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-rw-r--r--pkg/sentry/mm/BUILD2
-rw-r--r--pkg/sentry/mm/address_space.go46
-rw-r--r--pkg/sentry/mm/lifecycle.go37
-rw-r--r--pkg/sentry/mm/metadata.go10
-rw-r--r--pkg/sentry/mm/mm.go9
-rw-r--r--pkg/sentry/mm/mm_test.go2
6 files changed, 69 insertions, 37 deletions
diff --git a/pkg/sentry/mm/BUILD b/pkg/sentry/mm/BUILD
index e5729ced5..73591dab7 100644
--- a/pkg/sentry/mm/BUILD
+++ b/pkg/sentry/mm/BUILD
@@ -105,8 +105,8 @@ go_library(
"//pkg/safecopy",
"//pkg/safemem",
"//pkg/sentry/arch",
- "//pkg/sentry/fs",
"//pkg/sentry/fs/proc/seqfile",
+ "//pkg/sentry/fsbridge",
"//pkg/sentry/kernel/auth",
"//pkg/sentry/kernel/futex",
"//pkg/sentry/kernel/shm",
diff --git a/pkg/sentry/mm/address_space.go b/pkg/sentry/mm/address_space.go
index e58a63deb..0332fc71c 100644
--- a/pkg/sentry/mm/address_space.go
+++ b/pkg/sentry/mm/address_space.go
@@ -18,7 +18,7 @@ import (
"fmt"
"sync/atomic"
- "gvisor.dev/gvisor/pkg/atomicbitops"
+ "gvisor.dev/gvisor/pkg/context"
"gvisor.dev/gvisor/pkg/sentry/platform"
"gvisor.dev/gvisor/pkg/usermem"
)
@@ -39,11 +39,18 @@ func (mm *MemoryManager) AddressSpace() platform.AddressSpace {
//
// When this MemoryManager is no longer needed by a task, it should call
// Deactivate to release the reference.
-func (mm *MemoryManager) Activate() error {
+func (mm *MemoryManager) Activate(ctx context.Context) error {
// Fast path: the MemoryManager already has an active
// platform.AddressSpace, and we just need to indicate that we need it too.
- if atomicbitops.IncUnlessZeroInt32(&mm.active) {
- return nil
+ for {
+ active := atomic.LoadInt32(&mm.active)
+ if active == 0 {
+ // Fall back to the slow path.
+ break
+ }
+ if atomic.CompareAndSwapInt32(&mm.active, active, active+1) {
+ return nil
+ }
}
for {
@@ -85,16 +92,20 @@ func (mm *MemoryManager) Activate() error {
if as == nil {
// AddressSpace is unavailable, we must wait.
//
- // activeMu must not be held while waiting, as the user
- // of the address space we are waiting on may attempt
- // to take activeMu.
- //
- // Don't call UninterruptibleSleepStart to register the
- // wait to allow the watchdog stuck task to trigger in
- // case a process is starved waiting for the address
- // space.
+ // activeMu must not be held while waiting, as the user of the address
+ // space we are waiting on may attempt to take activeMu.
mm.activeMu.Unlock()
+
+ sleep := mm.p.CooperativelySchedulesAddressSpace() && mm.sleepForActivation
+ if sleep {
+ // Mark this task sleeping while waiting for the address space to
+ // prevent the watchdog from reporting it as a stuck task.
+ ctx.UninterruptibleSleepStart(false)
+ }
<-c
+ if sleep {
+ ctx.UninterruptibleSleepFinish(false)
+ }
continue
}
@@ -118,8 +129,15 @@ func (mm *MemoryManager) Activate() error {
func (mm *MemoryManager) Deactivate() {
// Fast path: this is not the last goroutine to deactivate the
// MemoryManager.
- if atomicbitops.DecUnlessOneInt32(&mm.active) {
- return
+ for {
+ active := atomic.LoadInt32(&mm.active)
+ if active == 1 {
+ // Fall back to the slow path.
+ break
+ }
+ if atomic.CompareAndSwapInt32(&mm.active, active, active-1) {
+ return
+ }
}
mm.activeMu.Lock()
diff --git a/pkg/sentry/mm/lifecycle.go b/pkg/sentry/mm/lifecycle.go
index 47b8fbf43..d8a5b9d29 100644
--- a/pkg/sentry/mm/lifecycle.go
+++ b/pkg/sentry/mm/lifecycle.go
@@ -18,7 +18,6 @@ import (
"fmt"
"sync/atomic"
- "gvisor.dev/gvisor/pkg/atomicbitops"
"gvisor.dev/gvisor/pkg/context"
"gvisor.dev/gvisor/pkg/sentry/arch"
"gvisor.dev/gvisor/pkg/sentry/limits"
@@ -29,16 +28,17 @@ import (
)
// NewMemoryManager returns a new MemoryManager with no mappings and 1 user.
-func NewMemoryManager(p platform.Platform, mfp pgalloc.MemoryFileProvider) *MemoryManager {
+func NewMemoryManager(p platform.Platform, mfp pgalloc.MemoryFileProvider, sleepForActivation bool) *MemoryManager {
return &MemoryManager{
- p: p,
- mfp: mfp,
- haveASIO: p.SupportsAddressSpaceIO(),
- privateRefs: &privateRefs{},
- users: 1,
- auxv: arch.Auxv{},
- dumpability: UserDumpable,
- aioManager: aioManager{contexts: make(map[uint64]*AIOContext)},
+ p: p,
+ mfp: mfp,
+ haveASIO: p.SupportsAddressSpaceIO(),
+ privateRefs: &privateRefs{},
+ users: 1,
+ auxv: arch.Auxv{},
+ dumpability: UserDumpable,
+ aioManager: aioManager{contexts: make(map[uint64]*AIOContext)},
+ sleepForActivation: sleepForActivation,
}
}
@@ -80,9 +80,10 @@ func (mm *MemoryManager) Fork(ctx context.Context) (*MemoryManager, error) {
envv: mm.envv,
auxv: append(arch.Auxv(nil), mm.auxv...),
// IncRef'd below, once we know that there isn't an error.
