From 4cb99dc830e7f99063d5c46ca5cc92c84a1db327 Mon Sep 17 00:00:00 2001 From: Kevin Wang Date: Tue, 10 Nov 2026 00:12:22 -0800 Subject: [PATCH] fix(vmm): write instance info atomically prepare_mr_config_v3() rewrites .instance_info on every launch with a truncating fs::write. A failed write or power loss leaves the file empty, losing instance_id_seed and with it the instance ID that keys the VM's persistent disk. Use safe_write, as the guest-reported instance info path already does. Signed-off-by: Kevin Wang --- dstack/vmm/src/app/mr_config.rs | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/dstack/vmm/src/app/mr_config.rs b/dstack/vmm/src/app/mr_config.rs index e9aa83539..926bcc675 100644 --- a/dstack/vmm/src/app/mr_config.rs +++ b/dstack/vmm/src/app/mr_config.rs @@ -173,7 +173,7 @@ impl VmWorkDir { }; instance_info.app_id = app_id.clone(); instance_info.instance_id = instance_id.clone(); - fs::write( + safe_write::safe_write( self.instance_info_path(), serde_json::to_string(&instance_info).context("failed to serialize instance info")?, )