Re: [PATCH 1/2] namespaces: give each namespace a serial number
Quoting Richard Guy Briggs (rgb(a)redhat.com):
Most of this looks reasonable, but I'm curious about something,
+/**
+ * ns_serial - compute a serial number for the namespace
+ *
+ * Compute a serial number for the namespace to uniquely identify it in
+ * audit records.
+ */
+unsigned int ns_serial(void)
+{
+ static DEFINE_SPINLOCK(serial_lock);
+ static unsigned int serial = 4; /* reserved for IPC, UTS, user, PID */
+
+ unsigned long flags;
+ unsigned int ret;
+
+ spin_lock_irqsave(&serial_lock, flags);
+ do {
+ ret = ++serial;
+ } while (unlikely(!ret));
Why exactly are you doing this? Surely if serial is going to
wrap around we've got a bigger problem than just wanting go
bump one more time?
+ spin_unlock_irqrestore(&serial_lock, flags);
+
+ return ret;
+}