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Several weeks ago, I wanted to try ASP.NET vNext on Linux. I tested on VirtualBox and bhyve (on two entirely different host machines), with Ubuntu 12.04, 14.04 and 14.10, both inside and outside of docker. The "dnu/kpm restore" would always crash with really weird errors: Inexplicable exceptions everywhere around the TLS stack (featuring null reference exceptions in Monitor.TryEnter), again and again, up to the big crescendo in which the entire mono runtime blows up in a segfault.
Today, I ran another attempt but to no avail. Once again, "dnu restore" failed in this strange way. A friend however succeeded without problems, so I started investigating and the culprit seems to be mono's sgen GC. While everything works flawlessly on kernel version 3.16.0-30-generic, dnu crashes on 3.16.0-31-generic (the same installation, everything unchanged, just booting a different kernel). However, it can be fixed by compiling mono with the boehm GC instead of sgen.
kernel \ mono gc sgen boehm
3.16.0-30-generic ☑ ☐ (not tested)
3.16.0-31-generic ☒ ☑
A collection of my finest dnu crashes: https://gist.github.com/main--/dd7d8f81654789a977d9
Today's testing was run on a fully updated Ubuntu trusty. Mono 3.12.1, the sgen one from the APT repo and the boehm one self-compiled.
Using the upcoming mono 4.0 release might fix some of these problems.
If you could provide your dnu version and the config you're trying to restore, I can look whether your problem persists on the newest mono release.
I was unable to reproduce the issue with the mono 4 alpha 1 tarball.
Fixed in mono 4.