Passenger fails to automatically compile native support on aarch64-linux due to permissions issues

[pkarjala]

I am attempting to resolve an issue where a fresh install of Passenger on Ubuntu 26.04 will not launch due to issues with being unable to automatically compile native support.

Apache Version: 2.4.66
Passenger Version: 6.2.0
Ruby Version: 3.4.10
OS: Ubuntu 26.04
Architecture: aarch64 (VirtualBox machine on macOS host)

passenger-config validate-install returns no issues with the install.

The following appears in the Apache error logs when attempting to visit the URL of the Rails application after a fresh install of Passenger:

App 85312 output:  [passenger_native_support.so] trying to compile for the current user (vagrant) and Ruby interpreter...
App 85312 output:      (set PASSENGER_COMPILE_NATIVE_SUPPORT_BINARY=0 to disable)
App 85312 output: /usr/share/rvm/rubies/ruby-3.4.10/lib/ruby/3.4.0/fileutils.rb:403:in 'Dir.mkdir': Read-only file system @ dir_s_mkdir - /home/vagrant/.passenger (Errno::EROFS)
App 85312 output:       from /usr/share/rvm/rubies/ruby-3.4.10/lib/ruby/3.4.0/fileutils.rb:403:in 'FileUtils.fu_mkdir'
App 85312 output:       from /usr/share/rvm/rubies/ruby-3.4.10/lib/ruby/3.4.0/fileutils.rb:381:in 'block (2 levels) in FileUtils.mkdir_p'
App 85312 output:       from /usr/share/rvm/rubies/ruby-3.4.10/lib/ruby/3.4.0/fileutils.rb:379:in 'Array#reverse_each'
App 85312 output:       from /usr/share/rvm/rubies/ruby-3.4.10/lib/ruby/3.4.0/fileutils.rb:379:in 'block in FileUtils.mkdir_p'
App 85312 output:       from /usr/share/rvm/rubies/ruby-3.4.10/lib/ruby/3.4.0/fileutils.rb:371:in 'Array#each'
App 85312 output:       from /usr/share/rvm/rubies/ruby-3.4.10/lib/ruby/3.4.0/fileutils.rb:371:in 'FileUtils.mkdir_p'
App 85312 output:       from /usr/lib/ruby/vendor_ruby/phusion_passenger/native_support.rb:299:in 'PhusionPassenger::NativeSupportLoader#mkdir'
App 85312 output:       from /usr/lib/ruby/vendor_ruby/phusion_passenger/native_support.rb:377:in 'block in PhusionPassenger::NativeSupportLoader#try_directories'
App 85312 output:       from /usr/lib/ruby/vendor_ruby/phusion_passenger/native_support.rb:375:in 'Array#each'
App 85312 output:       from /usr/lib/ruby/vendor_ruby/phusion_passenger/native_support.rb:375:in 'Enumerable#each_with_index'
App 85312 output:       from /usr/lib/ruby/vendor_ruby/phusion_passenger/native_support.rb:375:in 'PhusionPassenger::NativeSupportLoader#try_directories'
App 85312 output:       from /usr/lib/ruby/vendor_ruby/phusion_passenger/native_support.rb:333:in 'PhusionPassenger::NativeSupportLoader#compile'
App 85312 output:       from /usr/lib/ruby/vendor_ruby/phusion_passenger/native_support.rb:219:in 'PhusionPassenger::NativeSupportLoader#compile_and_load'
App 85312 output:       from /usr/lib/ruby/vendor_ruby/phusion_passenger/native_support.rb:52:in 'PhusionPassenger::NativeSupportLoader#start'
App 85312 output:       from /usr/lib/ruby/vendor_ruby/phusion_passenger/native_support.rb:448:in '<top (required)>'
App 85312 output:       from <internal:/usr/share/rvm/rubies/ruby-3.4.10/lib/ruby/3.4.0/rubygems/core_ext/kernel_require.rb>:136:in 'Kernel#require'
App 85312 output:       from <internal:/usr/share/rvm/rubies/ruby-3.4.10/lib/ruby/3.4.0/rubygems/core_ext/kernel_require.rb>:136:in 'Kernel#require'
App 85312 output:       from /usr/lib/ruby/vendor_ruby/phusion_passenger.rb:245:in 'PhusionPassenger.require_passenger_lib'
App 85312 output:       from /usr/lib/ruby/vendor_ruby/phusion_passenger/preloader_shared_helpers.rb:30:in '<top (required)>'
App 85312 output:       from <internal:/usr/share/rvm/rubies/ruby-3.4.10/lib/ruby/3.4.0/rubygems/core_ext/kernel_require.rb>:136:in 'Kernel#require'
App 85312 output:       from <internal:/usr/share/rvm/rubies/ruby-3.4.10/lib/ruby/3.4.0/rubygems/core_ext/kernel_require.rb>:136:in 'Kernel#require'
App 85312 output:       from /usr/lib/ruby/vendor_ruby/phusion_passenger.rb:245:in 'PhusionPassenger.require_passenger_lib'
App 85312 output:       from /usr/share/passenger/helper-scripts/rack-preloader.rb:60:in 'PhusionPassenger::App.init_passenger'
App 85312 output:       from /usr/share/passenger/helper-scripts/rack-preloader.rb:186:in '<module:App>'
App 85312 output:       from /usr/share/passenger/helper-scripts/rack-preloader.rb:32:in '<module:PhusionPassenger>'
App 85312 output:       from /usr/share/passenger/helper-scripts/rack-preloader.rb:30:in '<main>'
[ E 2026-08-24 10:22:56.6730 84957/Ti age/Cor/App/Implementation.cpp:218 ]: Could not spawn process for application /var/www/data-store26: The application process exited prematurely.
  Error ID: 558d6643
  Error details saved to: /tmp/passenger-error-VHSuVa.html

