[multipathd] fix offline devices reported as active

multipathd(8) continues calling reinstate_path() in checkerloop(),
if multipathd(8) is started on the system which has multipath maps
including offline devices.
The reason is pp->checkfn() returns -1 for offline devices and
pp->state of these paths are 1.
(I'm using "echo offline > /sys/block/sd?/device/state" for the testing.)

As a result, multipathd(8) makes offline devices active state.
And this behavior also affects the no_path_retry feature, since
struct multipath.nr_active is incremented in reinstate_path().

The following patch fixes this problem.
If the return value from pp->checkfn is -1, the path isn't available.
So I think that we can ignore it.

Kiyoshi Ueda, NEC

diff --git a/multipathd/main.c b/multipathd/main.c
index 4275a37..f23a98e 100644 (file)
--- a/multipathd/main.c
+++ b/multipathd/main.c
@@ -1240,6 +1240,12 @@ checkerloop (void *ap)
                        newstate = pp->checkfn(pp->fd, checker_msg,
                                               &pp->checker_context);
                        
+                       if (newstate < 0) {
+                               condlog(2, "%s: unusable path", pp->dev);
+                               pathinfo(pp, conf->hwtable, 0);
+                               continue;
+                       }
+
                        if (newstate != pp->state) {
                                pp->state = newstate;
                                LOG_MSG(1, checker_msg);