From e4123a9a5c186b5cd751866d7e5a324669428bf6 Mon Sep 17 00:00:00 2001
From: Sean Klein <sean@oxide.computer>
Date: Mon, 1 Jul 2024 16:29:07 -0700
Subject: [PATCH] Add TODO, re: concurrency safety

---
 sled-agent/src/sled_agent.rs | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/sled-agent/src/sled_agent.rs b/sled-agent/src/sled_agent.rs
index dc8cf942e0..b7cc5b5be3 100644
--- a/sled-agent/src/sled_agent.rs
+++ b/sled-agent/src/sled_agent.rs
@@ -820,6 +820,17 @@ impl SledAgent {
         config: OmicronPhysicalDisksConfig,
     ) -> Result<DisksManagementResult, Error> {
         // First, tell the storage subsystem which disks should be managed.
+        //
+        // TODO: Do we want to prevent future calls to
+        // "omicron_physical_disks_ensure" until we finish flushing?
+        //
+        // Otherwise, we the following could occur:
+        //
+        // - Ensure Disks {A, B, C}
+        // - ... try to remove all non-conforming disks
+        // - Ensure Disks {A, B, C, D} concurrently
+        // - ... we remove an instance on disk "D" because the old flush is
+        // still happening?
         let disk_result =
             self.storage().omicron_physical_disks_ensure(config).await?;