From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S262495AbULCTdd (ORCPT ); Fri, 3 Dec 2004 14:33:33 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S262486AbULCTcw (ORCPT ); Fri, 3 Dec 2004 14:32:52 -0500 Received: from pool-151-203-6-248.bos.east.verizon.net ([151.203.6.248]:25604 "EHLO ccure.user-mode-linux.org") by vger.kernel.org with ESMTP id S262487AbULCTaC (ORCPT ); Fri, 3 Dec 2004 14:30:02 -0500 Message-Id: <200412032146.iB3Lk3ZW004730@ccure.user-mode-linux.org> X-Mailer: exmh version 2.4 06/23/2000 with nmh-1.1-RC1 To: akpm@osdl.org cc: linux-kernel@vger.kernel.org, Blaisorblade , Bodo Stroesser Subject: [PATCH] UML - use SYSEMU_SINGLESTEP Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Date: Fri, 03 Dec 2004 16:46:03 -0500 From: Jeff Dike Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org This implements using the new ptrace option SYSEMU_SINGLESTEP in UML (advanced sysemu) in SKAS and TT modes. To have a fast selection of the appropriate ptrace option to use next, a 2 dimensional arry is used and singlestepping() is modified to return 0,1 or 2: 0 = don't do singlestepping 1 = singlestep a syscall 2 = singlestep a "non syscall" instruction In do_syscall() writing of the syscall number is supressed, if the advanced sysemu is in use (that does it itself). Signed-off-by: Bodo Stroesser Signed-off-by: Jeff Dike Index: 2.6.9/arch/um/include/ptrace_user.h =================================================================== --- 2.6.9.orig/arch/um/include/ptrace_user.h 2004-12-01 23:54:59.000000000 -0500 +++ 2.6.9/arch/um/include/ptrace_user.h 2004-12-01 23:55:20.000000000 -0500 @@ -29,4 +29,11 @@ int get_using_sysemu(void); extern int sysemu_supported; +#define SELECT_PTRACE_OPERATION(sysemu_mode, singlestep_mode) \ + (((int[3][3] ) { \ + { PTRACE_SYSCALL, PTRACE_SYSCALL, PTRACE_SINGLESTEP }, \ + { PTRACE_SYSEMU, PTRACE_SYSEMU, PTRACE_SINGLESTEP }, \ + { PTRACE_SYSEMU, PTRACE_SYSEMU_SINGLESTEP, PTRACE_SYSEMU_SINGLESTEP }}) \ + [sysemu_mode][singlestep_mode]) + #endif Index: 2.6.9/arch/um/kernel/process_kern.c =================================================================== --- 2.6.9.orig/arch/um/kernel/process_kern.c 2004-12-01 23:54:59.000000000 -0500 +++ 2.6.9/arch/um/kernel/process_kern.c 2004-12-01 23:55:20.000000000 -0500 @@ -464,9 +464,9 @@ return(0); if (task->thread.singlestep_syscall) - return(0); + return(1); - return 1; + return 2; } /* Index: 2.6.9/arch/um/kernel/skas/process.c =================================================================== --- 2.6.9.orig/arch/um/kernel/skas/process.c 2004-12-01 23:51:51.000000000 -0500 +++ 2.6.9/arch/um/kernel/skas/process.c 2004-12-01 23:56:25.000000000 -0500 @@ -140,15 +140,15 @@ void userspace(union uml_pt_regs *regs) { - int err, status, op, pt_syscall_parm, pid = userspace_pid[0]; + int err, status, op, pid = userspace_pid[0]; int local_using_sysemu; /*To prevent races if using_sysemu changes under us.*/ restore_registers(regs); local_using_sysemu = get_using_sysemu(); - pt_syscall_parm = local_using_sysemu ? PTRACE_SYSEMU : PTRACE_SYSCALL; - err = ptrace(pt_syscall_parm, pid, 0, 0); + op = local_using_sysemu ? PTRACE_SYSEMU : PTRACE_SYSCALL; + err = ptrace(op, pid, 0, 0); if(err) panic("userspace - PTRACE_%s failed, errno = %d\n", @@ -196,10 +196,8 @@ /*Now we ended the syscall, so re-read local_using_sysemu.*/ local_using_sysemu = get_using_sysemu(); - pt_syscall_parm = local_using_sysemu ? PTRACE_SYSEMU : PTRACE_SYSCALL; - op = singlestepping(NULL) ? PTRACE_SINGLESTEP : - pt_syscall_parm; + op = SELECT_PTRACE_OPERATION(local_using_sysemu, singlestepping(NULL)); err = ptrace(op, pid, 0, 0); if(err) Index: 2.6.9/arch/um/kernel/tt/syscall_user.c =================================================================== --- 2.6.9.orig/arch/um/kernel/tt/syscall_user.c 2004-12-01 23:53:37.000000000 -0500 +++ 2.6.9/arch/um/kernel/tt/syscall_user.c 2004-12-01 23:55:20.000000000 -0500 @@ -62,6 +62,10 @@ ((unsigned long *) PT_IP(proc_regs) <= &_etext)) tracer_panic("I'm tracing myself and I can't get out"); + /* advanced sysemu mode set syscall number to -1 automatically */ + if (local_using_sysemu==2) + return; + /* syscall number -1 in sysemu skips syscall restarting in host */ if(ptrace(PTRACE_POKEUSER, pid, PT_SYSCALL_NR_OFFSET, local_using_sysemu ? -1 : __NR_getpid) < 0) Index: 2.6.9/arch/um/kernel/tt/tracer.c =================================================================== --- 2.6.9.orig/arch/um/kernel/tt/tracer.c 2004-12-01 23:53:37.000000000 -0500 +++ 2.6.9/arch/um/kernel/tt/tracer.c 2004-12-01 23:55:20.000000000 -0500 @@ -186,7 +186,7 @@ unsigned long eip = 0; int status, pid = 0, sig = 0, cont_type, tracing = 0, op = 0; int last_index, proc_id = 0, n, err, old_tracing = 0, strace = 0; - int pt_syscall_parm, local_using_sysemu = 0; + int local_using_sysemu = 0; signal(SIGPIPE, SIG_IGN); setup_tracer_winch(); @@ -391,18 +391,14 @@ } local_using_sysemu = get_using_sysemu(); - pt_syscall_parm = local_using_sysemu ? PTRACE_SYSEMU : PTRACE_SYSCALL; - if(tracing){ - if(singlestepping(task)) - cont_type = PTRACE_SINGLESTEP; - else cont_type = pt_syscall_parm; - } - else cont_type = PTRACE_CONT; - - if((cont_type == PTRACE_CONT) && - (debugger_pid != -1) && strace) + if(tracing) + cont_type = SELECT_PTRACE_OPERATION(local_using_sysemu, + singlestepping(task)); + else if((debugger_pid != -1) && strace) cont_type = PTRACE_SYSCALL; + else + cont_type = PTRACE_CONT; if(ptrace(cont_type, pid, 0, sig) != 0){ tracer_panic("ptrace failed to continue "