From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from sc8-sf-mx2-b.sourceforge.net ([10.3.1.12] helo=sc8-sf-mx2.sourceforge.net) by sc8-sf-list1.sourceforge.net with esmtp (Exim 4.30) id 1CSl3T-0004iL-1s for user-mode-linux-devel@lists.sourceforge.net; Fri, 12 Nov 2004 15:42:11 -0800 Received: from smtp002.mail.ukl.yahoo.com ([217.12.11.33]) by sc8-sf-mx2.sourceforge.net with smtp (Exim 4.41) id 1CSl3S-00029D-4E for user-mode-linux-devel@lists.sourceforge.net; Fri, 12 Nov 2004 15:42:10 -0800 From: Blaisorblade Subject: Re: [uml-devel] Patchset to implement PTRACE_SYSEMU_SINGLESTEP References: <419517A4.7020700@fujitsu-siemens.com> In-Reply-To: <419517A4.7020700@fujitsu-siemens.com> MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-15" Content-Transfer-Encoding: 7bit Content-Disposition: inline Message-Id: <200411130043.25888.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: Sat, 13 Nov 2004 00:43:25 +0100 To: user-mode-linux-devel@lists.sourceforge.net Cc: Bodo Stroesser , Jeff Dike On Friday 12 November 2004 21:05, Bodo Stroesser wrote: > Attached are several patches. Four of them (patch-2.6.*-skas-v7-*) > implement PTRACE_SYSEMU_SINGLESTEP in the host. They are based on > linux-2.6.7-vanilla + host-skas3-2.6.7-v7.patch (resp. the 2.6.9 versions). > The "-reorganize" patches are a rework of the current patch without > changing the functionality. The "add-SYSEMU_SINGLESTEP" then implement the > new features. Please note: the differences between 2.6.7 and 2.6.9 are > dependent on the different handling of syscall singlestepping in the two > versions. > > To have UML using the new feature, there are two further patches named > patch-SYSEMU_SINGLESTEP-*. They are based on linux-2.6.9-vanilla + > all bb2-patches + patch-sysemu-tt + patch-fix-uml-hang-on-2.6.9-host. > To have all the patches complete, the latter two are attached also. > > I tested on host 2.6.7 and host 2.6.9 with SKAS and TT mode. Currently I > don't know any problem with it. > Bodo > BTW: Today I tried the first time since weeks to do a reboot in SKAS. It > simply exits UML, as it did weeks ago. Is there anybody involved with that > problem? It seems a bit randomical: on my system, it segfaults some times, after checking for /proc/mm and SKAS mode. When applying my use-va_end patch, (it's also in Jeff incrementals), instead, it always gets this segfault. If you look at the comment about exec(), it says that UML risks to get some signals after the exec(). It workarounds this for some signals, but this cannot be done anyway for SIGSEGV... actually SIGSEGV delivery happens to always be synchronous, since the process gets trapped before the signal is queued. By comparison, all signals are normally asynchronous, i.e. they get queued and later delivered, so that deliverying a signal is slower than doing a context switch. Quoting from signal(7) man page: Multiple instances of real-time signals can be queued. By contrast, if multiple instances of a standard signal are delivered while that signal is currently blocked, then only one instance is queued. -- Paolo Giarrusso, aka Blaisorblade Linux registered user n. 292729 ------------------------------------------------------- This SF.Net email is sponsored by: InterSystems CACHE FREE OODBMS DOWNLOAD - A multidimensional database that combines robust object and relational technologies, making it a perfect match for Java, C++,COM, XML, ODBC and JDBC. www.intersystems.com/match8 _______________________________________________ User-mode-linux-devel mailing list User-mode-linux-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/user-mode-linux-devel