From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mailman by lists.gnu.org with tmda-scanned (Exim 4.43) id 1KAoTM-0005ag-CZ for qemu-devel@nongnu.org; Mon, 23 Jun 2008 12:00:52 -0400 Received: from exim by lists.gnu.org with spam-scanned (Exim 4.43) id 1KAoTL-0005a2-BU for qemu-devel@nongnu.org; Mon, 23 Jun 2008 12:00:51 -0400 Received: from [199.232.76.173] (port=47759 helo=monty-python.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1KAoTJ-0005Ze-Lg for qemu-devel@nongnu.org; Mon, 23 Jun 2008 12:00:49 -0400 Received: from mail2.shareable.org ([80.68.89.115]:44329) by monty-python.gnu.org with esmtps (TLS-1.0:RSA_AES_256_CBC_SHA1:32) (Exim 4.60) (envelope-from ) id 1KAoTJ-0001U0-F1 for qemu-devel@nongnu.org; Mon, 23 Jun 2008 12:00:49 -0400 Date: Mon, 23 Jun 2008 17:00:47 +0100 From: Jamie Lokier Subject: Re: [Qemu-devel] Re: [RESENT][PATCH 2/2] x86: Issue reset on triple faults Message-ID: <20080623160047.GB16803@shareable.org> References: <485FBE18.4090603@siemens.com> <20080623152348.GA16375@shareable.org> <485FC2BC.3040503@siemens.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <485FC2BC.3040503@siemens.com> Reply-To: qemu-devel@nongnu.org List-Id: qemu-devel.nongnu.org List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Cc: kwolf@suse.de Jan Kiszka wrote: > > It might be worth distinguishing between > > triple-fault-used-by-guest-for-context-switch and triple faults which > > trigger a normal reset, and log only the latter. There's a > > standardish way of distinguishing them, which the BIOS should check. > > You refer to setting some return address at some magic BIOS location? Probably; I forget the details. There might be a CMOS byte, too. > Isn't this something the BIOS should handle, not QEMU? The BIOS should handle it, yes. But since it is standard behaviour, it might be useful for QEMU to decide whether to _log_ the event as a system reset based on that state. Same for keyboard controller induced reset - that's also used for context switching, in the same way. (Triple fault is only used because it's faster.) Same also for deciding whether -no-reboot should close down the QEMU process. Now I think about it, that is the best reason to distinguish them! > > When helper(SVM_EXIT_SHUTDOWN, 0) is called, should it still also call > > qemu_system_reset_request()? > > helper_vmexit() is not expected to return (cpu_loop_exit). Ok. It's not clear unless you know the code, which I don't. Just wanted to check :-) -- Jamie