Merge release-20200818.0-146-g2c7df1a9a (automated)

14 files changed, 23 insertions, 44 deletions

diff --git a/pkg/sentry/fsimpl/devpts/root_inode_refs.go b/pkg/sentry/fsimpl/devpts/root_inode_refs.go
index 068ee2f20..b860819f0 100644
--- a/pkg/sentry/fsimpl/devpts/root_inode_refs.go
+++ b/pkg/sentry/fsimpl/devpts/root_inode_refs.go
@@ -1,12 +1,12 @@
 package devpts
 
 import (
-	"runtime"
 	"sync/atomic"
 
 	"fmt"
 	"gvisor.dev/gvisor/pkg/log"
 	refs_vfs1 "gvisor.dev/gvisor/pkg/refs"
+	"runtime"
 )
 
 // ownerType is used to customize logging. Note that we use a pointer to T so
diff --git a/pkg/sentry/fsimpl/fuse/inode_refs.go b/pkg/sentry/fsimpl/fuse/inode_refs.go
index 5d1de6067..646042846 100644
--- a/pkg/sentry/fsimpl/fuse/inode_refs.go
+++ b/pkg/sentry/fsimpl/fuse/inode_refs.go
@@ -1,12 +1,12 @@
 package fuse
 
 import (
-	"runtime"
 	"sync/atomic"
 
 	"fmt"
 	"gvisor.dev/gvisor/pkg/log"
 	refs_vfs1 "gvisor.dev/gvisor/pkg/refs"
+	"runtime"
 )
 
 // ownerType is used to customize logging. Note that we use a pointer to T so
diff --git a/pkg/sentry/fsimpl/gofer/gofer.go b/pkg/sentry/fsimpl/gofer/gofer.go
index fa4e19113..0e21c31a4 100644
--- a/pkg/sentry/fsimpl/gofer/gofer.go
+++ b/pkg/sentry/fsimpl/gofer/gofer.go
@@ -195,11 +195,7 @@ const (
 	// and consistent with Linux's semantics (in particular, it is not always
 	// possible for clients to set arbitrary atimes and mtimes depending on the
 	// remote filesystem implementation, and never possible for clients to set
-	// arbitrary ctimes.) If a dentry containing a client-defined atime or
-	// mtime is evicted from cache, client timestamps will be sent to the
-	// remote filesystem on a best-effort basis to attempt to ensure that
-	// timestamps will be preserved when another dentry representing the same
-	// file is instantiated.
+	// arbitrary ctimes.)
 	InteropModeExclusive InteropMode = iota
 
 	// InteropModeWritethrough is appropriate when there are read-only users of
@@ -1315,32 +1311,15 @@ func (d *dentry) destroyLocked(ctx context.Context) {
 	d.handleMu.Unlock()
 
 	if !d.file.isNil() {
-		valid := p9.SetAttrMask{}
-		attr := p9.SetAttr{}
-		if !d.isDeleted() {
-			// Write dirty timestamps back to the remote filesystem.
-			if atomic.LoadUint32(&d.atimeDirty) != 0 {
-				valid.ATime = true
-				valid.ATimeNotSystemTime = true
-				atime := atomic.LoadInt64(&d.atime)
-				attr.ATimeSeconds = uint64(atime / 1e9)
-				attr.ATimeNanoSeconds = uint64(atime % 1e9)
-			}
-			if atomic.LoadUint32(&d.mtimeDirty) != 0 {
-				valid.MTime = true
-				valid.MTimeNotSystemTime = true
-				mtime := atomic.LoadInt64(&d.mtime)
-				attr.MTimeSeconds = uint64(mtime / 1e9)
-				attr.MTimeNanoSeconds = uint64(mtime % 1e9)
-			}
-		}
-
-		// Check if attributes need to be changed before closing the file.
-		if valid.ATime || valid.MTime {
-			if err := d.file.setAttrClose(ctx, valid, attr); err != nil {
-				log.Warningf("gofer.dentry.destroyLocked: failed to close file with write dirty timestamps: %v", err)
-			}
-		} else if err := d.file.close(ctx); err != nil {
+		// Note that it's possible that d.atimeDirty or d.mtimeDirty are true,
+		// i.e. client and server timestamps may differ (because e.g. a client
+		// write was serviced by the page cache, and only written back to the
+		// remote file later). Ideally, we'd write client timestamps back to
+		// the remote filesystem so that timestamps for a new dentry
+		// instantiated for the same file would remain coherent. Unfortunately,
+		// this turns out to be too expensive in many cases, so for now we
+		// don't do this.
+		if err := d.file.close(ctx); err != nil {
 			log.Warningf("gofer.dentry.destroyLocked: failed to close file: %v", err)
 		}
 		d.file = p9file{}
diff --git a/pkg/sentry/fsimpl/host/connected_endpoint_refs.go b/pkg/sentry/fsimpl/host/connected_endpoint_refs.go
index abf4a9082..670166c76 100644
--- a/pkg/sentry/fsimpl/host/connected_endpoint_refs.go
+++ b/pkg/sentry/fsimpl/host/connected_endpoint_refs.go
@@ -1,12 +1,12 @@
 package host
 
