pkg/host: improve KMEMLEAK support

Rewind kmemleak fd before reading it second time,
otherwise we will read truncated reports.

Auto-learn what leak reports we've already seen
and ignore them in future. This is required because
there are some false positives and some fire too frequently.
So now we will hit each leak only once per manager run,
but we still will try to reproduce them.

1 files changed, 11 insertions, 11 deletions

diff --git a/pkg/host/host.go b/pkg/host/host.go
index b23dd9ab2..36c42de65 100644
--- a/pkg/host/host.go
+++ b/pkg/host/host.go
@@ -65,7 +65,7 @@ type Features [numFeatures]Feature
 
 var checkFeature [numFeatures]func() string
 var setupFeature [numFeatures]func() error
-var callbFeature [numFeatures]func()
+var callbFeature [numFeatures]func(leakFrames [][]byte)
 
 func unconditionallyEnabled() string { return "" }
 
@@ -104,11 +104,11 @@ func Check(target *prog.Target) (*Features, error) {
 
 // Setup enables and does any one-time setup for the requested features on the host.
 // Note: this can be called multiple times and must be idempotent.
-func Setup(target *prog.Target, features *Features) (func(), error) {
+func Setup(target *prog.Target, features *Features) (func(leakFrames [][]byte), error) {
 	if target.OS == "akaros" || target.OS == "test" {
 		return nil, nil
 	}
-	var callback func()
+	var callback func([][]byte)
 	for n, setup := range setupFeature {
 		if setup == nil || !features[n].Enabled {
 			continue
@@ -117,15 +117,15 @@ func Setup(target *prog.Target, features *Features) (func(), error) {
 			return nil, err
 		}
 		cb := callbFeature[n]
-		if cb != nil {
-			prev := callback
-			callback = func() {
-				cb()
-				if prev != nil {
-					prev()
-				}
+		if cb == nil {
+			continue
+		}
+		prev := callback
+		callback = func(leakFrames [][]byte) {
+			cb(leakFrames)
+			if prev != nil {
+				prev(leakFrames)
 			}
-
 		}
 	}
 	return callback, nil