From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 514D0CD5BCB for ; Thu, 5 Sep 2024 15:06:04 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1smE2o-0001lA-Dz; Thu, 05 Sep 2024 11:05:10 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1smE2m-0001jr-9U for qemu-devel@nongnu.org; Thu, 05 Sep 2024 11:05:08 -0400 Received: from todd.t-8ch.de ([159.69.126.157]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1smE2k-0000fH-4V for qemu-devel@nongnu.org; Thu, 05 Sep 2024 11:05:08 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=t-8ch.de; s=mail; t=1725548701; bh=1RtpgcPhEEYYwXcKrUAWQ3EjVVph3Z2nVQEfKOTbS1A=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=U9ec/p2m2zWsVi6ZcrHFfHBJxd3khBMSOt54rVmMDNp9UJUo4AtTRCE0LXBVAbAwo dseUtqWYWnSxy8SJf/bjW6ef4CZN/uirDKs1xSMXBAFDS+O6xEULjkPt8VF6bkM2F8 r1voyy7IOUjXWxLLRqVBxTySbV5g4Flfi1pLA/1I= Date: Thu, 5 Sep 2024 17:05:00 +0200 From: Thomas =?utf-8?Q?Wei=C3=9Fschuh?= To: "Jason A. Donenfeld" Cc: maobibo , loongarch@lists.linux.dev, qemu-devel@nongnu.org, xry111@xry111.site Subject: Re: qemu direct kernel boot on LoongArch Message-ID: References: <1738d60a-df3a-4102-b1da-d16a29b6e06a@t-8ch.de> <49432aed-3ed7-2f07-7f65-311faef96197@loongson.cn> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: Received-SPF: pass client-ip=159.69.126.157; envelope-from=thomas@t-8ch.de; helo=todd.t-8ch.de X-Spam_score_int: -20 X-Spam_score: -2.1 X-Spam_bar: -- X-Spam_report: (-2.1 / 5.0 requ) BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, SPF_HELO_NONE=0.001, SPF_PASS=-0.001, T_SCC_BODY_TEXT_LINE=-0.01 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org On 2024-09-05 16:53:55+0000, Jason A. Donenfeld wrote: > On Thu, Sep 05, 2024 at 07:25:05AM +0200, Thomas Weißschuh wrote: > > On 2024-09-05 06:04:12+0000, Jason A. Donenfeld wrote: > > > On Thu, Sep 5, 2024 at 5:45 AM maobibo wrote: > > > > > > > > Jason, > > > > > > > > With the latest qemu 9.1 version, elf format booting is supported. > > > > > > Thanks, I just figured this out too, about 4 minutes ago. Excellent. > > > And the 1G minimum ram limit is gone too. > > > > > > Now working on how to trigger resets. > > > > With "reset" do you mean normal (non-panic) system shutdown/poweroff? > > Since QEMU 9.1 and a recent kernel you can use the pvpanic device for > > that in a cross-architecture way. > > What I mean is that I need for userspace calling `reboot(RB_AUTOBOOT);` > to actually result in QEMU being told to reboot the system. Sounds like > that's not possible (yet?) in 9.1? With reboot(RB_POWER_OFF) this is indeed the exact usecase for pvpanic shutdown support. Reboot is not supported, but maybe -action shutdown=reboot works and is enough. It would also be trivial to extend pvpanic for reboot support. Use -device pvpanic-pci for QEMU and CONFIG_PVPANIC_PCI=y for Linux. (That should work for most architectures)