 import (
-	"runtime"
 	"sync/atomic"
 
 	"fmt"
 	"gvisor.dev/gvisor/pkg/log"
 	refs_vfs1 "gvisor.dev/gvisor/pkg/refs"
+	"runtime"
 )
 
 // ownerType is used to customize logging. Note that we use a pointer to T so
diff --git a/pkg/sentry/fsimpl/host/inode_refs.go b/pkg/sentry/fsimpl/host/inode_refs.go
index 75b9f49e2..49c57c113 100644
--- a/pkg/sentry/fsimpl/host/inode_refs.go
+++ b/pkg/sentry/fsimpl/host/inode_refs.go
@@ -1,12 +1,12 @@
 package host
 
 import (
-	"runtime"
 	"sync/atomic"
 
 	"fmt"
 	"gvisor.dev/gvisor/pkg/log"
 	refs_vfs1 "gvisor.dev/gvisor/pkg/refs"
+	"runtime"
 )
 
 // ownerType is used to customize logging. Note that we use a pointer to T so
diff --git a/pkg/sentry/fsimpl/kernfs/dentry_refs.go b/pkg/sentry/fsimpl/kernfs/dentry_refs.go
index b7125caee..0269851c9 100644
--- a/pkg/sentry/fsimpl/kernfs/dentry_refs.go
+++ b/pkg/sentry/fsimpl/kernfs/dentry_refs.go
@@ -1,12 +1,12 @@
 package kernfs
 
 import (
-	"runtime"
 	"sync/atomic"
 
 	"fmt"
 	"gvisor.dev/gvisor/pkg/log"
 	refs_vfs1 "gvisor.dev/gvisor/pkg/refs"
+	"runtime"
 )
 
 // ownerType is used to customize logging. Note that we use a pointer to T so
diff --git a/pkg/sentry/fsimpl/kernfs/static_directory_refs.go b/pkg/sentry/fsimpl/kernfs/static_directory_refs.go
index 0ff013c97..866620ef9 100644
--- a/pkg/sentry/fsimpl/kernfs/static_directory_refs.go
+++ b/pkg/sentry/fsimpl/kernfs/static_directory_refs.go
@@ -1,12 +1,12 @@
 package kernfs
 
 import (
-	"runtime"
 	"sync/atomic"
 
 	"fmt"
 	"gvisor.dev/gvisor/pkg/log"
 	refs_vfs1 "gvisor.dev/gvisor/pkg/refs"
+	"runtime"
 )
 
 // ownerType is used to customize logging. Note that we use a pointer to T so
diff --git a/pkg/sentry/fsimpl/proc/fd_dir_inode_refs.go b/pkg/sentry/fsimpl/proc/fd_dir_inode_refs.go
index 454862d98..84c03e6cd 100644
--- a/pkg/sentry/fsimpl/proc/fd_dir_inode_refs.go
+++ b/pkg/sentry/fsimpl/proc/fd_dir_inode_refs.go
@@ -1,12 +1,12 @@
 package proc
 
 import (
-	"runtime"
 	"sync/atomic"
 
 	"fmt"
 	"gvisor.dev/gvisor/pkg/log"
 	refs_vfs1 "gvisor.dev/gvisor/pkg/refs"
+	"runtime"
 )
 
