Add git 2.21 install from update_source

doc/development/architecture.md

@@ -676,7 +676,7 @@ We've also detailed [our architecture of GitLab.com](https://about.gitlab.com/ha
 [runner-gdk]: https://gitlab.com/gitlab-org/gitlab-development-kit/blob/master/doc/howto/runner.md
 [database-migrations-omnibus]: https://docs.gitlab.com/omnibus/settings/database.html#disabling-automatic-database-migration
 [database-migrations-charts]: https://docs.gitlab.com/charts/charts/gitlab/migrations/
-[database-migrations-source]: ../update/upgrading_from_source.md#13-install-libs-migrations-etc
+[database-migrations-source]: ../update/upgrading_from_source.md#14-install-libs-migrations-etc
 [certificate-management-omnibus]: https://docs.gitlab.com/omnibus/settings/ssl.html
 [certificate-management-charts]: https://docs.gitlab.com/charts/installation/tls.html
 [certificate-management-source]: ../install/installation.md#using-https

doc/update/upgrading_from_source.md

@@ -114,7 +114,47 @@ sudo ln -sf /usr/local/go/bin/{go,godoc,gofmt} /usr/local/bin/
 rm go1.10.5.linux-amd64.tar.gz
 ```
 
-### 6. Get latest code
+### 6. Update git
+
+NOTE: **Note:**
+GitLab 11.11 and higher only supports Git 2.21.x and newer, and
+[dropped support for older versions](https://gitlab.com/gitlab-org/gitlab-ce/issues/54255).
+Be sure to upgrade your installation if necessary.
+
+```bash
+# Make sure Git is version 2.21.0 or higher
+git --version
+
+# Remove packaged Git
+sudo apt-get remove git-core
+
+# Install dependencies
+sudo apt-get install -y libcurl4-openssl-dev libexpat1-dev gettext libz-dev libssl-dev build-essential
+
+# Download and compile pcre2 from source
+curl --silent --show-error --location https://ftp.pcre.org/pub/pcre/pcre2-10.33.tar.gz --output pcre2.tar.gz
+tar -xzf pcre2.tar.gz
+cd pcre2-10.33
+chmod +x configure
+./configure --prefix=/usr --enable-jit
+make
+make install
+
+# Download and compile from source
+cd /tmp
+curl --remote-name --location --progress https://www.kernel.org/pub/software/scm/git/git-2.21.0.tar.gz
+echo '85eca51c7404da75e353eba587f87fea9481ba41e162206a6f70ad8118147bee  git-2.21.0.tar.gz' | shasum -a256 -c - && tar -xzf git-2.21.0.tar.gz
+cd git-2.21.0/
+./configure --with-libpcre
+make prefix=/usr/local all
+
+# Install into /usr/local/bin
+sudo make prefix=/usr/local install
+
+# You should edit config/gitlab.yml, change the git -> bin_path to /usr/local/bin/git
+```
+
+### 7. Get latest code
 
 ```bash
 cd /home/git/gitlab
@@ -142,7 +182,7 @@ cd /home/git/gitlab
 sudo -u git -H git checkout BRANCH-ee
 ```
 
-### 7. Update gitlab-shell
+### 8. Update gitlab-shell
 
 ```bash
 cd /home/git/gitlab-shell
@@ -152,7 +192,7 @@ sudo -u git -H git checkout v$(</home/git/gitlab/GITLAB_SHELL_VERSION)
 sudo -u git -H bin/compile
 ```
 
-### 8. Update gitlab-workhorse
+### 9. Update gitlab-workhorse
 
 Install and compile gitlab-workhorse. GitLab-Workhorse uses
 [GNU Make](https://www.gnu.org/software/make/).
@@ -167,7 +207,7 @@ sudo -u git -H git checkout v$(</home/git/gitlab/GITLAB_WORKHORSE_VERSION)
 sudo -u git -H make
 ```
 
-### 9. Update Gitaly
+### 10. Update Gitaly
 
 #### Compile Gitaly
 
@@ -178,7 +218,7 @@ sudo -u git -H git checkout v$(</home/git/gitlab/GITALY_SERVER_VERSION)
 sudo -u git -H make
 ```
 
-### 10. Update gitlab-pages
+### 11. Update gitlab-pages
 
 #### Only needed if you use GitLab Pages
 
@@ -195,7 +235,7 @@ sudo -u git -H git checkout v$(</home/git/gitlab/GITLAB_PAGES_VERSION)
 sudo -u git -H make
 ```
 
-### 11. Update MySQL permissions
+### 12. Update MySQL permissions
 
 If you are using MySQL you need to grant the GitLab user the necessary
 permissions on the database:
@@ -217,7 +257,7 @@ You can make this setting permanent by adding it to your `my.cnf`:
 log_bin_trust_function_creators=1
 ```
 
-### 12. Update configuration files
+### 13. Update configuration files
 
 #### New configuration options for `gitlab.yml`
 
@@ -291,7 +331,7 @@ For Ubuntu 16.04.1 LTS:
 sudo systemctl daemon-reload
 ```
 
-### 13. Install libs, migrations, etc.
+### 14. Install libs, migrations, etc.
 
 ```bash
 cd /home/git/gitlab
@@ -323,14 +363,14 @@ sudo -u git -H bundle exec rake cache:clear RAILS_ENV=production
 **MySQL installations**: Run through the `MySQL strings limits` and `Tables and
 data conversion to utf8mb4` [tasks](../install/database_mysql.md).
 
-### 14. Start application
+### 15. Start application
 
 ```bash
 sudo service gitlab start
 sudo service nginx restart
 ```
 
-### 15. Check application status
+### 16. Check application status
 
 Check if GitLab and its environment are configured correctly: