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-rw-r--r--pkg/sentry/kernel/epoll/epoll.go2
-rw-r--r--pkg/sentry/kernel/fd_table.go24
-rw-r--r--pkg/sentry/kernel/kernel.go40
-rw-r--r--pkg/sentry/kernel/semaphore/semaphore.go1
-rw-r--r--pkg/sentry/kernel/sessions.go2
-rw-r--r--pkg/sentry/kernel/task.go29
-rw-r--r--pkg/sentry/kernel/task_clone.go9
-rw-r--r--pkg/sentry/kernel/task_start.go4
-rw-r--r--pkg/sentry/kernel/thread_group.go7
9 files changed, 68 insertions, 50 deletions
diff --git a/pkg/sentry/kernel/epoll/epoll.go b/pkg/sentry/kernel/epoll/epoll.go
index 8bffb78fc..592650923 100644
--- a/pkg/sentry/kernel/epoll/epoll.go
+++ b/pkg/sentry/kernel/epoll/epoll.go
@@ -296,8 +296,10 @@ func (*readyCallback) Callback(w *waiter.Entry) {
e.waitingList.Remove(entry)
e.readyList.PushBack(entry)
entry.curList = &e.readyList
+ e.listsMu.Unlock()
e.Notify(waiter.EventIn)
+ return
}
e.listsMu.Unlock()
diff --git a/pkg/sentry/kernel/fd_table.go b/pkg/sentry/kernel/fd_table.go
index 58001d56c..d09d97825 100644
--- a/pkg/sentry/kernel/fd_table.go
+++ b/pkg/sentry/kernel/fd_table.go
@@ -191,10 +191,12 @@ func (f *FDTable) Size() int {
return int(size)
}
-// forEach iterates over all non-nil files.
+// forEach iterates over all non-nil files in sorted order.
//
// It is the caller's responsibility to acquire an appropriate lock.
func (f *FDTable) forEach(fn func(fd int32, file *fs.File, fileVFS2 *vfs.FileDescription, flags FDFlags)) {
+ // retries tracks the number of failed TryIncRef attempts for the same FD.
+ retries := 0
fd := int32(0)
for {
file, fileVFS2, flags, ok := f.getAll(fd)
@@ -204,17 +206,26 @@ func (f *FDTable) forEach(fn func(fd int32, file *fs.File, fileVFS2 *vfs.FileDes
switch {
case file != nil:
if !file.TryIncRef() {
+ retries++
+ if retries > 1000 {
+ panic(fmt.Sprintf("File in FD table has been destroyed. FD: %d, File: %+v, FileOps: %+v", fd, file, file.FileOperations))
+ }
continue // Race caught.
}
fn(fd, file, nil, flags)
file.DecRef()
case fileVFS2 != nil:
if !fileVFS2.TryIncRef() {
+ retries++
+ if retries > 1000 {
+ panic(fmt.Sprintf("File in FD table has been destroyed. FD: %d, File: %+v, Impl: %+v", fd, fileVFS2, fileVFS2.Impl()))
+ }
continue // Race caught.
}
fn(fd, nil, fileVFS2, flags)
fileVFS2.DecRef()
}
+ retries = 0
fd++
}
}
@@ -327,7 +338,7 @@ func (f *FDTable) NewFDVFS2(ctx context.Context, minfd int32, file *vfs.FileDesc
fd = f.next
}
for fd < end {
- if d, _, _ := f.get(fd); d == nil {
+ if d, _, _ := f.getVFS2(fd); d == nil {
f.setVFS2(fd, file, flags)
if fd == f.next {
// Update next search start position.
@@ -447,7 +458,10 @@ func (f *FDTable) GetVFS2(fd int32) (*vfs.FileDescription, FDFlags) {
}
}
-// GetFDs returns a list of valid fds.
+// GetFDs returns a sorted list of valid fds.
+//
+// Precondition: The caller must be running on the task goroutine, or Task.mu
+// must be locked.
func (f *FDTable) GetFDs() []int32 {
fds := make([]int32, 0, int(atomic.LoadInt32(&f.used)))
f.forEach(func(fd int32, _ *fs.File, _ *vfs.FileDescription, _ FDFlags) {
@@ -522,7 +536,9 @@ func (f *FDTable) Remove(fd int32) (*fs.File, *vfs.FileDescription) {
case orig2 != nil:
orig2.IncRef()
}
- f.setAll(fd, nil, nil, FDFlags{}) // Zap entry.
+ if orig != nil || orig2 != nil {
+ f.setAll(fd, nil, nil, FDFlags{}) // Zap entry.
+ }
return orig, orig2
}
diff --git a/pkg/sentry/kernel/kernel.go b/pkg/sentry/kernel/kernel.go
index 1d627564f..6feda8fa1 100644
--- a/pkg/sentry/kernel/kernel.go
+++ b/pkg/sentry/kernel/kernel.go
@@ -467,6 +467,11 @@ func (k *Kernel) flushMountSourceRefs() error {
//
// Precondition: Must be called with the kernel paused.
func (ts *TaskSet) forEachFDPaused(f func(*fs.File, *vfs.FileDescription) error) (err error) {
+ // TODO(gvisor.dev/issue/1663): Add save support for VFS2.
