Remove obsolete TODOs for b/38173783

The comments in the ticket indicate that this behavior
is fine and that the ticket should be closed, so we shouldn't
need pointers to the ticket.

PiperOrigin-RevId: 306266071

pkg/context/context.go

@@ -127,10 +127,6 @@ func (logContext) Value(key interface{}) interface{} {
 var bgContext = &logContext{Logger: log.Log()}
 
 // Background returns an empty context using the default logger.
-//
-// Users should be wary of using a Background context. Please tag any use with
-// FIXME(b/38173783) and a note to remove this use.
-//
 // Generally, one should use the Task as their context when available, or avoid
 // having to use a context in places where a Task is unavailable.
 //

pkg/sentry/arch/stack.go

@@ -97,7 +97,6 @@ func (s *Stack) Push(vals ...interface{}) (usermem.Addr, error) {
 		if c < 0 {
 			return 0, fmt.Errorf("bad binary.Size for %T", v)
 		}
-		// TODO(b/38173783): Use a real context.Context.
 		n, err := usermem.CopyObjectOut(context.Background(), s.IO, s.Bottom-usermem.Addr(c), norm, usermem.IOOpts{})
 		if err != nil || c != n {
 			return 0, err
@@ -121,11 +120,9 @@ func (s *Stack) Pop(vals ...interface{}) (usermem.Addr, error) {
 		var err error
 		if isVaddr {
 			value := s.Arch.Native(uintptr(0))
-			// TODO(b/38173783): Use a real context.Context.
 			n, err = usermem.CopyObjectIn(context.Background(), s.IO, s.Bottom, value, usermem.IOOpts{})
 			*vaddr = usermem.Addr(s.Arch.Value(value))
 		} else {
-			// TODO(b/38173783): Use a real context.Context.
 			n, err = usermem.CopyObjectIn(context.Background(), s.IO, s.Bottom, v, usermem.IOOpts{})
 		}
 		if err != nil {

pkg/sentry/fs/gofer/file_state.go

@@ -34,7 +34,6 @@ func (f *fileOperations) afterLoad() {
 		flags := f.flags
 		flags.Truncate = false
 
-		// TODO(b/38173783): Context is not plumbed to save/restore.
 		f.handles, err = f.inodeOperations.fileState.getHandles(context.Background(), flags, f.inodeOperations.cachingInodeOps)
 		if err != nil {
 			return fmt.Errorf("failed to re-open handle: %v", err)

pkg/sentry/fs/gofer/handles.go

@@ -57,7 +57,6 @@ func (h *handles) DecRef() {
 				}
 			}
 		}
-		// FIXME(b/38173783): Context is not plumbed here.
 		if err := h.File.close(context.Background()); err != nil {
 			log.Warningf("error closing p9 file: %v", err)
 		}

pkg/sentry/fs/gofer/inode_state.go

@@ -123,7 +123,6 @@ func (i *inodeFileState) afterLoad() {
 			// beforeSave.
 			return fmt.Errorf("failed to find path for inode number %d. Device %s contains %s", i.sattr.InodeID, i.s.connID, fs.InodeMappings(i.s.inodeMappings))
 		}
-		// TODO(b/38173783): Context is not plumbed to save/restore.
 		ctx := &dummyClockContext{context.Background()}
 
 		_, i.file, err = i.s.attach.walk(ctx, splitAbsolutePath(name))

pkg/sentry/fs/gofer/session_state.go

@@ -104,7 +104,6 @@ func (s *session) afterLoad() {
 	// If private unix sockets are enabled, create and fill the session's endpoint
 	// maps.
 	if opts.privateunixsocket {
-		// TODO(b/38173783): Context is not plumbed to save/restore.
 		ctx := &dummyClockContext{context.Background()}
 
 		if err = s.restoreEndpointMaps(ctx); err != nil {

pkg/sentry/fs/inode.go

@@ -102,7 +102,6 @@ func (i *Inode) DecRef() {
 
 // destroy releases the Inode and releases the msrc reference taken.
 func (i *Inode) destroy() {
-	// FIXME(b/38173783): Context is not plumbed here.
 	ctx := context.Background()
 	if err := i.WriteOut(ctx); err != nil {
 		// FIXME(b/65209558): Mark as warning again once noatime is

pkg/sentry/kernel/shm/shm.go

@@ -461,7 +461,7 @@ func (s *Shm) AddMapping(ctx context.Context, _ memmap.MappingSpace, _ usermem.A
 func (s *Shm) RemoveMapping(ctx context.Context, _ memmap.MappingSpace, _ usermem.AddrRange, _ uint64, _ bool) {
 	s.mu.Lock()
 	defer s.mu.Unlock()
-	// TODO(b/38173783): RemoveMapping may be called during task exit, when ctx
+	// RemoveMapping may be called during task exit, when ctx
 	// is context.Background. Gracefully handle missing clocks. Failing to
 	// update the detach time in these cases is ok, since no one can observe the
 	// omission.

pkg/sentry/kernel/task_context.go

@@ -58,7 +58,6 @@ func (tc *TaskContext) release() {
 	// Nil out pointers so that if the task is saved after release, it doesn't
 	// follow the pointers to possibly now-invalid objects.
 	if tc.MemoryManager != nil {
-		// TODO(b/38173783)
 		tc.MemoryManager.DecUsers(context.Background())
 		tc.MemoryManager = nil
 	}

pkg/sentry/kernel/task_signals.go

@@ -513,8 +513,6 @@ func (t *Task) canReceiveSignalLocked(sig linux.Signal) bool {
 	if t.stop != nil {
 		return false
 	}
-	// - TODO(b/38173783): No special case for when t is also the sending task,
-	// because the identity of the sender is unknown.
 	// - Do not choose tasks that have already been interrupted, as they may be
 	// busy handling another signal.
 	if len(t.interruptChan) != 0 {

pkg/usermem/usermem.go

@@ -29,9 +29,6 @@ import (
 )
 
 // IO provides access to the contents of a virtual memory space.
-//
-// FIXME(b/38173783): Implementations of IO cannot expect ctx to contain any
-// meaningful data.
 type IO interface {
 	// CopyOut copies len(src) bytes from src to the memory mapped at addr. It
 	// returns the number of bytes copied. If the number of bytes copied is <