Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S261704AbTEKP2u (ORCPT ); Sun, 11 May 2003 11:28:50 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S261706AbTEKP2u (ORCPT ); Sun, 11 May 2003 11:28:50 -0400 Received: from siaag2ac.compuserve.com ([149.174.40.133]:62404 "EHLO siaag2ac.compuserve.com") by vger.kernel.org with ESMTP id S261704AbTEKP2s (ORCPT ); Sun, 11 May 2003 11:28:48 -0400 Date: Sun, 11 May 2003 11:37:17 -0400 From: Chuck Ebbert <76306.1226@compuserve.com> Subject: Re: Problem: strace -ff fails on 2.4.21-rc1 To: Carl-Daniel Hailfinger Cc: linux-kernel , Ingo Oeser , Alan Cox Message-ID: <200305111140_MC3-1-385D-EEF@compuserve.com> MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3489 Lines: 99 Carl-Daniel Hailfinger wrote: > Chuck Ebbert wrote: > > I just found out minicom is spawing /sbin/lockdev which is setgrp > > 'lock'. Would that cause ptrace failure?? > > AFAIK that could have caused the failure. Please test 2.4.21-rc2 whcih > has fixes for many ptrace problems. I can now strace minicom and its children with 2.4.21-rc2-ac1 but it hangs on exit. Both child processes exit successfully: # tail -5 minicom.trc.5775 10:16:49.299253 kill(5774, SIG_0) = 0 10:16:49.299418 unlink("/var/lock/LOCKDEV") = 0 10:16:49.299649 close(3) = 0 10:16:49.299849 umask(022) = 02 10:16:49.300043 _exit(0) = ? # tail -8 minicom.trc.5776 10:17:05.497676 kill(5774, SIG_0) = 0 10:17:05.497845 unlink("/var/lock/LCK...5774") = 0 10:17:05.498068 unlink("/var/lock/LCK..ttyS1") = 0 10:17:05.498283 unlink("/var/lock/LCK.004.065") = 0 10:17:05.498616 unlink("/var/lock/LOCKDEV") = 0 10:17:05.498870 close(4) = 0 10:17:05.499065 umask(022) = 02 10:17:05.499337 _exit(0) = ? However strace and minicom are hung up somehow and the screen is black with a blinking cursor at row 1 column 1. The other ttys all work OK and killing minicom cleans everything up. # tail -3 minicom.trc 10:17:05.499678 --- SIGCHLD (Child exited) --- 10:17:05.499760 rt_sigaction(SIGCHLD, {SIG_DFL}, {SIG_IGN}, 8) = 0 10:17:05.499971 close(3 strace S C015FF82 960 5773 822 5774 (NOTLB) Call Trace: [] [] [] minicom S 00000000 2400 5774 5773 (NOTLB) Call Trace: [] [] [] [] [] [] [] [] [] [] [] [] [] Proc; strace >>EIP; c015ff82 <===== Trace; c015ff82 Trace; c011dba8 Trace; c0108b73 Proc; minicom >>EIP; 00000000 Before first symbol Trace; c0122f24 Trace; c0124095 Trace; c021195b Trace; c0220d79 Trace; c020d997 Trace; c0124095 Trace; c0124159 Trace; c020e01a Trace; c013c52e Trace; c01183a1 Trace; c013b1d5 Trace; c013b23b Trace; c0108bdf Configuration: 2.4.21-rc2-ac1 SMP kernel on 1-CPU SMP machine (PII Xeon, 440GX) To reproduce: # strace -ff -q -tt -o minicom.trc minicom Note: I also get lockups while minicom is running: Proc; strace >>EIP; c015ff82 <===== Trace; c015ff82 Trace; c011dba8 Trace; c0108b73 Proc; minicom >>EIP; 00000000 Before first symbol Trace; c0122f24 Trace; c021105a Trace; c020cf5f Trace; c013b706 Trace; c0108bdf - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/