From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from sc8-sf-mx2-b.sourceforge.net ([10.3.1.92] helo=mail.sourceforge.net) by sc8-sf-list1.sourceforge.net with esmtp (Exim 4.30) id 1E3d7u-0001Dn-R7 for user-mode-linux-devel@lists.sourceforge.net; Fri, 12 Aug 2005 10:15:26 -0700 Received: from lakshmi.addtoit.com ([198.99.130.6] helo=lakshmi.solana.com) by mail.sourceforge.net with esmtp (Exim 4.44) id 1E3d7u-0005VB-CI for user-mode-linux-devel@lists.sourceforge.net; Fri, 12 Aug 2005 10:15:26 -0700 From: Jeff Dike Message-ID: <20050812170900.GC7448@ccure.user-mode-linux.org> References: <42D7D802.2080100@fujitsu-siemens.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <42D7D802.2080100@fujitsu-siemens.com> Subject: [uml-devel] Re: Some changes in SKAS0 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: Fri, 12 Aug 2005 13:09:00 -0400 To: Bodo Stroesser Cc: user-mode-linux devel , BlaisorBlade >From our discussion yesterday, ... On Fri, Jul 15, 2005 at 05:36:34PM +0200, Bodo Stroesser wrote: > So I thought about avoiding the sigreturn at all. Working on > this I found out some small points: I kept this patch > - there is a bug (typo) in wait_stub_done() but dropped these two, plus my dont-save-fpregs patch. Correct? > - stopping stub_segv_handler with a "breakpoint" without > calling sigreturn, lets SIGSEGV being blocked after that. > At the next SIGSEGV, I see stub_wait_done() calling panic > just as with Rob's problem. And I see the child being gone! > I understand, that the host unblocks SIGSEGV and sets the > handler to SIG_DFL. But I don't understand, why the child > already is gone after the waitpid(), without resuming it. > I guess, this is the reason for Rob not being able to debug > the problem. > Thus I added SA_NOMASK to the flags for the handler. > > - I changed the additional mask for the handler to be empty. > The only exception is x86_64, that currently must use sigreturn > and therefore still masks SIGUSR1 while the handler runs. > In skas, userspace shouldn't receive SIGIO or SIGWINCH (I hope > I'm right here?), SIGVTALRM already is handled by wait_stub_done. > Then I changed i386's stub_segv_handler to stop using "int3" > immediately after saving faultinfo. > This new method saves some syscalls on i386 and s390 and > simplifies s390. Jeff ------------------------------------------------------- SF.Net email is Sponsored by the Better Software Conference & EXPO September 19-22, 2005 * San Francisco, CA * Development Lifecycle Practices Agile & Plan-Driven Development * Managing Projects & Teams * Testing & QA Security * Process Improvement & Measurement * http://www.sqe.com/bsce5sf _______________________________________________ User-mode-linux-devel mailing list User-mode-linux-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/user-mode-linux-devel