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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (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 55090C52D7B for ; Tue, 13 Aug 2024 15:55:46 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:Content-Type: List-Subscribe:List-Help:List-Post:List-Archive:List-Unsubscribe:List-Id: In-Reply-To:MIME-Version:References:Message-ID:Subject:Cc:To:From:Date: Reply-To:Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date :Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=USaQ/e3VV2wa3VHdiA7FwngECeH0TKQivW4stXRBPpk=; b=Tw8Hp7507qgF1T9kr53ecuqyH6 ZSYkK0Ks20g8Mh1frIOcRJEikh6evzkiZI058Qju81vjX7GvcBRCyrEy2RWq9JW1agNtUMjq6sHpi +FqLgdEErRD4ECLSds1oRbJY2iLh7eSl2crF571JPLxXU7n2deo/bTH2uZc5fw+AbxYTUEurIARI1 tXUBhk+VeJRemFp0N9hMJZp3n4D0GNYcbKEyxQkPQi0jMxSxWy5LSUFLXRNydSTegyvOKFxTfbvlX pZa1WhB2YU+2tLF3mbztQfHYwWAxRL/Ks39/TFNql0qsi/+XVcBQymPdODnFwT3FNtyqPg44De4df A7Z+ZUIg==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.97.1 #2 (Red Hat Linux)) id 1sdts2-00000004Gy9-0wpt; Tue, 13 Aug 2024 15:55:38 +0000 Received: from dfw.source.kernel.org ([2604:1380:4641:c500::1]) by bombadil.infradead.org with esmtps (Exim 4.97.1 #2 (Red Hat Linux)) id 1sdtrz-00000004GwE-24mm for linux-riscv@lists.infradead.org; Tue, 13 Aug 2024 15:55:37 +0000 Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by dfw.source.kernel.org (Postfix) with ESMTP id BEF576174C; Tue, 13 Aug 2024 15:55:34 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 3B120C4AF09; Tue, 13 Aug 2024 15:55:29 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1723564534; bh=2qbznLVAWa/HOCkibpwEKuFx9BRG0jfLiyGPm/O5D0U=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=TdDaa/og08j0LYWxMjIfmT62Kse6nlmDNAqFUWXRmeAOd4L8HUcdtoNGpFIKZ2ovK Wo8eroMPA7ljNcvycCtAJoCPSOW0sL4ez8CU0njPbAl5s4w3e1pL1xt0z/5bkAsd3W AyI8VSs3BZHOYosptDMzpeCBZYGxHn2H8y8LbYAnhcsMLr91GM20TL0ixceE9tPfzb Vx1zlFj6nEUair4k8rdOYdoG4DTk8CIJwZHafLxB8o8P/RrW8+9bZFSBxfXNpqDFNr VwMB5tfnO4Fx23eAhjULiqlqOWHy4r2C5DEKNZSBu0vrreLkayROtBxCfuvWvflTI4 xxXxYgEv0gapw== Date: Tue, 13 Aug 2024 16:55:27 +0100 From: Conor Dooley To: Charlie Jenkins Cc: Rob Herring , Krzysztof Kozlowski , Paul Walmsley , Palmer Dabbelt , Albert Ou , Jisheng Zhang , Chen-Yu Tsai , Jernej Skrabec , Samuel Holland , Samuel Holland , Jonathan Corbet , Shuah Khan , Guo Ren , Evan Green , Andy Chiu , Jessica Clarke , Andrew Jones , linux-riscv@lists.infradead.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, linux-sunxi@lists.linux.dev, linux-doc@vger.kernel.org, linux-kselftest@vger.kernel.org, Conor Dooley , Heiko Stuebner Subject: Re: [PATCH v9 00/13] riscv: Add support for xtheadvector Message-ID: <20240813-strode-revival-07b8556a8bfe@spud> References: <20240806-xtheadvector-v9-0-62a56d2da5d0@rivosinc.com> <20240809-slapping-graph-461287bac506@spud> MIME-Version: 1.0 In-Reply-To: X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20240813_085535_644669_8D55E83A X-CRM114-Status: GOOD ( 23.91 ) X-BeenThere: linux-riscv@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: multipart/mixed; boundary="===============1832788651176568277==" Sender: "linux-riscv" Errors-To: linux-riscv-bounces+linux-riscv=archiver.kernel.org@lists.infradead.org --===============1832788651176568277== Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="wVALGEdsN5/GZu0E" Content-Disposition: inline --wVALGEdsN5/GZu0E Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Mon, Aug 12, 2024 at 05:45:30PM -0700, Charlie Jenkins wrote: > On Fri, Aug 09, 2024 at 11:31:15PM +0100, Conor Dooley wrote: > > On Tue, Aug 06, 2024 at 05:31:36PM -0700, Charlie Jenkins wrote: > > > xtheadvector is a custom extension that is based upon riscv vector > > > version 0.7.1 [1]. All of the vector routines have been modified to > > > support this alternative vector version based upon whether xtheadvect= or > > > was determined to be supported at boot. > > >=20 > > > vlenb is not supported on the existing xtheadvector hardware, so a > > > devicetree property thead,vlenb is added to provide the vlenb to Linu= x. > > >=20 > > > There is a new hwprobe key RISCV_HWPROBE_KEY_VENDOR_EXT_THEAD_0 that = is > > > used to request which thead vendor extensions are supported on the > > > current platform. This allows future vendors to allocate hwprobe keys > > > for their vendor. > > >=20 > > > Support for xtheadvector is also added to the vector kselftests. > >=20 > > So uh, since noone seems to have brought it up, in the light of the iss= ues > > with thead's vector implementation, (https://ghostwriteattack.com/) do = we > > want to enable it at all? >=20 > I can make it clear in the kconfig that xtheadvector is succeptible to > this attack and that it should be enabled with caution. I think we > should let people that understand the risk to enable it. I think the clearest way might be "depends on BROKEN"? --wVALGEdsN5/GZu0E Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iHUEABYIAB0WIQRh246EGq/8RLhDjO14tDGHoIJi0gUCZruB7wAKCRB4tDGHoIJi 0tDJAQCrAAwyJAAGcGaB0lSjHQowc1+M+60A33xWLVpFubDEggD+PdA/5VviAMYd FtjIx2BGIAbBB5DLVfsxw4duVA3eAQc= =/cR1 -----END PGP SIGNATURE----- --wVALGEdsN5/GZu0E-- --===============1832788651176568277== Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Disposition: inline _______________________________________________ linux-riscv mailing list linux-riscv@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-riscv --===============1832788651176568277==--