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 40A9AC4345F for ; Tue, 23 Apr 2024 15:17:30 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1rzHng-0007S3-FZ; Tue, 23 Apr 2024 11:11:16 -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 1rzHn8-0004eB-TK for qemu-devel@nongnu.org; Tue, 23 Apr 2024 11:10:46 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1rzHn5-0000H2-SG for qemu-devel@nongnu.org; Tue, 23 Apr 2024 11:10:42 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1713885035; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=K3b4NZw12C67fnamLmqGsicV6QSJgJKW9M7T4Bs+Krw=; b=K0UFeoqNRb2oYTp9vlZOuMV26/di4cK+Q3z4xfA93eXOokGtZkhcTr21M7lthfhN7YGQUo 0vkyAk97ldIwWVSmKkSpG6uhD+l4MlsoyGXlo8hdyQRFkqYzF+cmh+rW7Um22XDi1pgFOa 64urgne0Xyb0c4BYu4jB/cIir+nbvlM= Received: from mimecast-mx02.redhat.com (mx-ext.redhat.com [66.187.233.73]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-570-vEZD-7t_Mtu7tNDSbX1CVA-1; Tue, 23 Apr 2024 11:10:33 -0400 X-MC-Unique: vEZD-7t_Mtu7tNDSbX1CVA-1 Received: from smtp.corp.redhat.com (int-mx04.intmail.prod.int.rdu2.redhat.com [10.11.54.4]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 4272F29AC015; Tue, 23 Apr 2024 15:10:33 +0000 (UTC) Received: from avogadro.lan (unknown [10.39.192.70]) by smtp.corp.redhat.com (Postfix) with ESMTP id 9DBC8200E290; Tue, 23 Apr 2024 15:10:32 +0000 (UTC) From: Paolo Bonzini To: qemu-devel@nongnu.org Cc: =?UTF-8?q?Philippe=20Mathieu-Daud=C3=A9?= Subject: [PULL 39/63] runstate: skip initial CPU reset if reset is not actually possible Date: Tue, 23 Apr 2024 17:09:27 +0200 Message-ID: <20240423150951.41600-40-pbonzini@redhat.com> In-Reply-To: <20240423150951.41600-1-pbonzini@redhat.com> References: <20240423150951.41600-1-pbonzini@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-Scanned-By: MIMEDefang 3.4.1 on 10.11.54.4 Received-SPF: pass client-ip=170.10.133.124; envelope-from=pbonzini@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -27 X-Spam_score: -2.8 X-Spam_bar: -- X-Spam_report: (-2.8 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.67, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, RCVD_IN_MSPIKE_H4=0.001, RCVD_IN_MSPIKE_WL=0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 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 Right now, the system reset is concluded by a call to cpu_synchronize_all_post_reset() in order to sync any changes that the machine reset callback applied to the CPU state. However, for VMs with encrypted state such as SEV-ES guests (currently the only case of guests with non-resettable CPUs) this cannot be done, because guest state has already been finalized by machine-init-done notifiers. cpu_synchronize_all_post_reset() does nothing on these guests, and actually we would like to make it fail if called once guest has been encrypted. So, assume that boards that support non-resettable CPUs do not touch CPU state and that all such setup is done before, at the time of cpu_synchronize_all_post_init(). Reviewed-by: Philippe Mathieu-Daudé Signed-off-by: Paolo Bonzini --- system/runstate.c | 15 ++++++++++++++- 1 file changed, 14 insertions(+), 1 deletion(-) diff --git a/system/runstate.c b/system/runstate.c index d6ab860ecaa..cb4905a40fc 100644 --- a/system/runstate.c +++ b/system/runstate.c @@ -501,7 +501,20 @@ void qemu_system_reset(ShutdownCause reason) default: qapi_event_send_reset(shutdown_caused_by_guest(reason), reason); } - cpu_synchronize_all_post_reset(); + + /* + * Some boards use the machine reset callback to point CPUs to the firmware + * entry point. Assume that this is not the case for boards that support + * non-resettable CPUs (currently used only for confidential guests), in + * which case cpu_synchronize_all_post_init() is enough because + * it does _more_ than cpu_synchronize_all_post_reset(). + */ + if (cpus_are_resettable()) { + cpu_synchronize_all_post_reset(); + } else { + assert(runstate_check(RUN_STATE_PRELAUNCH)); + } + vm_set_suspended(false); } -- 2.44.0