[ E 2026-08-24 10:22:56.6735 84957/T9 age/Cor/Con/CheckoutSession.cpp:368 ]: [Client 1-2] Cannot checkout session because a spawning error occurred. The identifier of the error is 558d6643. Please see earlier logs for details about the error.

Of note, the Apache config is set to use the vagrant user with PassengerUserSwitching on:

# Passenger server configuration options
PassengerUserSwitching on
PassengerDefaultUser vagrant
PassengerMaxPoolSize 1

<VirtualHost *:80>
    ServerAdmin webmaster@localhost
    ServerName 192.168.10.100

    # Rails server configuration
    RailsEnv development

    # Passenger virtual host configuration options
    PassengerRuby /usr/share/rvm/rubies/ruby-3.4.10/bin/ruby

    # Disable sendfile support because of virtualbox bug.
    # See: https://www.vagrantup.com/docs/synced-folders/virtualbox.html
    ServerSignature Off
    TraceEnable Off
    EnableSendfile Off

    DocumentRoot /var/www/data-store26/public
    <Directory />
        Options FollowSymLinks
        AllowOverride All
    </Directory>
    <Directory /var/www/html/>
        Options -Indexes +FollowSymLinks +MultiViews
        AllowOverride All
        Order allow,deny
        allow from all
    </Directory>

    ScriptAlias /cgi-bin/ /usr/lib/cgi-bin/
    <Directory "/usr/lib/cgi-bin">
        AllowOverride None
        Options +ExecCGI -MultiViews +SymLinksIfOwnerMatch
        Order allow,deny
        Allow from all
    </Directory>

    ErrorLog ${APACHE_LOG_DIR}/error.log

    # Possible values include: debug, info, notice, warn, error, crit,
    # alert, emerg.
    LogLevel warn

    CustomLog ${APACHE_LOG_DIR}/access.log combined

</VirtualHost>

I tried manually creating the requested resource and it continued to give permission issues for each nested directory and file it needed to create. The /home/vagrant directory has 750 permissions, which the vagrant user should have access to.

I was able to bypass the issue by manually running passenger-config build-native-support:

vagrant@vagrant:~$ passenger-config build-native-support
 [passenger_native_support.so] trying to compile for the current user (vagrant) and Ruby interpreter...
     (set PASSENGER_COMPILE_NATIVE_SUPPORT_BINARY=0 to disable)
     Compilation successful. The logs are here:
     /tmp/passenger_native_support-1o8kax7.log
 [passenger_native_support.so] successfully loaded.

