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 mm01.cs.columbia.edu (mm01.cs.columbia.edu [128.59.11.253]) by smtp.lore.kernel.org (Postfix) with ESMTP id EC23EC433EF for ; Mon, 22 Nov 2021 17:58:11 +0000 (UTC) Received: from localhost (localhost [127.0.0.1]) by mm01.cs.columbia.edu (Postfix) with ESMTP id 3B3C34B172; Mon, 22 Nov 2021 12:58:11 -0500 (EST) X-Virus-Scanned: at lists.cs.columbia.edu Authentication-Results: mm01.cs.columbia.edu (amavisd-new); dkim=softfail (fail, message has been altered) header.i=@kernel.org Received: from mm01.cs.columbia.edu ([127.0.0.1]) by localhost (mm01.cs.columbia.edu [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id 2DQ7f5loT2h1; Mon, 22 Nov 2021 12:58:10 -0500 (EST) Received: from mm01.cs.columbia.edu (localhost [127.0.0.1]) by mm01.cs.columbia.edu (Postfix) with ESMTP id 260AF4B0E6; Mon, 22 Nov 2021 12:58:10 -0500 (EST) Received: from localhost (localhost [127.0.0.1]) by mm01.cs.columbia.edu (Postfix) with ESMTP id 4CB424B0E1 for ; Mon, 22 Nov 2021 12:58:08 -0500 (EST) X-Virus-Scanned: at lists.cs.columbia.edu Received: from mm01.cs.columbia.edu ([127.0.0.1]) by localhost (mm01.cs.columbia.edu [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id CtdYV0YvSU6L for ; Mon, 22 Nov 2021 12:58:07 -0500 (EST) Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by mm01.cs.columbia.edu (Postfix) with ESMTPS id 2013A4B0C5 for ; Mon, 22 Nov 2021 12:58:07 -0500 (EST) Received: by mail.kernel.org (Postfix) with ESMTPSA id B97BC60C4A; Mon, 22 Nov 2021 17:58:03 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1637603885; bh=xaPvWRRZLplWuTj6zfL8WONxOMLolZjyxQW/VUcabzM=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=TaGnGGcyBXQBLJ9W61wVeyz/MNc33lttcCzOEXoIzohiqYDXGAVQhE/bdAdCQXoBo Ji9T5Zp7wrEbdDIlf9DGI/ID7+/9eAuP+S/XvPWVFA06C0C1GR8bWQErfGKxKAKPs7 BaIHVWzvDJo+7Lr4fSQAcdza1HzrY7X46t4hqxjL0W2a0jSq8m/ROoxl6lW7P2Y1To O8bUzzD65jVr0byC6hNreFKUVASfB3oUMhvcfA0i6vnpZECT08FV5sKjJBK0n+axbr lCSWQlBgmjz62gQHH5T6bmkD11Y4a0ZKB0GMMhq9rJs63xQaDPaOz4QvipZTMPSCIQ wHO6s9Sz4CcBg== Date: Mon, 22 Nov 2021 17:58:00 +0000 From: Mark Brown To: Marc Zyngier Subject: Re: [PATCH v2 2/5] KVM: arm64: Get rid of host SVE tracking/saving Message-ID: References: <20211028111640.3663631-1-maz@kernel.org> <20211028111640.3663631-3-maz@kernel.org> <5ab3836f-2b39-2ff5-3286-8258addd01e4@huawei.com> <871r38dvyr.wl-maz@kernel.org> MIME-Version: 1.0 In-Reply-To: <871r38dvyr.wl-maz@kernel.org> X-Cookie: Lake Erie died for your sins. Cc: kernel-team@android.com, kvm@vger.kernel.org, Will Deacon , kvmarm@lists.cs.columbia.edu, linux-arm-kernel@lists.infradead.org X-BeenThere: kvmarm@lists.cs.columbia.edu X-Mailman-Version: 2.1.14 Precedence: list List-Id: Where KVM/ARM decisions are made List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: multipart/mixed; boundary="===============1312281066326142411==" Errors-To: kvmarm-bounces@lists.cs.columbia.edu Sender: kvmarm-bounces@lists.cs.columbia.edu --===============1312281066326142411== Content-Type: multipart/signed; micalg=pgp-sha512; protocol="application/pgp-signature"; boundary="4ejJzEuy+GX8OnS7" Content-Disposition: inline --4ejJzEuy+GX8OnS7 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline On Mon, Nov 22, 2021 at 03:57:32PM +0000, Marc Zyngier wrote: > Zenghui Yu wrote: > > Nit: This removes the only user of __sve_save_state() helper. Should we > > still keep it in fpsimd.S? > I was in two minds about that, as I'd like to eventually be able to > use SVE for protected guests, where the hypervisor itself has to be in > charge of the FP/SVE save-restore. > But that's probably several months away, and I can always revert a > deletion patch if I need to, so let's get rid of it now. While we're on the subject of potential future work we might in future want to not disable SVE on every syscall if (as seems likely) it turns out that that's more performant for small vector lengths which would mean some minor reshuffling here to do something like convert the saved state to FPSIMD and drop TIF_SVE in _vcpu_load_fp(). As with using SVE in protected guests that can just be done when needed though. --4ejJzEuy+GX8OnS7 Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iQEzBAABCgAdFiEEreZoqmdXGLWf4p/qJNaLcl1Uh9AFAmGb2icACgkQJNaLcl1U h9BczQf+IBminM9LlYcrYBFvkLv1xG/VjhSrXo0RiCzpz5QehpsZDC2Xycu4+seo 7y5r3IXniQ0R4FAA68e9D2FT/ubuwBJ72cZ/eBdW5QWMFoX0dZMk3v+/YiDVxch0 hr/ZUAVDB6qsgjVXoUeuYJxfBuxlDnDUbB4zMw+PjP9mMcgg9aTzO4kgQ8VHd9q0 OkCT/fyP1zl0yaKtcFXeg2fsJWvJgOp+SnwQ+z5ht1jnCkb2t+iXO48wpg0YETtd Uw5m/QMMsg/7Sy2WBjCB/gY2ThljfBpLY9CgbESPFNbyamfxDF/NWJZs6Bs/qHOB y0I6Gy6DMi9nbVMYHcuZgcq+XzWlOg== =9M+3 -----END PGP SIGNATURE----- --4ejJzEuy+GX8OnS7-- --===============1312281066326142411== Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Disposition: inline _______________________________________________ kvmarm mailing list kvmarm@lists.cs.columbia.edu https://lists.cs.columbia.edu/mailman/listinfo/kvmarm --===============1312281066326142411==--