From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail.alien8.de (mail.alien8.de [65.109.113.108]) (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 B755F374187; Wed, 12 Aug 2026 20:05:15 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=65.109.113.108 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1786565118; cv=none; b=hrnYanXShcFPl/KmFhNgGpoVTv9RSLdVCoB1/loL9MJoIQJcZexz9X6deC6LAaT8ilXfoZD3bHORFYf1u+QRo+m/Q/xN0+HEsLkYFb7BdgDSJrygR8aqDqzAZQx99ttWDtXfaPxMg+ZNc/xndHWJNyMaKdpiBwg3e+qvVedNqns= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1786565118; c=relaxed/simple; bh=4vhTRc1/dX1D34Vcc2xvEiUy1eUBo/ZiHS7drQU0aoA=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=ZvKBSPsYwmbdwloHij4q0cdMYWvFqCRMKsIyA03RPH5D1OiIsiWuX8f87Snv7NBHlHnF4pElptTcWdzlOfND21L5GdGbVRkl6Zs53YuZ4RH5K0IlXHl48ZrNBA2ZqHTv5Q+dRtjzFbQnIme9+ZSFAW3ArFzN2lYlIxlJVXoWFnw= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=alien8.de; spf=pass smtp.mailfrom=alien8.de; dkim=pass (4096-bit key) header.d=alien8.de header.i=@alien8.de header.b=fk9bQ2GF; arc=none smtp.client-ip=65.109.113.108 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=alien8.de Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=alien8.de Authentication-Results: smtp.subspace.kernel.org; dkim=pass (4096-bit key) header.d=alien8.de header.i=@alien8.de header.b="fk9bQ2GF" Received: from localhost (localhost.localdomain [127.0.0.1]) by mail.alien8.de (SuperMail on ZX Spectrum 128k) with ESMTP id 7926B40E019E; Wed, 12 Aug 2026 20:05:13 +0000 (UTC) X-Virus-Scanned: Debian amavisd-new at mail.alien8.de Authentication-Results: mail.alien8.de (amavisd-new); dkim=pass (4096-bit key) header.d=alien8.de Received: from mail.alien8.de ([127.0.0.1]) by localhost (mail.alien8.de [127.0.0.1]) (amavisd-new, port 10026) with ESMTP id 9NTlaYtYKV85; Wed, 12 Aug 2026 20:05:03 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=alien8.de; s=alien8; t=1786565103; bh=6dBQkg+AiyaWmAjZedH4XYQHET6jIziOv8yV3K7UfrU=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=fk9bQ2GFg0WBzx1knvI7zfntSMNhLYqZLQEOY6NMnq4GdSpAhHnEjaoqhLr+XzkeL tSkRf8BTrFumNd5LJwzwyONszFhqBVt/yvTPQVT6jRSFgWfH/6jG3t2XGasNX/4uW/ bvG+ufYtZe8UK4YLGXxnGOYMws1Q/vqFBXP7fIoHCvHjkA1ohrKeFgZ98uOnSeE+cN djrO0d7cDTyLpWZ96j2wOg2crbfXpDasUrJ77KstV6OtvrJ1uJP891HMcIpHROiV7F G8dy1tLNskNHyE7xtkfb1YCcuOG/iUPZ3zheo8ICTsHrI+/TwpO4GGcR5QNz6TL1wW Qv9q9HP9tBgiQxk6ABjIzJXevfgrb0H11ItKIY8ltUgFvaUhfhrvrG+FyNKw9GlHea b0kjcMfw5az+bwmHa5OET2dxiZCXYJXW4MTDpB5dPem2RHyRoOrmCEja86Rsdz9w2w A3mUrD756oreZCqVd+nDTePWhAfZ7ZvEWSmRItUUmuqaQOmRkh24m6zvShmo860G12 T4V/V6ayvwjxj4l07TZCjl++DcJmQ6Hxqn2i22MYisa/53ICRAWmI5YxX2e617+ZSa GNPvh+SdOi0cEa/UExeMlQ3DpdebFQFfngOXaww3BdIcd70w/jFxrxh5Nibl8wGIPr EmSOCXEAD7Kk/j5eydk2G2kI= Received: from stx.tnic (unknown [IPv6:2600:1700:38ca:c00::1b]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange ECDHE (P-256) server-signature ECDSA (P-256) server-digest SHA256) (No client certificate requested) by mail.alien8.de (SuperMail on ZX Spectrum 128k) with ESMTPSA id D7F2F40E019C; Wed, 12 Aug 2026 20:04:54 +0000 (UTC) Date: Wed, 12 Aug 2026 13:04:51 -0700 From: Borislav Petkov To: Eric Biggers Cc: x86@kernel.org, linux-um@lists.infradead.org, linux-raid@vger.kernel.org, linux-crypto@vger.kernel.org, linux-kernel@vger.kernel.org, Christoph Hellwig , Andrew Morton Subject: Re: [PATCH v2 1/8] x86/fpu: Check for missing AVX and AVX-512 xstate bits Message-ID: <20260812200451.GCanzR41yxY2n_62fs@fat_crate.local> References: <20260728021603.79870-2-ebiggers@kernel.org> <20260728052727.GCamg9v5WxNieTMUwE@fat_crate.local> <20260728054532.GA99797@sol> <20260728182007.GBamjy17zynlWm2gQT@fat_crate.local> <20260728183447.GB3355536@google.com> <20260728225936.GBamk0WK38PByPFkxz@fat_crate.local> <20260728233430.GA3277@quark> <20260728234726.GCamk_jnl3LtfGbxoC@fat_crate.local> <20260812174826.GAanyx6vUWv5GLX2AZ@fat_crate.local> <20260812194011.GA3734410@google.com> Precedence: bulk X-Mailing-List: linux-crypto@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <20260812194011.GA3734410@google.com> On Wed, Aug 12, 2026 at 07:40:11PM +0000, Eric Biggers wrote: > Interesting, so the !boot_cpu_has(X86_FEATURE_FPU) check is dead code > since ab05214025ee ("x86/fpu: Remove MATH_EMULATION and related glue > code"). Sure, there's no need to add anything to there then, though we > should do a separate patch that removes it. Sure. > Sure, that works. I'm not sure it's actually easier to understand than > what I proposed; it's kind of contradictory to call > "setup_clear_cpu_cap(X86_FEATURE_XSAVE)" when we just verified it is > clear. But the comment mentioning that it's actually for clearing > dependent flags helps. If you prefer this way, let's do this. Yes please, that's why I added the comment. And we have this machinery in do_clear_cpu_cap() so let's use it. > It's functionally equivalent, but yes we can write it this way if you > prefer. Is it okay if I fold your diff (minus the pr_info()) into this > patch? (I'll also add FW_BUG to the error messages as Thomas > requested.) Yap, that's perfectly fine. Thanks. -- Regards/Gruss, Boris. https://people.kernel.org/tglx/notes-about-netiquette