qemu-arm-static crashes "segmentation fault" when running "git clone"

[Zcien Dor]

This is a reopen of #1869073 for `qemu-user-static/focal-updates,focal-security,now 1:4.2-3ubuntu6.17 amd64`.

`git clone` reproducably segfaults in `qemu-arm-static` chroot.

#1869073 mentions this should have been fixed for newer versions of QEMU, but for `focal` there's no newer version available, even in `focal-backports`.

[Paride Legovini (paride)]

Hi Zcien and thanks for this bug report. I can't reproduce the crash. I tried to setup a Focal arm64 chroot on both Focal and Impish host systems, always amd64. I tried to:

  git clone https://github.com/canonical/cloud-init # just a random one

and it always worked. I setup the chroots with (qemu-)debootstrap. I'm marking this bug report as Incomplete for the moment, as to confirm this is actually a bug and begin working on it we need steps to reproduce. If you can provide them please comment back and change the bug status back to New, we'll look at it again. Thanks!

[Zcien Dor (zciendor)]

It happens reproducibly during the [Armbian build](https://github.com/armbian/build). This is quite lengthy and complex setup, so there's unfortunately no 5 liner script I can provide for you to reproduce. You would have to clone the project and start the build chain and even then it takes around 30 minutes until you reach the point where the segfault is caused.

However, after upgrading from `focal` to `hirsute` the segfault is gone, which supports my initial suspicion that it's the qemu version which has this issue. `hirsute` ships qemu-user-static `1:5.2+dfsg-9ubuntu3.1`.

[Zcien Dor (zciendor)]

I just noticed you tried to reproduce for `arm64`. I forgot to mention, that I experience it for `armhf` (32 bit). Maybe this issue only occurs in the 32 bit architecture. Would you mind to try your test again with `armhf`?

[Christian Ehrhardt  (paelzer)]

Hi,
while there was no new insight for this bug you might try the builds in the PPAs in bug 1749393 which fix a very similar issue on arm64. There it was reproducible and we could identify the fix.
Maybe it is the same fix for you even if no one else could re-create your case exactly.

It would be great if you could give these builds (or the version once completely SRUed) a try and let us know if this also fixed the case for you.