This error was then resolved.

So I think there is something going on with permissions during this process that isn't allowing it to generate the necessary files to automate the build, but I'm still coming up short on what exactly it might be.

[CamJN]

When did the issue start for you? For example did you switch from an earlier Ubuntu version or was it the Passenger update that changed?

[pkarjala]

This was first noticed on a freshly installed Ubuntu 26.04 VM that was set up yesterday, with a fresh install of Passenger 6.2.0 from the APT repository. We did not see it on our Ubuntu 24.04 VMs. We are currently doing testing in preparation for our migration to Ubuntu 26.04.

[CamJN]

Had you tried 6.2.0 in your 24.04 vms?

[pkarjala]

Not yet, I can go boot up a 24.04 VM to see if the same occurs. Will report back.

[pkarjala]

Confirmed that this issue does not occur on Ubuntu 24.04 with a fresh install of Passenger 6.2.0.

Here are the logs from Apache:

App 27282 output:  [passenger_native_support.so] trying to compile for the current user (vagrant) and Ruby interpreter...
App 27282 output:      (set PASSENGER_COMPILE_NATIVE_SUPPORT_BINARY=0 to disable)
App 27282 output:      Compilation successful. The logs are here:
App 27282 output:      /tmp/passenger_native_support-3su4mu.log
App 27282 output:  [passenger_native_support.so] successfully loaded.

[CamJN]

Thanks that helps narrow it down.

[CamJN]

I think this must be a vagrant specific issue, I just created a 26.04 container, and ran the following steps, and verified it created the native extensions just fine:

export DEBIAN_FRONTEND=noninteractive
export TZ=America/Edmonton
apt update
apt install -y build-essential ruby apache2  software-properties-common
apt-get install -y dirmngr gnupg apt-transport-https ca-certificates curl
curl https://oss-binaries.phusionpassenger.com/auto-software-signing-gpg-key-2025.txt | gpg --dearmor > /etc/apt/trusted.gpg.d/phusion.gpg
echo deb https://oss-binaries.phusionpassenger.com/apt/passenger resolute main > /etc/apt/sources.list.d/passenger.list
apt-add-repository -y ppa:rael-gc/rvm
apt-get update
apt-get install -y libapache2-mod-passenger rvm
source /usr/share/rvm/scripts/rvm
rvm install ruby-3.4.10
gem install rack
useradd -m -g users vagrant
mkdir -p /var/www/data-store26/public
echo "run Proc.new{|env| [200, {'Content-Type' => 'text/html'}, env]}" > /var/www/data-store26/config.ru
chown vagrant: /var/www/data-store26/config.ru
cat > /etc/apache2/sites-enabled/000-default.conf <<EOF
<VirtualHost *:80>
    PassengerRuby /usr/share/rvm/gems/ruby-3.4.10/wrappers/ruby
    PassengerAppEnv development
    ServerAdmin webmaster@localhost
    DocumentRoot /var/www/data-store26/public
    ErrorLog ${APACHE_LOG_DIR}/error.log
    CustomLog ${APACHE_LOG_DIR}/access.log combined
</VirtualHost>
EOF
cat > /etc/apache2/mods-enabled/passenger.conf <<EOF
<IfModule mod_passenger.c>
  PassengerRoot /usr/lib/ruby/vendor_ruby/phusion_passenger/locations.ini
  PassengerDefaultRuby /usr/bin/passenger_free_ruby

  PassengerInstanceRegistryDir /var/run/passenger-instreg

  PassengerUserSwitching on
  PassengerDefaultUser vagrant
  PassengerMaxPoolSize 1
</IfModule>
EOF
apachectl restart
curl http://localhost/
tail /var/log/apache2/error.log
ls -la ~vagrant/.passenger/native_support/6.2.0/ruby-3.4.10-aarch64-linux/

If your vagrant user's home directory is mounted from the host perhaps there's an issue there?

[pkarjala]

I can confirm that the user's home directory is not host-mounted in this case. Let me run the setup without our scripts and mirror the steps you posted, and see if it reproduces the same issue.