+ if VFS2Enabled {
+ return nil
+ }
+
ts.mu.RLock()
defer ts.mu.RUnlock()
for t := range ts.Root.tids {
@@ -484,7 +489,7 @@ func (ts *TaskSet) forEachFDPaused(f func(*fs.File, *vfs.FileDescription) error)
}
func (ts *TaskSet) flushWritesToFiles(ctx context.Context) error {
- // TODO(gvisor.dev/issues/1663): Add save support for VFS2.
+ // TODO(gvisor.dev/issue/1663): Add save support for VFS2.
return ts.forEachFDPaused(func(file *fs.File, _ *vfs.FileDescription) error {
if flags := file.Flags(); !flags.Write {
return nil
@@ -533,6 +538,11 @@ func (k *Kernel) invalidateUnsavableMappings(ctx context.Context) error {
}
func (ts *TaskSet) unregisterEpollWaiters() {
+ // TODO(gvisor.dev/issue/1663): Add save support for VFS2.
+ if VFS2Enabled {
+ return
+ }
+
ts.mu.RLock()
defer ts.mu.RUnlock()
for t := range ts.Root.tids {
@@ -1005,11 +1015,14 @@ func (k *Kernel) pauseTimeLocked() {
// This means we'll iterate FDTables shared by multiple tasks repeatedly,
// but ktime.Timer.Pause is idempotent so this is harmless.
if t.fdTable != nil {
- t.fdTable.forEach(func(_ int32, file *fs.File, _ *vfs.FileDescription, _ FDFlags) {
- if tfd, ok := file.FileOperations.(*timerfd.TimerOperations); ok {
- tfd.PauseTimer()
- }
- })
+ // TODO(gvisor.dev/issue/1663): Add save support for VFS2.
+ if !VFS2Enabled {
+ t.fdTable.forEach(func(_ int32, file *fs.File, _ *vfs.FileDescription, _ FDFlags) {
+ if tfd, ok := file.FileOperations.(*timerfd.TimerOperations); ok {
+ tfd.PauseTimer()
+ }
+ })
+ }
}
}
k.timekeeper.PauseUpdates()
@@ -1034,12 +1047,15 @@ func (k *Kernel) resumeTimeLocked() {
it.ResumeTimer()
}
}
- if t.fdTable != nil {
- t.fdTable.forEach(func(_ int32, file *fs.File, _ *vfs.FileDescription, _ FDFlags) {
- if tfd, ok := file.FileOperations.(*timerfd.TimerOperations); ok {
- tfd.ResumeTimer()
- }
- })
+ // TODO(gvisor.dev/issue/1663): Add save support for VFS2.
+ if !VFS2Enabled {
+ if t.fdTable != nil {
+ t.fdTable.forEach(func(_ int32, file *fs.File, _ *vfs.FileDescription, _ FDFlags) {
+ if tfd, ok := file.FileOperations.(*timerfd.TimerOperations); ok {
+ tfd.ResumeTimer()
+ }
+ })
+ }
}
}
}
diff --git a/pkg/sentry/kernel/semaphore/semaphore.go b/pkg/sentry/kernel/semaphore/semaphore.go
index 1000f3287..c00fa1138 100644
--- a/pkg/sentry/kernel/semaphore/semaphore.go
+++ b/pkg/sentry/kernel/semaphore/semaphore.go
@@ -554,6 +554,7 @@ func (s *sem) wakeWaiters() {
for w := s.waiters.Front(); w != nil; {
if s.value < w.value {
// Still blocked, skip it.
+ w = w.Next()
continue
}
w.ch <- struct{}{}
diff --git a/pkg/sentry/kernel/sessions.go b/pkg/sentry/kernel/sessions.go
index 047b5214d..0e19286de 100644
--- a/pkg/sentry/kernel/sessions.go
+++ b/pkg/sentry/kernel/sessions.go
@@ -246,7 +246,7 @@ func (pg *ProcessGroup) SendSignal(info *arch.SignalInfo) error {
var lastErr error
for tg := range tasks.Root.tgids {
- if tg.ProcessGroup() == pg {
+ if tg.processGroup == pg {
tg.signalHandlers.mu.Lock()
infoCopy := *info
if err := tg.leader.sendSignalLocked(&infoCopy, true /*group*/); err != nil {
diff --git a/pkg/sentry/kernel/task.go b/pkg/sentry/kernel/task.go
index c0dbbe890..8452ddf5b 100644
--- a/pkg/sentry/kernel/task.go
+++ b/pkg/sentry/kernel/task.go
@@ -555,13 +555,6 @@ type Task struct {
//
// startTime is protected by mu.
startTime ktime.Time
-
- // oomScoreAdj is the task's OOM score adjustment. This is currently not
- // used but is maintained for consistency.
