From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by smtp.subspace.kernel.org (Postfix) with ESMTP id 8337834CF5; Mon, 30 Jun 2025 10:21:18 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=217.140.110.172 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1751278880; cv=none; b=osh/t4AZqzplHRQCI+jzPwI4zRG4R/TjCdMDF2WURK0/mYFRiBfWKvyWbRsgSrk7DdyX2/4S1YdxH+slOM7mMMWFXHTVDH7Kr56aEfC7acNJGrDjy6egvgyurtuXyhJ1VegcqE00idajoppFUBpqPeIP9HWZXd1noRDfv5PgoYk= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1751278880; c=relaxed/simple; bh=gd5ly1mJwxfTxHVXTiDXU1nAFy8ObA7vyFEsPg04wrk=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=hhIHytJNvSKlhr6Rqh5kGAmY0FrHNCuA5JTpZK3GVcGHOuP0uJX2HRwDTANcZsEdUo6ccjsIe/acPtY0rbozWCa3eascg6sdVGDnIVBu/nwWzVXZ9/2y21fLzDCDM2xd4pJRczwUlL/WCiCbDxbgU3TR7wOACQqzjdMaHsySaJA= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com; spf=pass smtp.mailfrom=arm.com; arc=none smtp.client-ip=217.140.110.172 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=arm.com Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 20C931D34; Mon, 30 Jun 2025 03:21:02 -0700 (PDT) Received: from [10.1.196.46] (e134344.arm.com [10.1.196.46]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id BD3323F58B; Mon, 30 Jun 2025 03:21:15 -0700 (PDT) Message-ID: Date: Mon, 30 Jun 2025 11:21:14 +0100 Precedence: bulk X-Mailing-List: linux-kselftest@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH 0/3] arm64: Support FEAT_LSFE (Large System Float Extension) To: Mark Brown , Catalin Marinas , Will Deacon , Jonathan Corbet , Marc Zyngier , Oliver Upton , Joey Gouly , Suzuki K Poulose , Shuah Khan Cc: linux-arm-kernel@lists.infradead.org, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, kvmarm@lists.linux.dev, linux-kselftest@vger.kernel.org References: <20250627-arm64-lsfe-v1-0-68351c4bf741@kernel.org> Content-Language: en-US From: Ben Horgan In-Reply-To: <20250627-arm64-lsfe-v1-0-68351c4bf741@kernel.org> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Hi Mark, On 6/27/25 18:20, Mark Brown wrote: > FEAT_LSFE is optional from v9.5, it adds new instructions for atomic > memory operations with floating point values. We have no immediate use > for it in kernel, provide a hwcap so userspace can discover it and allow > the ID register field to be exposed to KVM guests. > > Signed-off-by: Mark Brown > --- > Mark Brown (3): > arm64/hwcap: Add hwcap for FEAT_LSFE > KVM: arm64: Expose FEAT_LSFE to guests > kselftest/arm64: Add lsfe to the hwcaps test > > Documentation/arch/arm64/elf_hwcaps.rst | 4 ++++ > arch/arm64/include/asm/hwcap.h | 1 + > arch/arm64/include/uapi/asm/hwcap.h | 1 + > arch/arm64/kernel/cpufeature.c | 2 ++ > arch/arm64/kernel/cpuinfo.c | 1 + > arch/arm64/kvm/sys_regs.c | 4 +++- > tools/testing/selftests/arm64/abi/hwcap.c | 21 +++++++++++++++++++++ > 7 files changed, 33 insertions(+), 1 deletion(-) I have looked through the series and it looks good to me modulo a couple of minor comments left on the patches. Bare in mind fairly new here and this is the first use of hwcap3 so I expect more experienced review is required. Reviewed-by: Ben Horgan > --- > base-commit: 86731a2a651e58953fc949573895f2fa6d456841 > change-id: 20250625-arm64-lsfe-0810cf98adc2 > > Best regards, > -- > Mark Brown > > Thanks, Ben