From owner-svn-src-head@freebsd.org Thu May 11 17:03:46 2017 Return-Path: Delivered-To: svn-src-head@mailman.ysv.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) by mailman.ysv.freebsd.org (Postfix) with ESMTP id 8AC54D680C0; Thu, 11 May 2017 17:03:46 +0000 (UTC) (envelope-from markj@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 mx1.freebsd.org (Postfix) with ESMTPS id 5CDCBF98; Thu, 11 May 2017 17:03:46 +0000 (UTC) (envelope-from markj@FreeBSD.org) Received: from repo.freebsd.org ([127.0.1.37]) by repo.freebsd.org (8.15.2/8.15.2) with ESMTP id v4BH3jTG035619; Thu, 11 May 2017 17:03:45 GMT (envelope-from markj@FreeBSD.org) Received: (from markj@localhost) by repo.freebsd.org (8.15.2/8.15.2/Submit) id v4BH3jVa035618; Thu, 11 May 2017 17:03:45 GMT (envelope-from markj@FreeBSD.org) Message-Id: <201705111703.v4BH3jVa035618@repo.freebsd.org> X-Authentication-Warning: repo.freebsd.org: markj set sender to markj@FreeBSD.org using -f From: Mark Johnston Date: Thu, 11 May 2017 17:03:45 +0000 (UTC) To: src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-head@freebsd.org Subject: svn commit: r318191 - head/sys/kern X-SVN-Group: head 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: 2.1.23 Precedence: list List-Id: SVN commit messages for the src tree for head/-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 11 May 2017 17:03:46 -0000 Author: markj Date: Thu May 11 17:03:45 2017 New Revision: 318191 URL: https://svnweb.freebsd.org/changeset/base/318191 Log: Let ptracestop() suspend threads sleeping in an SBDRY section. When a thread enters ptracestop(), for example because it had received SIGSTOP from ptrace(PT_ATTACH), it attempts to suspend other threads in the same process. In the case of a thread sleeping interruptibly in an SBDRY section, sig_suspend_threads() must wake the thread and allow it to reach the user-mode boundary. However, sig_suspend_threads() would erroneously avoid waking up such threads, resulting in an apparent hang. Reviewed by: kib Tested by: pho MFC after: 2 weeks Sponsored by: Dell EMC Isilon Modified: head/sys/kern/kern_sig.c Modified: head/sys/kern/kern_sig.c ============================================================================== --- head/sys/kern/kern_sig.c Thu May 11 16:37:29 2017 (r318190) +++ head/sys/kern/kern_sig.c Thu May 11 17:03:45 2017 (r318191) @@ -2477,6 +2477,7 @@ sig_suspend_threads(struct thread *td, s PROC_LOCK_ASSERT(p, MA_OWNED); PROC_SLOCK_ASSERT(p, MA_OWNED); + MPASS(sending || td == curthread); wakeup_swapper = 0; FOREACH_THREAD_IN_PROC(p, td2) { @@ -2493,10 +2494,9 @@ sig_suspend_threads(struct thread *td, s */ KASSERT(!TD_IS_SUSPENDED(td2), ("thread with deferred stops suspended")); - if (TD_SBDRY_INTR(td2) && sending) { + if (TD_SBDRY_INTR(td2)) wakeup_swapper |= sleepq_abort(td2, TD_SBDRY_ERRNO(td2)); - } } else if (!TD_IS_SUSPENDED(td2)) { thread_suspend_one(td2); }