From b8e64b2ab10a08e8ea223ac594066b8b35653471 Mon Sep 17 00:00:00 2001
From: Max Horstmann <maxhorstmann@microsoft.com>
Date: Thu, 26 Feb 2026 15:58:19 -0500
Subject: [PATCH 1/2] add dummy bind mounts for testing

---
 src/Runner.Worker/JobExtension.cs | 22 ++++++++++++++++++++++
 src/Runner.Worker/JobRunner.cs    | 24 ++++++++++++++++++++++++
 2 files changed, 46 insertions(+)

diff --git a/src/Runner.Worker/JobExtension.cs b/src/Runner.Worker/JobExtension.cs
index c210ebeb80a..214946d6bff 100644
--- a/src/Runner.Worker/JobExtension.cs
+++ b/src/Runner.Worker/JobExtension.cs
@@ -536,6 +536,28 @@ public async Task FinalizeJob(IExecutionContext jobContext, Pipelines.AgentJobRe
                     context.Start();
                     context.Debug("Starting: Complete job");
 
+                    // Tear down bind mount /mnt/foo1
+                    Trace.Info("Tearing down bind mount.");
+                    try
+                    {
+                        var umountProcess = HostContext.CreateService<IProcessInvoker>();
+                        umountProcess.OutputDataReceived += (_, data) => Trace.Info(data.Data);
+                        umountProcess.ErrorDataReceived += (_, data) => Trace.Error(data.Data);
+                        await umountProcess.ExecuteAsync(
+                            workingDirectory: "/",
+                            fileName: "umount",
+                            arguments: "/mnt/foo1",
+                            environment: null,
+                            requireExitCodeZero: false,
+                            cancellationToken: jobContext.CancellationToken);
+                        Trace.Info("Bind mount /mnt/foo1 unmounted successfully.");
+                    }
+                    catch (Exception ex)
+                    {
+                        Trace.Warning($"Failed to unmount bind mount: {ex.Message}");
+                        context.Warning($"Failed to unmount /mnt/foo1: {ex.Message}");
+                    }
+
                     Trace.Info("Initialize Env context");
 
 #if OS_WINDOWS
diff --git a/src/Runner.Worker/JobRunner.cs b/src/Runner.Worker/JobRunner.cs
index 72ee5a403ad..770bd5b614b 100644
--- a/src/Runner.Worker/JobRunner.cs
+++ b/src/Runner.Worker/JobRunner.cs
@@ -178,6 +178,30 @@ public async Task<TaskResult> RunAsync(AgentJobRequestMessage message, Cancellat
                 _tempDirectoryManager = HostContext.GetService<ITempDirectoryManager>();
                 _tempDirectoryManager.InitializeTempDirectory(jobContext);
 
+                // Create bind mount /mnt/foo1 -> /tmp/foo1
+                Trace.Info("Setting up bind mount.");
+                try
+                {
+                    Directory.CreateDirectory("/tmp/foo1");
+                    Directory.CreateDirectory("/mnt/foo1");
+                    var mountProcess = HostContext.CreateService<IProcessInvoker>();
+                    mountProcess.OutputDataReceived += (_, data) => Trace.Info(data.Data);
+                    mountProcess.ErrorDataReceived += (_, data) => Trace.Error(data.Data);
+                    await mountProcess.ExecuteAsync(
+                        workingDirectory: workDirectory,
+                        fileName: "mount",
+                        arguments: "--bind /tmp/foo1 /mnt/foo1",
+                        environment: null,
+                        requireExitCodeZero: true,
+                        cancellationToken: jobContext.CancellationToken);
+                    Trace.Info("Bind mount /mnt/foo1 -> /tmp/foo1 created successfully.");
+                }
+                catch (Exception ex)
+                {
+                    Trace.Warning($"Failed to create bind mount: {ex.Message}");
+                    jobContext.Warning($"Failed to create bind mount /mnt/foo1: {ex.Message}");
+                }
+
                 // Get the job extension.
                 Trace.Info("Getting job extension.");
                 IJobExtension jobExtension = HostContext.CreateService<IJobExtension>();

From 0c27e9388f5f33d83b6a87d5f8c6f58771ad0f6c Mon Sep 17 00:00:00 2001
From: Max Horstmann <maxhorstmann@microsoft.com>
Date: Thu, 26 Feb 2026 16:31:22 -0500
Subject: [PATCH 2/2] check OS

---
 src/Runner.Worker/JobRunner.cs | 45 ++++++++++++++++++----------------
 1 file changed, 24 insertions(+), 21 deletions(-)

diff --git a/src/Runner.Worker/JobRunner.cs b/src/Runner.Worker/JobRunner.cs
index 770bd5b614b..30107101541 100644
--- a/src/Runner.Worker/JobRunner.cs
+++ b/src/Runner.Worker/JobRunner.cs
@@ -178,28 +178,31 @@ public async Task<TaskResult> RunAsync(AgentJobRequestMessage message, Cancellat
                 _tempDirectoryManager = HostContext.GetService<ITempDirectoryManager>();
                 _tempDirectoryManager.InitializeTempDirectory(jobContext);
 
-                // Create bind mount /mnt/foo1 -> /tmp/foo1
-                Trace.Info("Setting up bind mount.");
-                try
-                {
-                    Directory.CreateDirectory("/tmp/foo1");
-                    Directory.CreateDirectory("/mnt/foo1");
-                    var mountProcess = HostContext.CreateService<IProcessInvoker>();
-                    mountProcess.OutputDataReceived += (_, data) => Trace.Info(data.Data);
-                    mountProcess.ErrorDataReceived += (_, data) => Trace.Error(data.Data);
-                    await mountProcess.ExecuteAsync(
-                        workingDirectory: workDirectory,
-                        fileName: "mount",
-                        arguments: "--bind /tmp/foo1 /mnt/foo1",
-                        environment: null,
-                        requireExitCodeZero: true,
-                        cancellationToken: jobContext.CancellationToken);
-                    Trace.Info("Bind mount /mnt/foo1 -> /tmp/foo1 created successfully.");
-                }
-                catch (Exception ex)
+                // Create bind mount /mnt/foo1 -> /tmp/foo1 (Linux only)
+                if (Constants.Runner.Platform == Constants.OSPlatform.Linux)
                 {
-                    Trace.Warning($"Failed to create bind mount: {ex.Message}");
-                    jobContext.Warning($"Failed to create bind mount /mnt/foo1: {ex.Message}");
+                    Trace.Info("Setting up bind mount.");
+                    try
+                    {
+                        Directory.CreateDirectory("/tmp/foo1");
+                        Directory.CreateDirectory("/mnt/foo1");
+                        var mountProcess = HostContext.CreateService<IProcessInvoker>();
+                        mountProcess.OutputDataReceived += (_, data) => Trace.Info(data.Data);
+                        mountProcess.ErrorDataReceived += (_, data) => Trace.Error(data.Data);
+                        await mountProcess.ExecuteAsync(
+                            workingDirectory: workDirectory,
+                            fileName: "mount",
+                            arguments: "--bind /tmp/foo1 /mnt/foo1",
+                            environment: null,
+                            requireExitCodeZero: true,
+                            cancellationToken: jobContext.CancellationToken);
+                        Trace.Info("Bind mount /mnt/foo1 -> /tmp/foo1 created successfully.");
+                    }
+                    catch (Exception ex)
+                    {
+                        Trace.Warning($"Failed to create bind mount: {ex.Message}");
+                        jobContext.Warning($"Failed to create bind mount /mnt/foo1: {ex.Message}");
+                    }
                 }
 
                 // Get the job extension.