config: use dense indices for VMs

CreateVMConfig uses fileutil.ProcessTempDir to assign indices to VMs.
fileutil.ProcessTempDir generates unique indices globally across several processes.
This was required for old vm/qemu code that used the index to choose unique ssh port for the VM.
Now vm/qemu does not use index as port and this global index assignment started
causing problems for adb and gce. Adb really needs indexes to be dense --
index is used to choose adb device id (if we have 2 devices, index 3 causes
out of bounds panic). For gce it leads to creation of unnecessary VM instances
(if I set count=4, I want at most 4 VMs created).

Don't use fileutil.ProcessTempDir-generated index in CreateVMConfig
and instead just use the dense indices passed by caller.

1 files changed, 1 insertions, 1 deletions

diff --git a/config/config.go b/config/config.go
index 9a8562912..103238f0a 100644
--- a/config/config.go
+++ b/config/config.go
@@ -250,7 +250,7 @@ func CreateVMConfig(cfg *Config, index int) (*vm.Config, error) {
 	if index < 0 || index >= cfg.Count {
 		return nil, fmt.Errorf("invalid VM index %v (count %v)", index, cfg.Count)
 	}
-	workdir, index, err := fileutil.ProcessTempDir(cfg.Workdir)
+	workdir, err := fileutil.ProcessTempDir(cfg.Workdir)
 	if err != nil {
 		return nil, fmt.Errorf("failed to create instance temp dir: %v", err)
 	}