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 X-Spam-Level: X-Spam-Status: No, score=-5.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 22B13C432BE for ; Thu, 2 Sep 2021 12:29:58 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id F01EE61059 for ; Thu, 2 Sep 2021 12:29:57 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1344333AbhIBMaz (ORCPT ); Thu, 2 Sep 2021 08:30:55 -0400 Received: from smtp-out1.suse.de ([195.135.220.28]:54322 "EHLO smtp-out1.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234094AbhIBMav (ORCPT ); Thu, 2 Sep 2021 08:30:51 -0400 Received: from imap1.suse-dmz.suse.de (imap1.suse-dmz.suse.de [192.168.254.73]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (P-521) server-digest SHA512) (No client certificate requested) by smtp-out1.suse.de (Postfix) with ESMTPS id A69C6225EB; Thu, 2 Sep 2021 12:29:52 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.de; s=susede2_rsa; t=1630585792; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=YTqZMysm+LJ+94OQTFSZh1X2ymjjfpUxWo7nIjwarjM=; b=RJ+TjjZVQTKKJk2Z36M9Of44tCfRPAvLCY8WN62mV+oV/HL/8Y9aGvwEfxLORFJ4PsfXZx pO5j6tiUGmRJAe5u3cCyEUWPW9vSaZa4lsleglN2SFH4WUfUT06LZntiINHTCgZ6Q9eBdW w3A/VxM6Ci5ntkOVOMAW0OwAn22Mubk= DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=suse.de; s=susede2_ed25519; t=1630585792; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=YTqZMysm+LJ+94OQTFSZh1X2ymjjfpUxWo7nIjwarjM=; b=kGN+vMCGABu5b5mMf+lNqdkdxSqr+QSEHMxdxEzVPP+/tQ3nQs2BThBnulrQDI7pfVuLbq +J2oXMuuRO+ewRBA== Received: from imap1.suse-dmz.suse.de (imap1.suse-dmz.suse.de [192.168.254.73]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (P-521) server-digest SHA512) (No client certificate requested) by imap1.suse-dmz.suse.de (Postfix) with ESMTPS id 34060132AB; Thu, 2 Sep 2021 12:29:52 +0000 (UTC) Received: from dovecot-director2.suse.de ([192.168.254.65]) by imap1.suse-dmz.suse.de with ESMTPSA id WRyvCsDDMGECBgAAGKfGzw (envelope-from ); Thu, 02 Sep 2021 12:29:52 +0000 Date: Thu, 2 Sep 2021 14:29:50 +0200 From: Joerg Roedel To: Lai Jiangshan Cc: Peter Zijlstra , Lai Jiangshan , linux-kernel@vger.kernel.org, Andy Lutomirski , Thomas Gleixner , Ingo Molnar , Borislav Petkov , x86@kernel.org, "H. Peter Anvin" , Youquan Song , Tony Luck Subject: Re: [PATCH 22/24] x86/entry: Implement and use do_paranoid_entry() and paranoid_exit() Message-ID: References: <20210831175025.27570-1-jiangshanlai@gmail.com> <20210831175025.27570-23-jiangshanlai@gmail.com> <44e08066-bbfb-222e-dffc-63e5b64f125f@linux.alibaba.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <44e08066-bbfb-222e-dffc-63e5b64f125f@linux.alibaba.com> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Sep 02, 2021 at 07:58:51PM +0800, Lai Jiangshan wrote: > Oh, #VC will need to switch stack. I think we need ASM code to switch > stack since the original stack need to be "free" for next #VC. Right, #VC switches off its IST stack to make it free for subsequent #VCs. The switch mostly happens in C code already, see vc_switch_off_ist(), only the actual RSP update is still ASM. Regards, Joerg