VM: Apply mount options to hotplugged disks

lxd-agent/events.go

@@ -1,6 +1,7 @@
 package main
 
 import (
+	"context"
 	"encoding/json"
 	"fmt"
 	"net/http"
@@ -161,8 +162,16 @@ func eventsProcess(event api.Event) {
 
 	_ = os.MkdirAll(e.Config["path"], 0755)
 
+	// Parse mount options, if provided.
+	var args []string
+	if len(e.Mount.Options) > 0 {
+		args = append(args, "-o", strings.Join(e.Mount.Options, ","))
+	}
+
+	args = append(args, "-t", "virtiofs", mntSource, e.Config["path"])
+
 	for i := 0; i < 5; i++ {
-		_, err = shared.RunCommand("mount", "-t", "virtiofs", mntSource, e.Config["path"])
+		_, err = shared.RunCommandContext(context.Background(), "mount", args...)
 		if err == nil {
 			l.Info("Mounted hotplug")
 			return

lxd/instance/drivers/driver_common.go

@@ -1201,7 +1201,7 @@ func (d *common) setCoreSched(pids []int) error {
 		args = append(args, strconv.Itoa(pid))
 	}
 
-	_, err := shared.RunCommand(d.state.OS.ExecPath, args...)
+	_, err := shared.RunCommandContext(context.Background(), d.state.OS.ExecPath, args...)
 	return err
 }
 
@@ -1575,12 +1575,25 @@ func (d *common) devicesUpdate(inst instance.Instance, removeDevices deviceConfi
 
 			if runConf != nil && len(runConf.Mounts) > 0 {
 				for _, opt := range runConf.Mounts[0].Opts {
-					if strings.HasPrefix(opt, "mountTag=") {
-						parts := strings.SplitN(opt, "=", 2)
-						event["mount"] = instancetype.VMAgentMount{
-							Source: parts[1],
-						}
+					key, value, _ := strings.Cut(opt, "=")
+					if key != "mountTag" {
+						continue
 					}
+
+					if value == "" {
+						return nil, errors.New(`Empty "mountTag" on device's mount options`)
+					}
+
+					agentMount := instancetype.VMAgentMount{
+						Source: value,
+					}
+
+					if shared.IsTrue(dev.Config()["readonly"]) {
+						// Tell the agent to mount with "ro" option for consistency.
+						agentMount.Options = []string{"ro"}
+					}
+
+					event["mount"] = agentMount
 				}
 			}