Migrate VM shares from 9p to virtiofs; update QEMU and doctor

internal/vm/qemu.go

@@ -12,13 +12,14 @@ import (
 func buildQEMUCommand(cfg *config.Config, sshPort int, mounts []virtiofsd.Mount) []string {
 	memSize := cfg.VM.Memory
 
-	// vhost-user-fs requires shared memory backend
+	// vhost-user-fs requires shared memory backend with share=on
+	// We must specify memory size only via the memory backend and attach it to NUMA
+	// The -m flag must match the memory backend size for QEMU to be happy
 	args := []string{
-		"-machine", "q35",
+		"-machine", "q35,memory-backend=mem",
 		"-accel", "kvm",
 		"-cpu", "host",
 		"-object", fmt.Sprintf("memory-backend-memfd,id=mem,size=%s,share=on", memSize),
-		"-numa", "node,memdev=mem",
 		"-smp", strconv.Itoa(cfg.VM.CPUs),
 		"-display", "none",
 		"-daemonize",