 // ownerType is used to customize logging. Note that we use a pointer to T so
diff --git a/pkg/sentry/fsimpl/proc/fd_info_dir_inode_refs.go b/pkg/sentry/fsimpl/proc/fd_info_dir_inode_refs.go
index d2169be5b..5b3c7cd1c 100644
--- a/pkg/sentry/fsimpl/proc/fd_info_dir_inode_refs.go
+++ b/pkg/sentry/fsimpl/proc/fd_info_dir_inode_refs.go
@@ -1,12 +1,12 @@
 package proc
 
 import (
-	"runtime"
 	"sync/atomic"
 
 	"fmt"
 	"gvisor.dev/gvisor/pkg/log"
 	refs_vfs1 "gvisor.dev/gvisor/pkg/refs"
+	"runtime"
 )
 
 // ownerType is used to customize logging. Note that we use a pointer to T so
diff --git a/pkg/sentry/fsimpl/proc/subtasks_inode_refs.go b/pkg/sentry/fsimpl/proc/subtasks_inode_refs.go
index 9b50f632c..3091deb89 100644
--- a/pkg/sentry/fsimpl/proc/subtasks_inode_refs.go
+++ b/pkg/sentry/fsimpl/proc/subtasks_inode_refs.go
@@ -1,12 +1,12 @@
 package proc
 
 import (
-	"runtime"
 	"sync/atomic"
 
 	"fmt"
 	"gvisor.dev/gvisor/pkg/log"
 	refs_vfs1 "gvisor.dev/gvisor/pkg/refs"
+	"runtime"
 )
 
 // ownerType is used to customize logging. Note that we use a pointer to T so
diff --git a/pkg/sentry/fsimpl/proc/task_inode_refs.go b/pkg/sentry/fsimpl/proc/task_inode_refs.go
index c29272f9b..5833527c5 100644
--- a/pkg/sentry/fsimpl/proc/task_inode_refs.go
+++ b/pkg/sentry/fsimpl/proc/task_inode_refs.go
@@ -1,12 +1,12 @@
 package proc
 
 import (
-	"runtime"
 	"sync/atomic"
 
 	"fmt"
 	"gvisor.dev/gvisor/pkg/log"
 	refs_vfs1 "gvisor.dev/gvisor/pkg/refs"
+	"runtime"
 )
 
 // ownerType is used to customize logging. Note that we use a pointer to T so
diff --git a/pkg/sentry/fsimpl/proc/tasks_inode_refs.go b/pkg/sentry/fsimpl/proc/tasks_inode_refs.go
index 7e0b70f6c..0961dd629 100644
--- a/pkg/sentry/fsimpl/proc/tasks_inode_refs.go
+++ b/pkg/sentry/fsimpl/proc/tasks_inode_refs.go
@@ -1,12 +1,12 @@
 package proc
 
 import (
-	"runtime"
 	"sync/atomic"
 
 	"fmt"
 	"gvisor.dev/gvisor/pkg/log"
 	refs_vfs1 "gvisor.dev/gvisor/pkg/refs"
+	"runtime"
 )
 
 // ownerType is used to customize logging. Note that we use a pointer to T so
diff --git a/pkg/sentry/fsimpl/sys/dir_refs.go b/pkg/sentry/fsimpl/sys/dir_refs.go
index d42edb20e..718d542eb 100644
--- a/pkg/sentry/fsimpl/sys/dir_refs.go
+++ b/pkg/sentry/fsimpl/sys/dir_refs.go
@@ -1,12 +1,12 @@
 package sys
 
 import (
-	"runtime"
 	"sync/atomic"
 
 	"fmt"
 	"gvisor.dev/gvisor/pkg/log"
 	refs_vfs1 "gvisor.dev/gvisor/pkg/refs"
+	"runtime"
 )
 
 // ownerType is used to customize logging. Note that we use a pointer to T so
diff --git a/pkg/sentry/fsimpl/tmpfs/inode_refs.go b/pkg/sentry/fsimpl/tmpfs/inode_refs.go
index 4f4037adb..5ec208d9e 100644
--- a/pkg/sentry/fsimpl/tmpfs/inode_refs.go
+++ b/pkg/sentry/fsimpl/tmpfs/inode_refs.go
@@ -1,12 +1,12 @@
 package tmpfs
 
 import (
-	"runtime"
 	"sync/atomic"
 
 	"fmt"
 	"gvisor.dev/gvisor/pkg/log"
 	refs_vfs1 "gvisor.dev/gvisor/pkg/refs"
+	"runtime"
 )
 
 // ownerType is used to customize logging. Note that we use a pointer to T so