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[2620:137:e000::3:5]) by mx.google.com with ESMTPS id bq6-20020a056a02044600b005aa7d3730dcsi9174988pgb.82.2023.10.24.10.03.30 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 24 Oct 2023 10:03:48 -0700 (PDT) Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::3:5 as permitted sender) client-ip=2620:137:e000::3:5; Authentication-Results: mx.google.com; dkim=pass header.i=@infradead.org header.s=desiato.20200630 header.b=lcZZU9f+; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::3:5 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: from out1.vger.email (depot.vger.email [IPv6:2620:137:e000::3:0]) by groat.vger.email (Postfix) with ESMTP id 9533780A8B93; Tue, 24 Oct 2023 10:03:28 -0700 (PDT) X-Virus-Status: Clean X-Virus-Scanned: clamav-milter 0.103.10 at groat.vger.email Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1343980AbjJXRDX (ORCPT + 99 others); Tue, 24 Oct 2023 13:03:23 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:48488 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232329AbjJXRDW (ORCPT ); Tue, 24 Oct 2023 13:03:22 -0400 Received: from desiato.infradead.org (desiato.infradead.org [IPv6:2001:8b0:10b:1:d65d:64ff:fe57:4e05]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 22DCD123; Tue, 24 Oct 2023 10:03:20 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=desiato.20200630; h=In-Reply-To:Content-Type:MIME-Version: References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description; bh=a8IeFdJ8fia0YpbA1ZcZvRmzA2TI5SE/1rrfo0EUgMw=; b=lcZZU9f+QLz2bVRJlnc/UxbjTE nMk0Ob5/6FcqIEwN0NPgITv3XKH/BkS47qVAJYnx8r3lhYpiDcxdS215jd9kuls2QSrsI1kslzSOB AUDZBvNIq8pu1syL0aXeyR/jcQYFauWKel20Qpjc4NBAErE6EFvPiTcplnLUwYvD3N/kEYrDIrrAZ 73w6BQIh8IJLNn+c52e0IisU8xHm/kOo53LlbrKwj2m5QJvQ/LOmxrXFc91IcBMP3/5Prki0v4A55 mnwHk9l8KjlmFYmlMWwPtsyIj5NyDz0JPghY/tylB+6DpMF7Sc87UMuH56nTJsx6A61Q1dy6IR40w mYFbWLfQ==; Received: from j130084.upc-j.chello.nl ([24.132.130.84] helo=noisy.programming.kicks-ass.net) by desiato.infradead.org with esmtpsa (Exim 4.96 #2 (Red Hat Linux)) id 1qvKno-00FfSi-2Y; Tue, 24 Oct 2023 17:02:48 +0000 Received: by noisy.programming.kicks-ass.net (Postfix, from userid 1000) id 7175B300451; Tue, 24 Oct 2023 19:02:48 +0200 (CEST) Date: Tue, 24 Oct 2023 19:02:48 +0200 From: Peter Zijlstra To: Pawan Gupta Cc: Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , x86@kernel.org, "H. Peter Anvin" , Josh Poimboeuf , Andy Lutomirski , Jonathan Corbet , Sean Christopherson , Paolo Bonzini , tony.luck@intel.com, ak@linux.intel.com, tim.c.chen@linux.intel.com, linux-kernel@vger.kernel.org, linux-doc@vger.kernel.org, kvm@vger.kernel.org, Alyssa Milburn , Daniel Sneddon , antonio.gomez.iglesias@linux.intel.com, Alyssa Milburn Subject: Re: [PATCH v2 1/6] x86/bugs: Add asm helpers for executing VERW Message-ID: <20231024170248.GE40044@noisy.programming.kicks-ass.net> References: <20231024-delay-verw-v2-0-f1881340c807@linux.intel.com> <20231024-delay-verw-v2-1-f1881340c807@linux.intel.com> <20231024103601.GH31411@noisy.programming.kicks-ass.net> <20231024163515.aivo2xfmwmbmlm7z@desk> <20231024163621.GD40044@noisy.programming.kicks-ass.net> <20231024164520.osvqo2dja2xhb7kn@desk> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20231024164520.osvqo2dja2xhb7kn@desk> X-Spam-Status: No, score=-0.8 required=5.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS autolearn=unavailable autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on groat.vger.email Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org X-Greylist: Sender passed SPF test, not delayed by milter-greylist-4.6.4 (groat.vger.email [0.0.0.0]); Tue, 24 Oct 2023 10:03:28 -0700 (PDT) On Tue, Oct 24, 2023 at 09:45:20AM -0700, Pawan Gupta wrote: > > > modules being within 4GB of kernel. FWIW, it's 2G, it's a s32 displacement, the highest most address can jump 2g down, while the lowest most address can jump 2g up. Leaving a 2G directly addressable range. And yeah, we ensure kernel text and modules are inside that 2G range.