From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from lindbergh.monkeyblade.net (lindbergh.monkeyblade.net [23.128.96.19]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 5DE2E27EDD for ; Tue, 24 Oct 2023 17:30:27 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b="a/fOm95V" Received: from mgamail.intel.com (mgamail.intel.com [192.55.52.88]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 1378FD7F; Tue, 24 Oct 2023 10:30:26 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1698168626; x=1729704626; h=date:from:to:cc:subject:message-id:references: mime-version:in-reply-to; bh=4eTWR985NBV3mAvJMXvgeRN/dPF8gIx1f+55k33TMFE=; b=a/fOm95V579m4pvk+0O/p+2Qyt1N+DUnZHLK/ZS5Ri+qB8tgOKqPXQX0 vBDPTtmR8OrAfP2UEvVpndmmkx1cAMZBWjhIpFdR8FeshrrVxUlAu71wJ 4GA2MfRXW6MhrLb0wMCKw2sIpkambUhneMuAnZ+waCvthPSF0esK33vMk rc9wLnSCh2/0eic1KeZ9rQ+sFTXF9djaQLJEcWjsBQolw+0s11z30L/ML xRV7G7RqDUcZ8+FvdJj1wZGNmQG3ojf5BZNxNfbjxgdVs/HlZxqgrVjaE XmJdUi65uGrSLHPG9td43+ooh9hoTG6Ugw/Y41VdU6dNvrPUEuNJj9OBd Q==; X-IronPort-AV: E=McAfee;i="6600,9927,10873"; a="418247965" X-IronPort-AV: E=Sophos;i="6.03,248,1694761200"; d="scan'208";a="418247965" Received: from orsmga002.jf.intel.com ([10.7.209.21]) by fmsmga101.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 24 Oct 2023 10:30:25 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6600,9927,10873"; a="758554073" X-IronPort-AV: E=Sophos;i="6.03,248,1694761200"; d="scan'208";a="758554073" Received: from zijianw1-mobl.amr.corp.intel.com (HELO desk) ([10.209.109.187]) by orsmga002-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 24 Oct 2023 10:30:24 -0700 Date: Tue, 24 Oct 2023 10:30:15 -0700 From: Pawan Gupta To: Peter Zijlstra 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: <20231024173015.w5qw767akvcdwmiv@desk> 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> <20231024170248.GE40044@noisy.programming.kicks-ass.net> Precedence: bulk X-Mailing-List: linux-doc@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20231024170248.GE40044@noisy.programming.kicks-ass.net> On Tue, Oct 24, 2023 at 07:02:48PM +0200, Peter Zijlstra wrote: > 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. Ah, okay. Thanks for the info.