From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from sc8-sf-mx1-b.sourceforge.net ([10.3.1.11] helo=sc8-sf-mx1.sourceforge.net) by sc8-sf-list1.sourceforge.net with esmtp (Exim 4.30) id 1CWgxv-0005sx-2l for user-mode-linux-devel@lists.sourceforge.net; Tue, 23 Nov 2004 12:08:43 -0800 Received: from smtp002.mail.ukl.yahoo.com ([217.12.11.33]) by sc8-sf-mx1.sourceforge.net with smtp (Exim 4.41) id 1CWgxt-0001XB-6r for user-mode-linux-devel@lists.sourceforge.net; Tue, 23 Nov 2004 12:08:42 -0800 From: Blaisorblade Subject: Re: [uml-devel] Re: The current fix-kill patch References: <200411230550.iAN5o8mY007302@ccure.user-mode-linux.org> <41A352E4.5050607@fujitsu-siemens.com> In-Reply-To: <41A352E4.5050607@fujitsu-siemens.com> MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Content-Disposition: inline Message-Id: <200411232110.51937.blaisorblade_spam@yahoo.it> Sender: user-mode-linux-devel-admin@lists.sourceforge.net Errors-To: user-mode-linux-devel-admin@lists.sourceforge.net List-Unsubscribe: , List-Id: The user-mode Linux development list List-Post: List-Help: List-Subscribe: , List-Archive: Date: Tue, 23 Nov 2004 21:10:51 +0100 To: user-mode-linux-devel@lists.sourceforge.net Cc: Bodo Stroesser , Jeff Dike On Tuesday 23 November 2004 16:10, Bodo Stroesser wrote: > Jeff Dike wrote: > > Here's the latest fix-kill patch in my tree. Please test and report... > Have tested based on 2.6.9-bb3. I removed "rework-uml-hang-on-2.6.9-host", > added BlaisorBlade's "uml-hang-on-2.6.9-host", and adapted iand added this > new patch. Btw, if you send another patch, send it relative to "uml-hang-on-2.6.9-host", or to it + fix-kill from Jeff, so I can easily spot the differences. This is a general rule, also (with a bit of taste, i.e. applies between developers, not between users). > The resulting UML kernel for me works fine on host > 2.6.7-skas3-v7 and 2.6.9-skas3-v7. Not yet tested this Jeff Dike's one. However, for me, on a 2.6.10-rc2 SKAS patched host (with the update I posted here and on my site to make SKAS compile), UML hangs on shutdown in SKAS mode. Nobody else reported this with -bb3, so I suppose there is something new in 2.6.10-rc2 (I didn't yet test this with Please let's start testing it ASAP, so that it's fixed before 2.6.10 release. However, I have at least to apply the Jeff's fix before. > Next, I tested what happens if the "kill(pid, SIGKILL);" and > "ptrace(PTRACE_CONT, pid);" are removed from os_kill_ptraced_process(), and > it also worked fine. > Since PTRACE_KILL wakes up the ptraced process unconditionally, IMHO > "ptrace(PTRACE_CONT, pid);" has no effect here. You reported PTRACE_KILL not to work in some Ptrace states. PTRACE_CONT is intended to fix this (even if PTRACE_KILL is not needed). > And "kill(pid, SIGKILL);" > only is needed, if the ptraced process is not stopped on a > ptrace-interception. Well, PTRACE_CONT is to resume if from the ptrace-interception. Let's start by distinguishing bugs (i.e. reggressions in 2.6.9 behaviour vs. 2.6.8 and earlier one) from strange APIs. Gdb, or any ptracer, is IMHO never supposed to SIGKILL the process directly. > Since os_kill_ptraced_process() is called only then, > when the ptraced process is known to be on a ptrace-stop, I would like to > remove "kill(pid, SIGKILL);", too. > os_kill_ptraced_process() is called each time, a process in TT exec()s. > Thus avoiding unneeded calls is a little speedup. -- Paolo Giarrusso, aka Blaisorblade Linux registered user n. 292729 http://www.user-mode-linux.org/~blaisorblade ------------------------------------------------------- SF email is sponsored by - The IT Product Guide Read honest & candid reviews on hundreds of IT Products from real users. Discover which products truly live up to the hype. Start reading now. http://productguide.itmanagersjournal.com/ _______________________________________________ User-mode-linux-devel mailing list User-mode-linux-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/user-mode-linux-devel