From owner-svn-src-head@freebsd.org  Fri Oct  9 20:20:43 2020
Return-Path: <owner-svn-src-head@freebsd.org>
Delivered-To: svn-src-head@mailman.nyi.freebsd.org
Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1])
 by mailman.nyi.freebsd.org (Postfix) with ESMTP id 5E9A742C08C;
 Fri,  9 Oct 2020 20:20:43 +0000 (UTC) (envelope-from jhb@FreeBSD.org)
Received: from mxrelay.nyi.freebsd.org (mxrelay.nyi.freebsd.org
 [IPv6:2610:1c1:1:606c::19:3])
 (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits)
 key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256
 client-signature RSA-PSS (4096 bits) client-digest SHA256)
 (Client CN "mxrelay.nyi.freebsd.org",
 Issuer "Let's Encrypt Authority X3" (verified OK))
 by mx1.freebsd.org (Postfix) with ESMTPS id 4C7KFl1tPwz4qCS;
 Fri,  9 Oct 2020 20:20:43 +0000 (UTC) (envelope-from jhb@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 1FC301EF58;
 Fri,  9 Oct 2020 20:20:43 +0000 (UTC) (envelope-from jhb@FreeBSD.org)
Received: from repo.freebsd.org ([127.0.1.37])
 by repo.freebsd.org (8.15.2/8.15.2) with ESMTP id 099KKhOP030800;
 Fri, 9 Oct 2020 20:20:43 GMT (envelope-from jhb@FreeBSD.org)
Received: (from jhb@localhost)
 by repo.freebsd.org (8.15.2/8.15.2/Submit) id 099KKgPM030799;
 Fri, 9 Oct 2020 20:20:42 GMT (envelope-from jhb@FreeBSD.org)
Message-Id: <202010092020.099KKgPM030799@repo.freebsd.org>
X-Authentication-Warning: repo.freebsd.org: jhb set sender to jhb@FreeBSD.org
 using -f
From: John Baldwin <jhb@FreeBSD.org>
Date: Fri, 9 Oct 2020 20:20:42 +0000 (UTC)
To: src-committers@freebsd.org, svn-src-all@freebsd.org,
 svn-src-head@freebsd.org
Subject: svn commit: r366584 - head/sys/kern
X-SVN-Group: head
X-SVN-Commit-Author: jhb
X-SVN-Commit-Paths: head/sys/kern
X-SVN-Commit-Revision: 366584
X-SVN-Commit-Repository: base
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
X-BeenThere: svn-src-head@freebsd.org
X-Mailman-Version: 2.1.33
Precedence: list
List-Id: SVN commit messages for the src tree for head/-current
 <svn-src-head.freebsd.org>
List-Unsubscribe: <https://lists.freebsd.org/mailman/options/svn-src-head>,
 <mailto:svn-src-head-request@freebsd.org?subject=unsubscribe>
List-Archive: <http://lists.freebsd.org/pipermail/svn-src-head/>
List-Post: <mailto:svn-src-head@freebsd.org>
List-Help: <mailto:svn-src-head-request@freebsd.org?subject=help>
List-Subscribe: <https://lists.freebsd.org/mailman/listinfo/svn-src-head>,
 <mailto:svn-src-head-request@freebsd.org?subject=subscribe>
X-List-Received-Date: Fri, 09 Oct 2020 20:20:43 -0000

Author: jhb
Date: Fri Oct  9 20:20:42 2020
New Revision: 366584
URL: https://svnweb.freebsd.org/changeset/base/366584

Log:
  Don't invoke semunload() if seminit() fails during MOD_LOAD.
  
  The module handler code invokes a MOD_UNLOAD event immediately if
  MOD_LOAD fails.  The result was that if seminit() failed, semunload()
  was invoked twice.  semunload() is not idempotent however and would
  try to remove it's process_exit eventhandler twice resulting in a
  panic.
  
  Reviewed by:	kib, markj
  Obtained from:	CheriBSD
  MFC after:	1 month
  Sponsored by:	DARPA
  Differential Revision:	https://reviews.freebsd.org/D26696

Modified:
  head/sys/kern/sysv_sem.c

Modified: head/sys/kern/sysv_sem.c
==============================================================================
--- head/sys/kern/sysv_sem.c	Fri Oct  9 19:12:44 2020	(r366583)
+++ head/sys/kern/sysv_sem.c	Fri Oct  9 20:20:42 2020	(r366584)
@@ -381,8 +381,6 @@ sysvsem_modload(struct module *module, int cmd, void *
 	switch (cmd) {
 	case MOD_LOAD:
 		error = seminit();
-		if (error != 0)
-			semunload();
 		break;
 	case MOD_UNLOAD:
 		error = semunload();