Author: trasz Date: Fri Nov 30 15:52:03 2018 New Revision: 341342 URL: https://svnweb.freebsd.org/changeset/base/341342
Log: Revert r341337; according to imp@ we still support these. MFC after: 2 weeks Sponsored by: DARPA, AFRL Modified: head/share/man/man4/ddb.4 Modified: head/share/man/man4/ddb.4 ============================================================================== --- head/share/man/man4/ddb.4 Fri Nov 30 12:17:35 2018 (r341341) +++ head/share/man/man4/ddb.4 Fri Nov 30 15:52:03 2018 (r341342) @@ -1491,8 +1491,17 @@ might be defined to have special handling, and might be defined to simply panic and reboot. .El .Sh HINTS +On machines with an ISA expansion bus, a simple NMI generation card can be +constructed by connecting a push button between the A01 and B01 (CHCHK# and +GND) card fingers. +Momentarily shorting these two fingers together may cause the bridge chipset to +generate an NMI, which causes the kernel to pass control to +.Nm . +Some bridge chipsets do not generate a NMI on CHCHK#, so your mileage may vary. The NMI allows one to break into the debugger on a wedged machine to diagnose problems. +Other bus' bridge chipsets may be able to generate NMI using bus specific +methods. There are many PCI and PCIe add-in cards which can generate NMI for debugging. Modern server systems typically use IPMI to generate signals to enter the _______________________________________________ svn-src-head@freebsd.org mailing list https://lists.freebsd.org/mailman/listinfo/svn-src-head To unsubscribe, send any mail to "svn-src-head-unsubscr...@freebsd.org"
