docs: clarify that --karg can be passed multiple times

It is not clear from the current man-page that `--karg` can be
passed multiple times. From reading the code it seems to be the
case but because it's not obvious (to me) I also added a small
testcase to the CI to ensure that I'm not misreading things.

I added a small comment to the docs that it can be given
multiple times.

Signed-off-by: Michael Vogt <[email protected]>
Signed-off-by: Colin Walters <[email protected]>

docs/src/man/bootc-install-to-disk.md

@@ -96,7 +96,9 @@ disabled but where the target does have SELinux enabled.
 
 **\--karg**=*KARG*
 
-:   Add a kernel argument
+:   Add a kernel argument. This option can be provided multiple times.
+
+Example: \--karg=nosmt \--karg=console=ttyS0,114800n8
 
 **\--root-ssh-authorized-keys**=*ROOT_SSH_AUTHORIZED_KEYS*
 

docs/src/man/bootc-install-to-existing-root.md

@@ -84,7 +84,9 @@ disabled but where the target does have SELinux enabled.
 
 **\--karg**=*KARG*
 
-:   Add a kernel argument
+:   Add a kernel argument. This option can be provided multiple times.
+
+Example: \--karg=nosmt \--karg=console=ttyS0,114800n8
 
 **\--root-ssh-authorized-keys**=*ROOT_SSH_AUTHORIZED_KEYS*
 

docs/src/man/bootc-install-to-filesystem.md

@@ -98,7 +98,9 @@ disabled but where the target does have SELinux enabled.
 
 **\--karg**=*KARG*
 
-:   Add a kernel argument
+:   Add a kernel argument. This option can be provided multiple times.
+
+Example: \--karg=nosmt \--karg=console=ttyS0,114800n8
 
 **\--root-ssh-authorized-keys**=*ROOT_SSH_AUTHORIZED_KEYS*
 

lib/src/install.rs

@@ -133,8 +133,10 @@ pub(crate) struct InstallConfigOpts {
     #[serde(default)]
     pub(crate) disable_selinux: bool,
 
+    /// Add a kernel argument.  This option can be provided multiple times.
+    ///
+    /// Example: --karg=nosmt --karg=console=ttyS0,114800n8
     #[clap(long)]
-    /// Add a kernel argument
     karg: Option<Vec<String>>,
 
     /// The path to an `authorized_keys` that will be injected into the `root` account.