kern/92895: em driver watchdog reset's warning suppressed due to small bug in em_watchdog()

[Vladimir Ivanov]

>Number:         92895
>Category:       kern
>Synopsis:       em driver watchdog reset's warning suppressed due to small bug in em_watchdog()
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    freebsd-bugs
>State:          open
>Quarter:        
>Keywords:       
>Date-Required:
>Class:          sw-bug
>Submitter-Id:   current-users
>Arrival-Date:   Mon Feb 06 15:30:07 GMT 2006
>Closed-Date:
>Last-Modified:
>Originator:     Vladimir Ivanov
>Release:        RELENG_5
>Organization:
Yandex LLC
>Environment:
FreeBSD dixi.yandex.net 5.5-PRERELEASE FreeBSD 5.5-PRERELEASE #15: Fri Feb  3 18:34:49 MSK 2006     root at dixi.yandex.net:/usr/obj/usr/src/sys/CORE-RTR-RELENG_5  i386

>Description:
EM driver sometimes resets hardware (under heavy load). But never reports watchdog reset (!).
The problem occured due to small mistake in em_watchdog (see patch)

>How-To-Repeat:

>Fix:
--- if_em.c.orig        Fri Feb  3 17:38:46 2006
+++ if_em.c     Mon Feb  6 18:22:58 2006
@@ -774,7 +774,7 @@ em_watchdog(struct ifnet *ifp)
                return;
        }

-       if (em_check_for_link(&adapter->hw))
+       if (!em_check_for_link(&adapter->hw))
                printf("em%d: watchdog timeout -- resetting\n", adapter->unit);

        ifp->if_flags &= ~IFF_RUNNING;

>Release-Note:
>Audit-Trail:
>Unformatted: