Remount sysfs when entering again into host netns

Mirantis · Jul 3, 2018 · ecaa313 · ecaa313
1 parent 641c597
commit ecaa313
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Showing 4 changed files with 35 additions and 8 deletions.
diff --git a/pkg/nettools/nettools.go b/pkg/nettools/nettools.go
@@ -54,6 +54,7 @@ import (
 
  "github.com/Mirantis/virtlet/pkg/cni"
  "github.com/Mirantis/virtlet/pkg/network"
+ "github.com/Mirantis/virtlet/pkg/utils"
 )
 
 const (
@@ -770,6 +771,16 @@ func SetupContainerSideNetwork(info *cnicurrent.Result, nsPath string, allLinks
  // Jump into host netns to get vlan id of VF using its
  // master device.
  if err := hostNS.Do(func(ns.NetNS) error {
+ // switch /sys to corresponding one in netns
+ // to have the correct items under /sys/class/net
+ if err := utils.MountSysfs(); err != nil {
+ return err
+ }
+ defer func() {
+ if err := utils.UnmountSysfs(); err != nil {
+ glog.V(3).Infof("Warning, error during umount of /sys: %v", err)
+ }
+ }()
  var err error
  vlanID, err = getVfVlanID(pciAddress)
  return err
@@ -793,6 +804,16 @@ func SetupContainerSideNetwork(info *cnicurrent.Result, nsPath string, allLinks
  // Jump into host netns to set mac address and vlan id
  // of VF using its master device.
  if err := hostNS.Do(func(ns.NetNS) error {
+ // switch /sys to corresponding one in netns
+ // to have the correct items under /sys/class/net
+ if err := utils.MountSysfs(); err != nil {
+ return err
+ }
+ defer func() {
+ if err := utils.UnmountSysfs(); err != nil {
+ glog.V(3).Infof("Warning, error during umount of /sys: %v", err)
+ }
+ }()
  return setMacAndVlanOnVf(pciAddress, hwAddr, vlanID)
  }); err != nil {
  return nil, err

diff --git a/pkg/tapmanager/tapfdsource.go b/pkg/tapmanager/tapfdsource.go
@@ -35,6 +35,7 @@ import (
  "github.com/Mirantis/virtlet/pkg/dhcp"
  "github.com/Mirantis/virtlet/pkg/nettools"
  "github.com/Mirantis/virtlet/pkg/network"
+ "github.com/Mirantis/virtlet/pkg/utils"
 )
 
 const (
@@ -353,11 +354,11 @@ func (s *TapFDSource) setupNetNS(key string, pnd *PodNetworkDesc, initNet func(n
  if err := vmNS.Do(func(hostNS ns.NetNS) error {
  // switch /sys to corresponding one in netns
  // to have the correct items under /sys/class/net
- if err := mountSysfs(); err != nil {
+ if err := utils.MountSysfs(); err != nil {
  return err
  }
  defer func() {
- if err := unmountSysfs(); err != nil {
+ if err := utils.UnmountSysfs(); err != nil {
  glog.V(3).Infof("Warning, error during umount of /sys: %v", err)
  }
  }()

diff --git a/pkg/tapmanager/mountsysfs_linux.go → pkg/utils/mountsysfs_linux.go b/pkg/tapmanager/mountsysfs_linux.go → pkg/utils/mountsysfs_linux.go
@@ -16,16 +16,19 @@ See the License for the specific language governing permissions and
 limitations under the License.
 */
 
-package tapmanager
+package utils
 
 import (
  "syscall"
 )
 
-func mountSysfs() error {
+// MountSysfs adds new mount of sysfs on /sys to have a correct view
+// in current netns on /sys/class/net
+func MountSysfs() error {
  return syscall.Mount("none", "/sys", "sysfs", 0, "")
 }
 
-func unmountSysfs() error {
+// UnmountSysfs unmounts current fs bound to /sys
+func UnmountSysfs() error {
  return syscall.Unmount("/sys", syscall.MNT_DETACH)
 }
diff --git a/pkg/tapmanager/mountsysfs_unsupported.go → pkg/utils/mountsysfs_unsupported.go b/pkg/tapmanager/mountsysfs_unsupported.go → pkg/utils/mountsysfs_unsupported.go
@@ -16,16 +16,18 @@ See the License for the specific language governing permissions and
 limitations under the License.
 */
 
-package tapmanager
+package utils
 
 import (
  "errors"
 )
 
-func mountSysfs() error {
+// MountSysfs is a placeholder for unsupported systems
+func MountSysfs() error {
  return errors.New("not implemented")
 }
 
-func unmountSysfs() error {
+// UnmountSysfs is a placeholder for unsupported systems
+func UnmountSysfs() error {
  return errors.New("not implemented")
 }