1 files changed, 11 insertions, 35 deletions

diff --git a/pkg/sentry/kernel/kernel.go b/pkg/sentry/kernel/kernel.go
index df5160b67..5dc821a48 100644
--- a/pkg/sentry/kernel/kernel.go
+++ b/pkg/sentry/kernel/kernel.go
@@ -57,7 +57,6 @@ import (
 	"gvisor.dev/gvisor/pkg/sentry/hostcpu"
 	"gvisor.dev/gvisor/pkg/sentry/inet"
 	"gvisor.dev/gvisor/pkg/sentry/kernel/auth"
-	"gvisor.dev/gvisor/pkg/sentry/kernel/epoll"
 	"gvisor.dev/gvisor/pkg/sentry/kernel/futex"
 	"gvisor.dev/gvisor/pkg/sentry/kernel/sched"
 	ktime "gvisor.dev/gvisor/pkg/sentry/kernel/time"
@@ -78,11 +77,19 @@ import (
 	"gvisor.dev/gvisor/pkg/tcpip"
 )
 
-// VFS2Enabled is set to true when VFS2 is enabled. Added as a global for allow
-// easy access everywhere. To be removed once VFS2 becomes the default.
+// VFS2Enabled is set to true when VFS2 is enabled. Added as a global to allow
+// easy access everywhere.
+//
+// TODO(gvisor.dev/issue/1624): Remove when VFS1 is no longer used.
 var VFS2Enabled = false
 
-// FUSEEnabled is set to true when FUSE is enabled. Added as a global for allow
+// LISAFSEnabled is set to true when lisafs protocol is enabled. Added as a
+// global to allow easy access everywhere.
+//
+// TODO(gvisor.dev/issue/6319): Remove when lisafs is default.
+var LISAFSEnabled = false
+
+// FUSEEnabled is set to true when FUSE is enabled. Added as a global to allow
 // easy access everywhere. To be removed once FUSE is completed.
 var FUSEEnabled = false
 
@@ -478,11 +485,6 @@ func (k *Kernel) SaveTo(ctx context.Context, w wire.Writer) error {
 			return err
 		}
 
-		// Remove all epoll waiter objects from underlying wait queues.
-		// NOTE: for programs to resume execution in future snapshot scenarios,
-		// we will need to re-establish these waiter objects after saving.
-		k.tasks.unregisterEpollWaiters(ctx)
-
 		// Clear the dirent cache before saving because Dirents must be Loaded in a
 		// particular order (parents before children), and Loading dirents from a cache
 		// breaks that order.
@@ -615,32 +617,6 @@ func (k *Kernel) flushWritesToFiles(ctx context.Context) error {
 	})
 }
 
-// Preconditions: !VFS2Enabled.
-func (ts *TaskSet) unregisterEpollWaiters(ctx context.Context) {
-	ts.mu.RLock()
-	defer ts.mu.RUnlock()
-
-	// Tasks that belong to the same process could potentially point to the
-	// same FDTable. So we retain a map of processed ones to avoid
-	// processing the same FDTable multiple times.
-	processed := make(map[*FDTable]struct{})
-	for t := range ts.Root.tids {
-		// We can skip locking Task.mu here since the kernel is paused.
-		if t.fdTable == nil {
-			continue
-		}
-		if _, ok := processed[t.fdTable]; ok {
-			continue
-		}
-		t.fdTable.forEach(ctx, func(_ int32, file *fs.File, _ *vfs.FileDescription, _ FDFlags) {
-			if e, ok := file.FileOperations.(*epoll.EventPoll); ok {
-				e.UnregisterEpollWaiters()
-			}
-		})
-		processed[t.fdTable] = struct{}{}
-	}
-}
-
 // Preconditions: The kernel must be paused.
 func (k *Kernel) invalidateUnsavableMappings(ctx context.Context) error {
 	invalidated := make(map[*mm.MemoryManager]struct{})