From owner-svn-src-stable-9@FreeBSD.ORG Mon Jun 25 09:41:48 2012 Return-Path: Delivered-To: svn-src-stable-9@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [69.147.83.52]) by hub.freebsd.org (Postfix) with ESMTP id 65FFF1065680; Mon, 25 Jun 2012 09:41:48 +0000 (UTC) (envelope-from kib@FreeBSD.org) Received: from svn.freebsd.org (svn.freebsd.org [IPv6:2001:4f8:fff6::2c]) by mx1.freebsd.org (Postfix) with ESMTP id 5077C8FC08; Mon, 25 Jun 2012 09:41:48 +0000 (UTC) Received: from svn.freebsd.org (localhost [127.0.0.1]) by svn.freebsd.org (8.14.4/8.14.4) with ESMTP id q5P9fm0L063470; Mon, 25 Jun 2012 09:41:48 GMT (envelope-from kib@svn.freebsd.org) Received: (from kib@localhost) by svn.freebsd.org (8.14.4/8.14.4/Submit) id q5P9fmFS063468; Mon, 25 Jun 2012 09:41:48 GMT (envelope-from kib@svn.freebsd.org) Message-Id: <201206250941.q5P9fmFS063468@svn.freebsd.org> From: Konstantin Belousov Date: Mon, 25 Jun 2012 09:41:48 +0000 (UTC) To: src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-stable@freebsd.org, svn-src-stable-9@freebsd.org X-SVN-Group: stable-9 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Cc: Subject: svn commit: r237559 - stable/9/sys/amd64/amd64 X-BeenThere: svn-src-stable-9@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: SVN commit messages for only the 9-stable src tree List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 25 Jun 2012 09:41:48 -0000 Author: kib Date: Mon Jun 25 09:41:47 2012 New Revision: 237559 URL: http://svn.freebsd.org/changeset/base/237559 Log: MFC r237243: Adjust the fix in r236953, by not generating the signal manually, but performing the return to usermode using full return path. Modified: stable/9/sys/amd64/amd64/trap.c Directory Properties: stable/9/sys/ (props changed) Modified: stable/9/sys/amd64/amd64/trap.c ============================================================================== --- stable/9/sys/amd64/amd64/trap.c Mon Jun 25 08:34:14 2012 (r237558) +++ stable/9/sys/amd64/amd64/trap.c Mon Jun 25 09:41:47 2012 (r237559) @@ -982,16 +982,10 @@ amd64_syscall(struct thread *td, int tra * If the user-supplied value of %rip is not a canonical * address, then some CPUs will trigger a ring 0 #GP during * the sysret instruction. However, the fault handler would - * execute with the user's %gs and %rsp in ring 0 which would - * not be safe. Instead, preemptively kill the thread with a - * SIGBUS. + * execute in ring 0 with the user's %gs and %rsp which would + * not be safe. Instead, use the full return path which + * catches the problem safely. */ - if (td->td_frame->tf_rip >= VM_MAXUSER_ADDRESS) { - ksiginfo_init_trap(&ksi); - ksi.ksi_signo = SIGBUS; - ksi.ksi_code = BUS_OBJERR; - ksi.ksi_trapno = T_PROTFLT; - ksi.ksi_addr = (void *)td->td_frame->tf_rip; - trapsignal(td, &ksi); - } + if (td->td_frame->tf_rip >= VM_MAXUSER_ADDRESS) + set_pcb_flags(td->td_pcb, PCB_FULL_IRET); }