From owner-svn-src-all@freebsd.org Fri Nov 30 15:52:04 2018 Return-Path: Delivered-To: svn-src-all@mailman.ysv.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mailman.ysv.freebsd.org (Postfix) with ESMTP id A7431114772B; Fri, 30 Nov 2018 15:52:04 +0000 (UTC) (envelope-from trasz@FreeBSD.org) Received: from mxrelay.nyi.freebsd.org (mxrelay.nyi.freebsd.org [IPv6:2610:1c1:1:606c::19:3]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client CN "mxrelay.nyi.freebsd.org", Issuer "Let's Encrypt Authority X3" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 518528725E; Fri, 30 Nov 2018 15:52:04 +0000 (UTC) (envelope-from trasz@FreeBSD.org) Received: from repo.freebsd.org (repo.freebsd.org [IPv6:2610:1c1:1:6068::e6a:0]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client did not present a certificate) by mxrelay.nyi.freebsd.org (Postfix) with ESMTPS id 322142A77; Fri, 30 Nov 2018 15:52:04 +0000 (UTC) (envelope-from trasz@FreeBSD.org) Received: from repo.freebsd.org ([127.0.1.37]) by repo.freebsd.org (8.15.2/8.15.2) with ESMTP id wAUFq4lq058962; Fri, 30 Nov 2018 15:52:04 GMT (envelope-from trasz@FreeBSD.org) Received: (from trasz@localhost) by repo.freebsd.org (8.15.2/8.15.2/Submit) id wAUFq40O058961; Fri, 30 Nov 2018 15:52:04 GMT (envelope-from trasz@FreeBSD.org) Message-Id: <201811301552.wAUFq40O058961@repo.freebsd.org> X-Authentication-Warning: repo.freebsd.org: trasz set sender to trasz@FreeBSD.org using -f From: Edward Tomasz Napierala Date: Fri, 30 Nov 2018 15:52:04 +0000 (UTC) To: src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-head@freebsd.org Subject: svn commit: r341342 - head/share/man/man4 X-SVN-Group: head X-SVN-Commit-Author: trasz X-SVN-Commit-Paths: head/share/man/man4 X-SVN-Commit-Revision: 341342 X-SVN-Commit-Repository: base MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-Rspamd-Queue-Id: 518528725E X-Spamd-Result: default: False [0.80 / 15.00]; local_wl_from(0.00)[FreeBSD.org]; NEURAL_SPAM_LONG(0.31)[0.307,0]; NEURAL_SPAM_MEDIUM(0.26)[0.256,0]; ASN(0.00)[asn:11403, ipnet:2610:1c1:1::/48, country:US]; NEURAL_SPAM_SHORT(0.24)[0.241,0] X-Rspamd-Server: mx1.freebsd.org X-BeenThere: svn-src-all@freebsd.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: "SVN commit messages for the entire src tree \(except for " user" and " projects" \)" List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 30 Nov 2018 15:52:04 -0000 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