From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail.ptr1337.dev (mail.ptr1337.dev [202.61.224.105]) (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 9D6DC313E09; Mon, 3 Nov 2025 13:59:21 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=202.61.224.105 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1762178363; cv=none; b=bOR/htdYPQm0Vr+2Y7tLn8W1BMTx6zal/GTvhgR1oVEHo5yEx0OgnMOiKWJKvt2G/Kd/8mH5K2WK1sA2/t5ZDWMC35PTigc7Ow9t2ukM86l+LIpPM2OvnQoC3pl5jB7Dioh2331Q8VH8KPpPjRIzpd2hi4RPNdlC9RmtnHh4SdQ= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1762178363; c=relaxed/simple; bh=M01mIC/VTNf5sx9PsqT/xkduCCmmcdT+VQitzYUK5xg=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=JX9+tlC8YUfBBfik1AH1XruNhBLHKO9qJF1TwrPxFqsDuV2FUt6BIe/xe6QS+tnSzCd3g6YEDEO451QQzMfgrJJKeZ/dpfjbYdYnIJYaCKE1MzP1myi16iyc6a80tBFFMzhnZfqc/GXvc3eqkFMwwSovDWG2YuxappxKwfRSOWY= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=cachyos.org; spf=pass smtp.mailfrom=cachyos.org; dkim=pass (2048-bit key) header.d=cachyos.org header.i=@cachyos.org header.b=GEfKXPQr; arc=none smtp.client-ip=202.61.224.105 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=cachyos.org Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=cachyos.org Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=cachyos.org header.i=@cachyos.org header.b="GEfKXPQr" Received: from [127.0.0.1] (localhost [127.0.0.1]) by localhost (Mailerdaemon) with ESMTPSA id D2123284517; Mon, 3 Nov 2025 14:59:12 +0100 (CET) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=cachyos.org; s=dkim; t=1762178353; h=from:subject:date:message-id:to:cc:mime-version:content-type: content-transfer-encoding:content-language:in-reply-to:references; bh=gle31eN9My17sC8D8ST/fOHC6I96gUMv9nuTZ5ksc/Y=; b=GEfKXPQrOj68YuHKsvQcSn2lxGj3ONIs3yYNF5MlmbOGWzoJ3D4QYjP6f/C+0MhW5z6X82 Rqal6B/YZZJuSRnTppTvOCie2Ei6IjsLy3RXQi1vqR/gaPyrci/NdvL0CfwAdgB/OG3FfB h6qN+eTpfBUsXI6UtxjGJhr2ysTXquLOqM0BEemlmUjoP+WsJrHMgHxQpTV8Qx0jg9yE1C tCUoQcaHezjHRTWWl7JyTivYesSCfhQrs7j0ogEYArt8mD1lEe6UD2tV6DN8w0s4l5RPfS CsIXqtLiXWtEUziWPs+LF/2dwQJMCC4KGjc2v3AvSkveqvR+IXlwZSr6hvOjQg== Message-ID: <9a27f2e6-4f62-45a6-a527-c09983b8dce4@cachyos.org> Date: Mon, 3 Nov 2025 14:59:11 +0100 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: [tip: x86/urgent] x86/CPU/AMD: Add RDSEED fix for Zen5 To: linux-kernel@vger.kernel.org, linux-tip-commits@vger.kernel.org Cc: stable@vger.kernel.org, Gregory Price , "Borislav Petkov (AMD)" , x86@kernel.org References: <176165291198.2601451.3074910014537130674.tip-bot2@tip-bot2> Content-Language: en-US From: Peter Jung Organization: CachyOS In-Reply-To: <176165291198.2601451.3074910014537130674.tip-bot2@tip-bot2> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-Last-TLS-Session-Version: TLSv1.3 On 10/28/25 13:01, tip-bot2 for Gregory Price wrote: > The following commit has been merged into the x86/urgent branch of tip: > > Commit-ID: 607b9fb2ce248cc5b633c5949e0153838992c152 > Gitweb:https://git.kernel.org/tip/607b9fb2ce248cc5b633c5949e0153838992c152 > Author: Gregory Price > AuthorDate: Mon, 20 Oct 2025 11:13:55 +02:00 > Committer: Borislav Petkov (AMD) > CommitterDate: Tue, 28 Oct 2025 12:37:49 +01:00 > > x86/CPU/AMD: Add RDSEED fix for Zen5 > > There's an issue with RDSEED's 16-bit and 32-bit register output > variants on Zen5 which return a random value of 0 "at a rate inconsistent > with randomness while incorrectly signaling success (CF=1)". Search the > web for AMD-SB-7055 for more detail. > > Add a fix glue which checks microcode revisions. > > [ bp: Add microcode revisions checking, rewrite. ] > > Cc:stable@vger.kernel.org > Signed-off-by: Gregory Price > Signed-off-by: Borislav Petkov (AMD) > Link:https://lore.kernel.org/r/20251018024010.4112396-1-gourry@gourry.net > --- > arch/x86/kernel/cpu/amd.c | 10 ++++++++++ > 1 file changed, 10 insertions(+) > > diff --git a/arch/x86/kernel/cpu/amd.c b/arch/x86/kernel/cpu/amd.c > index ccaa51c..bc29be6 100644 > --- a/arch/x86/kernel/cpu/amd.c > +++ b/arch/x86/kernel/cpu/amd.c > @@ -1035,8 +1035,18 @@ static void init_amd_zen4(struct cpuinfo_x86 *c) > } > } > > +static const struct x86_cpu_id zen5_rdseed_microcode[] = { > + ZEN_MODEL_STEP_UCODE(0x1a, 0x02, 0x1, 0x0b00215a), > + ZEN_MODEL_STEP_UCODE(0x1a, 0x11, 0x0, 0x0b101054), > +}; > + > static void init_amd_zen5(struct cpuinfo_x86 *c) > { > + if (!x86_match_min_microcode_rev(zen5_rdseed_microcode)) { > + clear_cpu_cap(c, X86_FEATURE_RDSEED); > + msr_clear_bit(MSR_AMD64_CPUID_FN_7, 18); > + pr_emerg_once("RDSEED32 is broken. Disabling the corresponding CPUID bit.\n"); > + } > } > > static void init_amd(struct cpuinfo_x86 *c) > Hi all, This fix seems to break quite a bunch of users in CachyOS. There has been now several users reporting that there system can not get properly into the graphical interface. CachyOS is compiling the packages with -march=znver5 and the GCC compiler currently does pass RDSEED. This patch results into that also Client CPUs (Strix Point, Granite Ridge), can not execute this. There has been a microcode fix deployed in linux-firmware for Turin, but no other microcode changes seen yet. I think it would be possible to exclude clients or providing a fix for this. Example log: Nov 03 13:37:33 hells drkonqi-coredump-processor[1073]: Incompatible processor. This Qt build requires the following features: Nov 03 13:37:33 hells drkonqi-coredump-processor[1073]: rdseed Nov 03 13:37:33 hells systemd-coredump[1077]: Process 1073 (drkonqi-coredum) of user 0 terminated abnormally with signal 6/ABRT, processing... Nov 03 13:37:33 hells systemd[1]: Started Process Core Dump (PID 1077/UID 0). Nov 03 13:37:33 hells systemd[1]: Started Pass systemd-coredump journal entries to relevant user for potential DrKonqi handling. Nov 03 13:37:33 hells drkonqi-coredump-processor[1079]: Incompatible processor. This Qt build requires the following features: Nov 03 13:37:33 hells drkonqi-coredump-processor[1079]: rdseed Nov 03 13:37:33 hells systemd-coredump[1082]: Process 1079 (drkonqi-coredum) of user 0 terminated abnormally with signal 6/ABRT, processing... Nov 03 13:37:33 hells systemd-coredump[1071]: Process 1049 (sddm) of user 0 dumped core. Best regards, Peter