A native poudreire-devel based build of
multimedia/gstreamer1-qt at qt5 did not hang-up
and worked fine. Official package build history
also provides some evidence.]

On 2018-Dec-22, at 12:55, Mark Millard <marklmi at yahoo.com> wrote:

> [I found my E-mail records reporting successful builds using
> qemu-user-static from ports head -r484783 under FreeBSD
> head -r340287.]
> 
> On 2018-Dec-22, at 00:10, Mark Millard <marklmi at yahoo.com> wrote:
> 
>> [I messed up the freebsd-emulation email address the first time I sent
>> this. I also forgot to indicate the qemu-user-static vintage relationship.]
>> 
>> I had been reporting intermittent hang-ups for my amd64->{aarch64,armv7} port cross
>> builds in another message sequence. But it turns out that one thing I ran into
>> has hung-up every time, the same way, for amd64->armv7 cross builds:
>> multimedia/gstreamer1-qt at qt5 . So I extract the material here into a separate report
>> with some updated notes.
>> 
>> A little context: I had built from ports head -r484783 before under FreeBSD head
>> -r340287 (as I remember the version). Back then it did not have this problem that it
>> now has under FreeBSD head -r341836 . One ports-specific change was to force perl5.28
>> as the default instead of perl5.26 originally. In fact this is what drives what is
>> being rebuilt for my experiment that caught this. But I doubt the perl version is
>> important to the problem. The context has a Ryzen Threadripper 1950X and has been
>> tested both for FreeBSD under Hyper-V and for the same media native-booted. Both
>> hang-up at the same point as seen via ps or top. The native tools for cross-build
>> speedup were in use. Cross-builds targeting aarch64 did not get this problem but
>> targeting armv7 did. 121 of 129 armv7 ports built before the hang-up for the first
>> armv7 try.
>> 
>> ADDED: The qemu-user-static back with head -r340287 before installing the
>> updated ports would likely be different than the -r484783 vintage. So both
>> FreeBSD and qemu-user-static may have changed over the comparison.
> 
> CORRECTION to ADDED: Back on 2018-Nov-11 I reported successful cross-builds
> based on qemu-user-static from ports head -484783 --all built under FreeBSD
> head -r340287 . So the use of the perl5.28 as the forced-default and the
> newer FreeBSD head version -r341836 as the context are the differences here.
> 
>> The hang-up:
>> 
>> In the port rebuilds targeting armv7, multimedia/gstreamer1-qt at qt5 hung-up and timed
>> out. Looking during the wait in later tries shows something much like (from one of the
>> examples):
>> 
>> root       33719    0.0  0.0  12920  3528  0  I    11:40       0:00.03 | |           `-- sh: poudriere[FBSDFSSDjailArmV7-default][02]: build_pkg (gstreamer1-qt5-1.2.0_14) (sh)
>> root       41551    0.0  0.0  12920  3520  0  I    11:43       0:00.00 | |             `-- sh: poudriere[FBSDFSSDjailArmV7-default][02]: build_pkg (gstreamer1-qt5-1.2.0_14) (sh)
>> root       41552    0.0  0.0  10340  1744  0  IJ   11:43       0:00.01 | |               `-- /usr/bin/make -C /usr/ports/multimedia/gstreamer1-qt FLAVOR=qt5 build
>> root       41566    0.0  0.0  10236  1796  0  IJ   11:43       0:00.00 | |                 `-- /bin/sh -e -c (cd /wrkdirs/usr/ports/multimedia/gstreamer1-qt/work-qt5/.build; if ! /usr/bin/env QT_SELE
>> root       41567    0.0  0.0  89976 12896  0  IJ   11:43       0:00.07 | |                   `-- /usr/local/bin/qemu-arm-static ninja -j28 -v all
>> root       41585    0.0  0.0 102848 25056  0  IJ   11:43       0:00.10 | |                     |-- /usr/local/bin/qemu-arm-static /usr/local/bin/cmake -E cmake_autogen /wrkdirs/usr/ports/multimedia/g
>> root       41586    0.0  0.0 102852 25072  0  IJ   11:43       0:00.11 | |                     `-- /usr/local/bin/qemu-arm-static /usr/local/bin/cmake -E cmake_autogen /wrkdirs/usr/ports/multimedia/g
>> 
>> or as top showed it:
>> 
>> 41552 root          1  52    0    10M  1744K    0 wait    15   0:00   0.00% /usr/bin/make -C /usr/ports/multimedia/gstreamer1-qt FLAVOR=qt5 build
>> 41566 root          1  52    0    10M  1796K    0 wait     1   0:00   0.00% /bin/sh -e -c (cd /wrkdirs/usr/ports/multimedia/gstreamer1-qt/work-qt5/.build; if ! /usr/bin/env QT_SELECT=qt5 QMAKEMODULES
>> 41567 root          2  52    0    88M    13M    0 select   4   0:00   0.00% /usr/local/bin/qemu-arm-static ninja -j28 -v all
>> 41585 root          2  52    0   100M    24M    0 kqread   8   0:00   0.00% /usr/local/bin/qemu-arm-static /usr/local/bin/cmake -E cmake_autogen /wrkdirs/usr/ports/multimedia/gstreamer1-qt/work-qt5/.
>> 41586 root          2  52    0   100M    24M    0 kqread  22   0:00   0.00% /usr/local/bin/qemu-arm-static /usr/local/bin/cmake -E cmake_autogen /wrkdirs/usr/ports/multimedia/gstreamer1-qt/work-qt5/.
>> 
>> So: waiting in kqread trying to run cmake.
>> 
>> Unlike some intermittent hang-ups, attaching-then-detaching via gdb does not
>> resume the hung-up processes. Kills of the processes waiting on kqread stop
>> the build.
>> 
>> Given the prior ports have been built already, building just
>> multimedia/gstreamer1-qt at qt5 still gets the hang-up at the same point.
>> 
>> Building anything that requires multimedia/gstreamer1-qt at qt5 seems to be
>> solidly blocked in my environment.


I tried building multimedia/gstreamer1-qt at qt5 on a Orange Pi 2 2nd
Edition and the build did not hang-up. This was also based on FreeBSD
head -r341836 and ports head -r484783 .

This test was set up in part by copying over the
/usr/local/poudriere/data/packages/ material from what that did
cross build. So, for example, the cmake used should be a binary exact
match.

The FreeBSD head -r341836 was installed from the same buildworld
buildkernel tree that the cross-build's installworld was based on.

The problem is somehow specific to cross-builds (and so
qemu-user-static being involved).


Other evidence (official package build attempts):

I looked at beefy16.nyi.freebsd.org 's head-armv7-default and
beefy8.nyi.freebsd.org 's head-armv6-default histories and
the problem does not exist for the:

FreeBSD -r332419 ports -r467121

combination but exists for the later ones, starting with:

FreeBSD -r332632 ports -r467547

Interestingly qemu-sbruno (the master port for qemu-user-static)
was not updated in that ports range, being from -r463452 .

There was a cmake change at -r467437 but the more modern
native result suggests cmake is not currently contributing
(and, so, likely was not the issue back then).

That possibly leaves qemu-user-static for targeting armv7 (and v6)
misinterpreting something different from the different
FreeBSD versions. For example, there was a change to return
EAGAIN instead of EIO for certain conditions, between -r332419
and -r332632 : at -r332631 . (I do not know that it is
involved.)


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