From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from out-176.mta1.migadu.com (out-176.mta1.migadu.com [95.215.58.176]) (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 B22364D8C3 for ; Thu, 18 Jul 2024 06:09:17 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=95.215.58.176 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1721282961; cv=none; b=bNved5T92b87i1z+jyOK8+di5uvcv/peNzHHEiEyjzQucKd5PXeZAaGiVixhDAhAfKcpHt8EOE1im3MRlJvCQ7GH8KRQ9v9Y7K3mvjO/9szohLT1EeGi5DSKgacT6DoPA3GTd92ra55QDiXocnQOUNgvAG9PInEEFYgqs+0VcGU= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1721282961; c=relaxed/simple; bh=8TELw1GSGX+NLZTXJBpEVR3AisUwDBU+WRnsu8/phTc=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=aOgm1UU1YUFKujcGMaGqKRP9v6V18KAQdcgeZB9IcN0VDESxgAZyc+VqOEwO1pza53fj5Mbiv0Tb8Ip7sc0rqNy/42qf7uO2HYFWVeeYApr5qc4zJjw51Q0ZYup29bq3oARnXpkEhZaw3P3IMrBxKYi0PocCLQLoW5Et469IsEI= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev; spf=pass smtp.mailfrom=linux.dev; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b=e1SBxS09; arc=none smtp.client-ip=95.215.58.176 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.dev Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b="e1SBxS09" X-Envelope-To: shahuang@redhat.com DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1721282955; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=wUojTRMLIjKYQq/hlr2+G8wV6gdnpgRx4UJFibcBjBU=; b=e1SBxS09mQ3CMf4e+UZpBoSQDSzMz1BJzitVzq98YCRnQS3ndTKz7jp+cC68IJ+RNx6VUQ TaAbG1IGb/gycpsjVZrl2K+oYxRLylCdnHuDyeXPA2z7WvmvaUJOwv1GdeoxqR7jH9YAUq 6YCpUdssAdsYsyMPD2OrAzqavsge2zI= X-Envelope-To: maz@kernel.org X-Envelope-To: kvmarm@lists.linux.dev X-Envelope-To: broonie@kernel.org X-Envelope-To: eauger@redhat.com X-Envelope-To: sebott@redhat.com X-Envelope-To: cohuck@redhat.com X-Envelope-To: james.morse@arm.com X-Envelope-To: suzuki.poulose@arm.com X-Envelope-To: yuzenghui@huawei.com X-Envelope-To: catalin.marinas@arm.com X-Envelope-To: will@kernel.org X-Envelope-To: linux-arm-kernel@lists.infradead.org X-Envelope-To: linux-kernel@vger.kernel.org Date: Wed, 17 Jul 2024 23:09:08 -0700 X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. From: Oliver Upton To: Shaoqin Huang Cc: Marc Zyngier , kvmarm@lists.linux.dev, Mark Brown , Eric Auger , Sebastian Ott , Cornelia Huck , James Morse , Suzuki K Poulose , Zenghui Yu , Catalin Marinas , Will Deacon , linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v4 1/3] KVM: arm64: Disable fields that KVM doesn't know how to handle in ID_AA64PFR1_EL1 Message-ID: References: <20240718035017.434996-1-shahuang@redhat.com> <20240718035017.434996-2-shahuang@redhat.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20240718035017.434996-2-shahuang@redhat.com> X-Migadu-Flow: FLOW_OUT Hi Shaoqin, On Wed, Jul 17, 2024 at 11:50:14PM -0400, Shaoqin Huang wrote: > For some of the fields in the ID_AA64PFR1_EL1 register, KVM doesn't know > how to handle them right now. So explicitly disable them in the register > accessor, then those fields value will be masked to 0 even if on the > hardware the field value is 1. It is probably important to note that the only reason this is safe to do from a UAPI POV is that read_sanitised_ftr_reg() doesn't yet return a nonzero value for any of these fields. -- Thanks, Oliver