- // TODO(gvisor.dev/issue/1967)
- //
- // oomScoreAdj is protected by mu, and is owned by the task goroutine.
- oomScoreAdj int32
}
func (t *Task) savePtraceTracer() *Task {
@@ -856,27 +849,17 @@ func (t *Task) ContainerID() string {
return t.containerID
}
-// OOMScoreAdj gets the task's OOM score adjustment.
-func (t *Task) OOMScoreAdj() (int32, error) {
- t.mu.Lock()
- defer t.mu.Unlock()
- if t.ExitState() == TaskExitDead {
- return 0, syserror.ESRCH
- }
- return t.oomScoreAdj, nil
+// OOMScoreAdj gets the task's thread group's OOM score adjustment.
+func (t *Task) OOMScoreAdj() int32 {
+ return atomic.LoadInt32(&t.tg.oomScoreAdj)
}
-// SetOOMScoreAdj sets the task's OOM score adjustment. The value should be
-// between -1000 and 1000 inclusive.
+// SetOOMScoreAdj sets the task's thread group's OOM score adjustment. The
+// value should be between -1000 and 1000 inclusive.
func (t *Task) SetOOMScoreAdj(adj int32) error {
- t.mu.Lock()
- defer t.mu.Unlock()
- if t.ExitState() == TaskExitDead {
- return syserror.ESRCH
- }
if adj > 1000 || adj < -1000 {
return syserror.EINVAL
}
- t.oomScoreAdj = adj
+ atomic.StoreInt32(&t.tg.oomScoreAdj, adj)
return nil
}
diff --git a/pkg/sentry/kernel/task_clone.go b/pkg/sentry/kernel/task_clone.go
index dda502bb8..e1ecca99e 100644
--- a/pkg/sentry/kernel/task_clone.go
+++ b/pkg/sentry/kernel/task_clone.go
@@ -15,6 +15,8 @@
package kernel
import (
+ "sync/atomic"
+
"gvisor.dev/gvisor/pkg/abi/linux"
"gvisor.dev/gvisor/pkg/bpf"
"gvisor.dev/gvisor/pkg/sentry/inet"
@@ -260,15 +262,11 @@ func (t *Task) Clone(opts *CloneOptions) (ThreadID, *SyscallControl, error) {
sh = sh.Fork()
}
tg = t.k.NewThreadGroup(tg.mounts, pidns, sh, opts.TerminationSignal, tg.limits.GetCopy())
+ tg.oomScoreAdj = atomic.LoadInt32(&t.tg.oomScoreAdj)
rseqAddr = t.rseqAddr
rseqSignature = t.rseqSignature
}
- adj, err := t.OOMScoreAdj()
- if err != nil {
- return 0, nil, err
- }
-
cfg := &TaskConfig{
Kernel: t.k,
ThreadGroup: tg,
@@ -287,7 +285,6 @@ func (t *Task) Clone(opts *CloneOptions) (ThreadID, *SyscallControl, error) {
RSeqAddr: rseqAddr,
RSeqSignature: rseqSignature,
ContainerID: t.ContainerID(),
- OOMScoreAdj: adj,
}
if opts.NewThreadGroup {
cfg.Parent = t
diff --git a/pkg/sentry/kernel/task_start.go b/pkg/sentry/kernel/task_start.go
index 2bbf48bb8..a5035bb7f 100644
--- a/pkg/sentry/kernel/task_start.go
+++ b/pkg/sentry/kernel/task_start.go
@@ -93,9 +93,6 @@ type TaskConfig struct {
// ContainerID is the container the new task belongs to.
ContainerID string
-
- // oomScoreAdj is the task's OOM score adjustment.
- OOMScoreAdj int32
}
// NewTask creates a new task defined by cfg.
@@ -146,7 +143,6 @@ func (ts *TaskSet) newTask(cfg *TaskConfig) (*Task, error) {
rseqSignature: cfg.RSeqSignature,
futexWaiter: futex.NewWaiter(),
containerID: cfg.ContainerID,
- oomScoreAdj: cfg.OOMScoreAdj,
}
t.creds.Store(cfg.Credentials)
t.endStopCond.L = &t.tg.signalHandlers.mu
diff --git a/pkg/sentry/kernel/thread_group.go b/pkg/sentry/kernel/thread_group.go
index 268f62e9d..52849f5b3 100644
--- a/pkg/sentry/kernel/thread_group.go
+++ b/pkg/sentry/kernel/thread_group.go
@@ -254,6 +254,13 @@ type ThreadGroup struct {
//
// tty is protected by the signal mutex.
tty *TTY
+
+ // oomScoreAdj is the thread group's OOM score adjustment. This is
+ // currently not used but is maintained for consistency.
+ // TODO(gvisor.dev/issue/1967)
+ //
+ // oomScoreAdj is accessed using atomic memory operations.
+ oomScoreAdj int32
}
// NewThreadGroup returns a new, empty thread group in PID namespace pidns. The
generated by cgit v1.2.3 (git 2.39.1) at 2025-01-10 18:22:14 +0000