diff --git a/grubby-bls b/grubby-bls
index af0d82d..0571a0b 100755
--- a/grubby-bls
+++ b/grubby-bls
@@ -502,6 +502,16 @@ update_bls_fragment() {
                 opts="$(echo "$opts" | sed -e 's/\//\\\//g')"
                 sed -i -e "s/^GRUB_CMDLINE_LINUX.*/GRUB_CMDLINE_LINUX=\\\"${opts}\\\"/" "${grub_etc_default}"
             fi
+
+	    if [[ -f /etc/kernel/cmdline ]]; then
+		sed -i "s/\(root=[^ ]*\) .*/\1 ${opts}/" /etc/kernel/cmdline
+	    else
+		# grub2-mkconfig creates this.  Do that now.
+		grub2-mkconfig -o /etc/grub2.cfg
+	    fi
+	    if [[ ! -f /etc/kernel/cmdline ]]; then
+		echo "No /etc/kernel/cmdline; please report a bug";
+	    fi
         fi
 
         old_args="$(grub2-editenv "${env}" list | grep kernelopts | sed -e "s/kernelopts=//")"
@@ -528,6 +538,20 @@ update_bls_fragment() {
 	fi
     done
 
+    if [[ $param = "ALL" && $bootloader = zipl ]] && [[ -n $remove_args || -n $add_args ]]; then
+	if [[ ! -f /etc/kernel/cmdline ]]; then
+	    # anaconda could pre-populate this file, but until then, most of
+	    # the time we'll just want the most recent one.  This is pretty
+	    # close to the current almost-correct behavior of falling back to
+	    # /proc/cmdline anyhow.
+	    echo "$(get_bls_args -1)" > /etc/kernel/cmdline
+	fi
+
+	read old_args < /etc/kernel/cmdline
+	local new_args="$(update_args "${old_args}" "${remove_args}" "${add_args}")"
+	echo "$new_args" > /etc/kernel/cmdline
+    fi
+
     update_grubcfg
 }
 
diff --git a/grubby.spec b/grubby.spec
index a44afa7..a6ef7ca 100644
--- a/grubby.spec
+++ b/grubby.spec
@@ -3,7 +3,7 @@
 
 Name: grubby
 Version: 8.40
-Release: 63%{?dist}
+Release: 64%{?dist}
 Summary: Command line tool for updating bootloader configs
 License: GPLv2+
 Source1: grubby-bls
@@ -83,6 +83,9 @@ fi
 %{_mandir}/man8/grubby.8*
 
 %changelog
+* Tue Aug 02 2022 Robbie Harwood <rharwood@redhat.com> - 8.40-64
+- Handle updating /etc/kernel/cmdline
+
 * Thu Jul 21 2022 Fedora Release Engineering <releng@fedoraproject.org> - 8.40-63
 - Rebuilt for https://fedoraproject.org/wiki/Fedora_37_Mass_Rebuild