- executable: mm.executable,
- dumpability: mm.dumpability,
- aioManager: aioManager{contexts: make(map[uint64]*AIOContext)},
+ executable: mm.executable,
+ dumpability: mm.dumpability,
+ aioManager: aioManager{contexts: make(map[uint64]*AIOContext)},
+ sleepForActivation: mm.sleepForActivation,
}
// Copy vmas.
@@ -229,7 +230,15 @@ func (mm *MemoryManager) Fork(ctx context.Context) (*MemoryManager, error) {
// IncUsers increments mm's user count and returns true. If the user count is
// already 0, IncUsers does nothing and returns false.
func (mm *MemoryManager) IncUsers() bool {
- return atomicbitops.IncUnlessZeroInt32(&mm.users)
+ for {
+ users := atomic.LoadInt32(&mm.users)
+ if users == 0 {
+ return false
+ }
+ if atomic.CompareAndSwapInt32(&mm.users, users, users+1) {
+ return true
+ }
+ }
}
// DecUsers decrements mm's user count. If the user count reaches 0, all
diff --git a/pkg/sentry/mm/metadata.go b/pkg/sentry/mm/metadata.go
index f550acae0..6a49334f4 100644
--- a/pkg/sentry/mm/metadata.go
+++ b/pkg/sentry/mm/metadata.go
@@ -16,7 +16,7 @@ package mm
import (
"gvisor.dev/gvisor/pkg/sentry/arch"
- "gvisor.dev/gvisor/pkg/sentry/fs"
+ "gvisor.dev/gvisor/pkg/sentry/fsbridge"
"gvisor.dev/gvisor/pkg/usermem"
)
@@ -132,7 +132,7 @@ func (mm *MemoryManager) SetAuxv(auxv arch.Auxv) {
//
// An additional reference will be taken in the case of a non-nil executable,
// which must be released by the caller.
-func (mm *MemoryManager) Executable() *fs.Dirent {
+func (mm *MemoryManager) Executable() fsbridge.File {
mm.metadataMu.Lock()
defer mm.metadataMu.Unlock()
@@ -147,15 +147,15 @@ func (mm *MemoryManager) Executable() *fs.Dirent {
// SetExecutable sets the executable.
//
// This takes a reference on d.
-func (mm *MemoryManager) SetExecutable(d *fs.Dirent) {
+func (mm *MemoryManager) SetExecutable(file fsbridge.File) {
mm.metadataMu.Lock()
// Grab a new reference.
- d.IncRef()
+ file.IncRef()
// Set the executable.
orig := mm.executable
- mm.executable = d
+ mm.executable = file
mm.metadataMu.Unlock()
diff --git a/pkg/sentry/mm/mm.go b/pkg/sentry/mm/mm.go
index 09e582dd3..c2195ae11 100644
--- a/pkg/sentry/mm/mm.go
+++ b/pkg/sentry/mm/mm.go
@@ -37,7 +37,7 @@ package mm
import (
"gvisor.dev/gvisor/pkg/safemem"
"gvisor.dev/gvisor/pkg/sentry/arch"
- "gvisor.dev/gvisor/pkg/sentry/fs"
+ "gvisor.dev/gvisor/pkg/sentry/fsbridge"
"gvisor.dev/gvisor/pkg/sentry/memmap"
"gvisor.dev/gvisor/pkg/sentry/pgalloc"
"gvisor.dev/gvisor/pkg/sentry/platform"
@@ -215,7 +215,7 @@ type MemoryManager struct {
// is not nil, it holds a reference on the Dirent.
//
// executable is protected by metadataMu.
- executable *fs.Dirent
+ executable fsbridge.File
// dumpability describes if and how this MemoryManager may be dumped to
// userspace.
@@ -226,6 +226,11 @@ type MemoryManager struct {
// aioManager keeps track of AIOContexts used for async IOs. AIOManager
// must be cloned when CLONE_VM is used.
aioManager aioManager
+
+ // sleepForActivation indicates whether the task should report to be sleeping
+ // before trying to activate the address space. When set to true, delays in
+ // activation are not reported as stuck tasks by the watchdog.
+ sleepForActivation bool
}
// vma represents a virtual memory area.
diff --git a/pkg/sentry/mm/mm_test.go b/pkg/sentry/mm/mm_test.go
index edacca741..fdc308542 100644
--- a/pkg/sentry/mm/mm_test.go
+++ b/pkg/sentry/mm/mm_test.go
@@ -31,7 +31,7 @@ import (
func testMemoryManager(ctx context.Context) *MemoryManager {
p := platform.FromContext(ctx)
mfp := pgalloc.MemoryFileProviderFromContext(ctx)
- mm := NewMemoryManager(p, mfp)
+ mm := NewMemoryManager(p, mfp, false)
mm.layout = arch.MmapLayout{
MinAddr: p.MinUserAddress(),
MaxAddr: p.MaxUserAddress(),
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-29 11:45:54 +0000