From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail.mixaill.net (mail.mixaill.net [144.76.234.135]) (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 746CB5474C for ; Wed, 12 Mar 2025 13:36:18 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=144.76.234.135 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1741786580; cv=none; b=bTqJX6ms4keTeGjDFS+cvBptJCW0N/zbnCgym6pvGB1TjpeUKHJzrZSydz8rkS8GU+8WxMuux8CgHC1FaXHcN0zoL+D9rgbmKVsNaqfV3STvYPIcS48tedZjCI1++f4mA/yQP3cMUNP+efO7xrXQzJw2TEfbQUbunBnoegqvhG4= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1741786580; c=relaxed/simple; bh=cP9TOort8UDbRdFcMVU/1z8wOgpvIIaKCmiC9n52nto=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=FxwuTbRrj9GOycv+qDRACk4dEhda672wrwLdxVzYfhV+rg9SAGW+Aps93E2pbBgSaYe+T0NqLogQfw5YE13x/Xawoovbb+rYN1L9Zrel3HB6QZ2DfNTifXWlZRn+e4n3hd9ob4WjhkkIXbx3X7VbQHV3RGIpfYgsuQVEW2Vt8sI= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=mixaill.net; spf=pass smtp.mailfrom=mixaill.net; dkim=pass (2048-bit key) header.d=mixaill.net header.i=@mixaill.net header.b=Vx7qBigk; arc=none smtp.client-ip=144.76.234.135 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=mixaill.net Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=mixaill.net Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=mixaill.net header.i=@mixaill.net header.b="Vx7qBigk" Received: from [127.0.0.1] (localhost [127.0.0.1]) by localhost (Mailerdaemon) with ESMTPSA id A89D661BAD; Wed, 12 Mar 2025 13:36:14 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=mixaill.net; s=dkim; t=1741786576; h=from:subject:date:message-id:to:cc:mime-version:content-type: content-transfer-encoding:content-language:in-reply-to:references; bh=1kJWyf2G03T60ssCrbVlJjK2wYFQEcclWEmwastU/so=; b=Vx7qBigkIRMstljmFMtGAPjgc32inVOFbaOnDfTOAuLv/HVi7uoTwWA/hyYtaDjO9mHNQe 5xHIKOA+7+ujOPAkMmE2q0fSg8Fy6azEZpGjlZNOStr8gRZDn83bms0ze3FAM7X0gqK43E WhIOXeGN0b/LviVWekrvi2b7A+Px8eUm21n5JLbXYwP18ds5B59fQrEcr7hWp1xZCi+gsY ixP71y3WICBg0UMp5Gz5TjTsmmhJMXngLnMpnt/T15HDtta3XCTaEg6ni9ZI8HEhPLEiTw 3GZ7KST6UyAcaizREIr+J+qdNn1TWiWWMRGiAeOyRNG5xPFIjzZ5mG8pb2kv3g== Message-ID: <2916bccf-a252-4a57-bb4b-efb8703fd909@mixaill.net> Date: Wed, 12 Mar 2025 16:36:13 +0300 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH 2/2] x86/rdrand: hide RDRAND and RDSEED from CPUID in case of a malfunction To: Borislav Petkov Cc: Thomas Gleixner , Ingo Molnar , Dave Hansen , x86@kernel.org, linux-kernel@vger.kernel.org References: <20250312123130.8290-1-me@mixaill.net> <20250312123130.8290-3-me@mixaill.net> <20250312124530.GDZ9GB6vscPTpDv8Aq@fat_crate.local> Content-Language: en-US From: Mikhail Paulyshka In-Reply-To: <20250312124530.GDZ9GB6vscPTpDv8Aq@fat_crate.local> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-Last-TLS-Session-Version: TLSv1.3 On 3/12/25 3:45 PM, Borislav Petkov wrote: > On Wed, Mar 12, 2025 at 03:31:30PM +0300, Mikhail Paulyshka wrote: >> @@ -46,6 +47,8 @@ void x86_init_rdrand(struct cpuinfo_x86 *c) >> >> if (failure) { >> clear_cpu_cap(c, X86_FEATURE_RDRAND); >> + if (c->x86_vendor == X86_VENDOR_AMD || c->x86_vendor == X86_VENDOR_HYGON) > Hygon is family 0x18. Have you tested it there? My bad, I thought Hygon is backwards compatible with AMD Zen1/2. Then it can be removed in case Hygon's MSRs are different.