From 08091ba9fb1bbf34e723523779bca5d05f6b3177 Mon Sep 17 00:00:00 2001
From: David Calavera <david.calavera@gmail.com>
Date: Fri, 30 Oct 2015 19:00:01 -0400
Subject: [PATCH] Turn IPC unmount errors into warnings.

And do not try to unmount empty paths.

Because nobody should be woken up in the middle of the night for them.

Signed-off-by: David Calavera <david.calavera@gmail.com>
(cherry picked from commit a54d5932e3a644317c77d59bc5aee562841d5c20)
---
 daemon/container.go         |  4 +---
 daemon/container_unix.go    | 26 +++++++++++---------------
 daemon/container_windows.go |  3 +--
 daemon/daemon.go            |  5 ++---
 4 files changed, 15 insertions(+), 23 deletions(-)

diff --git a/daemon/container.go b/daemon/container.go
index 99c1d8447..ace100c7e 100644
--- a/daemon/container.go
+++ b/daemon/container.go
@@ -333,9 +333,7 @@ func (streamConfig *streamConfig) StderrPipe() io.ReadCloser {
 func (container *Container) cleanup() {
 	container.releaseNetwork()
 
-	if err := container.unmountIpcMounts(detachMounted); err != nil {
-		logrus.Errorf("%s: Failed to umount ipc filesystems: %v", container.ID, err)
-	}
+	container.unmountIpcMounts(detachMounted)
 
 	if err := container.Unmount(); err != nil {
 		logrus.Errorf("%s: Failed to umount filesystem: %v", container.ID, err)
diff --git a/daemon/container_unix.go b/daemon/container_unix.go
index 0035eeb57..9b55302d7 100644
--- a/daemon/container_unix.go
+++ b/daemon/container_unix.go
@@ -1456,22 +1456,21 @@ func (container *Container) setupIpcDirs() error {
 	return nil
 }
 
-func (container *Container) unmountIpcMounts(unmount func(pth string) error) error {
+func (container *Container) unmountIpcMounts(unmount func(pth string) error) {
 	if container.hostConfig.IpcMode.IsContainer() || container.hostConfig.IpcMode.IsHost() {
-		return nil
+		return
 	}
 
-	var errors []string
+	var warnings []string
 
 	if !container.hasMountFor("/dev/shm") {
 		shmPath, err := container.shmPath()
 		if err != nil {
 			logrus.Error(err)
-			errors = append(errors, err.Error())
-		} else {
+			warnings = append(warnings, err.Error())
+		} else if shmPath != "" {
 			if err := unmount(shmPath); err != nil {
-				logrus.Errorf("failed to umount %s: %v", shmPath, err)
-				errors = append(errors, err.Error())
+				warnings = append(warnings, fmt.Sprintf("failed to umount %s: %v", shmPath, err))
 			}
 
 		}
@@ -1481,20 +1480,17 @@ func (container *Container) unmountIpcMounts(unmount func(pth string) error) err
 		mqueuePath, err := container.mqueuePath()
 		if err != nil {
 			logrus.Error(err)
-			errors = append(errors, err.Error())
-		} else {
+			warnings = append(warnings, err.Error())
+		} else if mqueuePath != "" {
 			if err := unmount(mqueuePath); err != nil {
-				logrus.Errorf("failed to umount %s: %v", mqueuePath, err)
-				errors = append(errors, err.Error())
+				warnings = append(warnings, fmt.Sprintf("failed to umount %s: %v", mqueuePath, err))
 			}
 		}
 	}
 
-	if len(errors) > 0 {
-		return fmt.Errorf("failed to cleanup ipc mounts:\n%v", strings.Join(errors, "\n"))
+	if len(warnings) > 0 {
+		logrus.Warnf("failed to cleanup ipc mounts:\n%v", strings.Join(warnings, "\n"))
 	}
-
-	return nil
 }
 
 func (container *Container) ipcMounts() []execdriver.Mount {
diff --git a/daemon/container_windows.go b/daemon/container_windows.go
index e97e753f5..ff33ba487 100644
--- a/daemon/container_windows.go
+++ b/daemon/container_windows.go
@@ -183,8 +183,7 @@ func (container *Container) removeMountPoints(_ bool) error {
 	return nil
 }
 
-func (container *Container) unmountIpcMounts(unmount func(pth string) error) error {
-	return nil
+func (container *Container) unmountIpcMounts(unmount func(pth string) error) {
 }
 
 func detachMounted(path string) error {
diff --git a/daemon/daemon.go b/daemon/daemon.go
index cf0430b29..f394e854a 100644
--- a/daemon/daemon.go
+++ b/daemon/daemon.go
@@ -223,9 +223,8 @@ func (daemon *Daemon) Register(container *Container) error {
 		}
 		daemon.execDriver.Terminate(cmd)
 
-		if err := container.unmountIpcMounts(mount.Unmount); err != nil {
-			logrus.Errorf("%s: Failed to umount ipc filesystems: %v", container.ID, err)
-		}
+		container.unmountIpcMounts(mount.Unmount)
+
 		if err := container.Unmount(); err != nil {
 			logrus.Debugf("unmount error %s", err)
 		}