gpio: fix race with the mockingfix/lp-1802581-3

1 files changed, 11 insertions, 0 deletions

diff --git a/interfaces/builtin/gpio.go b/interfaces/builtin/gpio.go
index 766d0ff8c7..2f723d0fff 100644
--- a/interfaces/builtin/gpio.go
+++ b/interfaces/builtin/gpio.go
@@ -23,6 +23,7 @@ import (
	"fmt"
	"os"
	"strconv"
+	"time"
 
	"github.com/snapcore/snapd/interfaces"
	"github.com/snapcore/snapd/interfaces/apparmor"
@@ -117,6 +118,16 @@ func (iface *gpioInterface) AppArmorConnectedPlug(spec *apparmor.Specification,
	return err
	}
	}
+	// give the kernel/mock a bit of time to export the device
+	for i := 0; i < 100; i++ {
+	if osutil.FileExists(path) {
+	break
+	}
+	time.Sleep(100 * time.Millisecond)
+	}
+	if !osutil.FileExists(path) {
+	return fmt.Errorf("%q was not created", path)
+	}
	}
 
	// Entries in /sys/class/gpio for single GPIO's are just symlinks