Callisto13 / srcu-race-repro

https://queenofdowntime.com/blog/inotify-release-deadlock-envoy

These are some reproduction instructions and tools to recreate the SRCU data race problem identified by Denis Krien and detailed here.

Contents:

• Vagrantfile for Ubuntu Xenial with volume mount to load all contents into the VM
• inotify-test-c binary and inotify-test.c code
• inotify-test-rust binary and rust-test Cargo package
• run-envoy.sh script and envoy config directory

Installation:

git clone https://github.com/Callisto13/srcu-race-repro.git && cd srcu-race-repro

# on your host
vagrant up

vagrant ssh

# in vagrant VM
uname -r

# bump the kernel to 4.15
sudo su -
mkdir kern-415 && cd kern-415

wget https://kernel.ubuntu.com/~kernel-ppa/mainline/v4.15/linux-headers-4.15.0-041500_4.15.0-041500.201802011154_all.deb
wget https://kernel.ubuntu.com/~kernel-ppa/mainline/v4.15/linux-headers-4.15.0-041500-generic_4.15.0-041500.201802011154_amd64.deb
wget https://kernel.ubuntu.com/~kernel-ppa/mainline/v4.15/linux-image-4.15.0-041500-generic_4.15.0-041500.201802011154_amd64.deb

dpkg -i *.deb

reboot

# wait up to 2 minutes
vagrant ssh

# in vagrant VM
uname -r # should return '4.15.0-041500-generic'

# install Envoy
# https://www.getenvoy.io/platforms/envoy/ubuntu/
envoy --version

Running:

vagrant ssh

cd /vagrant_data
sudo su -

# envoy
./run-envoy.sh

# rust program - run as many loops as you like/your machine can manage
touch target
while : ; do ./inotify-test-rust ; done &

# c program - run as many loops as you like/your machine can manage
touch target
while : ; do ./inotify-test-c target ; done &

# in another terminal pane
vagrant ssh
sudo su -

watch -n 0.1 "ps -eLo pid,comm,state,wchan | grep -E 'inotify|envoy|kworker'"

# enjoy

source code for both rust and c programs are included for editing