From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from linux.microsoft.com (linux.microsoft.com [13.77.154.182]) by smtp.subspace.kernel.org (Postfix) with ESMTP id D480B253B5C; Fri, 21 Feb 2025 20:01:37 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=13.77.154.182 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1740168099; cv=none; b=IQE2650/+w+F0U56nuvrz6TtUjFBxWA8dDwmJvm6Y0ddgOzy8uu+uvYTNCI+dRqxObgy0gFPaxJnKA3JhEVwfJXrtQnYijpYht/QJ/Z0ldn+llQ7eUmBSpfw+A1GR2303CbP2pV/bbx4qUQgWo+CLdjUlKOmhkircwwqV69bjWg= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1740168099; c=relaxed/simple; bh=3XgieEOBUGAAZvE8C5VsBMWxSTo4PYdIE8rWpuaj1s4=; h=Message-ID:Date:MIME-Version:Subject:From:To:Cc:References: In-Reply-To:Content-Type; b=aI55rRl7SbxP8mLaup1DEyx0RDxZMUNBTNxPUkOHvTn+BwcLAm37L3Hchiuln7esPcMzC3ruosIu5kJsJs8uHQbVe8Ip0zIlIW49Y1Rr5Z+ISfIn5A99Tv4lIZOQ3cjpxn15iS+d/Cjl8Ff7dSauIsSEpXEWo+uT2dRcOwRWvYs= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.microsoft.com; spf=pass smtp.mailfrom=linux.microsoft.com; dkim=pass (1024-bit key) header.d=linux.microsoft.com header.i=@linux.microsoft.com header.b=dygnEZ7c; arc=none smtp.client-ip=13.77.154.182 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.microsoft.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.microsoft.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux.microsoft.com header.i=@linux.microsoft.com header.b="dygnEZ7c" Received: from [10.0.0.114] (c-67-182-156-199.hsd1.wa.comcast.net [67.182.156.199]) by linux.microsoft.com (Postfix) with ESMTPSA id E7EC62069417; Fri, 21 Feb 2025 12:01:36 -0800 (PST) DKIM-Filter: OpenDKIM Filter v2.11.0 linux.microsoft.com E7EC62069417 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.microsoft.com; s=default; t=1740168097; bh=44dStVmRn1/6hW7hYJxHZ4v+2e/QWDNOYlE859iLC28=; h=Date:Subject:From:To:Cc:References:In-Reply-To:From; b=dygnEZ7czHywqTChRPKx3oed3NemHmKjVSvPaxfSp1FXfXKwdo9FSARhhWOhgaCk5 CUcGU7heUGdXEtTn+6eSprExcB579ljnj7s6nJQ/DFRjmSIts9zupM6yrzmxoL7BD5 2SGf5+3OX54Ub8APiiTDbg/y8tIlNB62mQfFPaJs= Message-ID: <991e7df9-d814-48a9-9469-a0b2f72acabb@linux.microsoft.com> Date: Fri, 21 Feb 2025 12:01:36 -0800 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 v2 0/3] Introduce CONFIG_MSHV_ROOT for root partition code From: Nuno Das Neves To: linux-hyperv@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, linux-arch@vger.kernel.org, iommu@lists.linux.dev, mhklinux@outlook.com, eahariha@linux.microsoft.com, mukeshrathor@microsoft.com Cc: kys@microsoft.com, haiyangz@microsoft.com, wei.liu@kernel.org, decui@microsoft.com, catalin.marinas@arm.com, will@kernel.org, tglx@linutronix.de, mingo@redhat.com, bp@alien8.de, dave.hansen@linux.intel.com, x86@kernel.org, hpa@zytor.com, daniel.lezcano@linaro.org, joro@8bytes.org, robin.murphy@arm.com, arnd@arndb.de, jinankjain@linux.microsoft.com, muminulrussell@gmail.com, skinsburskii@linux.microsoft.com References: <1740167795-13296-1-git-send-email-nunodasneves@linux.microsoft.com> Content-Language: en-US In-Reply-To: <1740167795-13296-1-git-send-email-nunodasneves@linux.microsoft.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit The subject line says v2 but this is actually v3! Nuno On 2/21/2025 11:56 AM, Nuno Das Neves wrote: > Running in the root partition is a unique and specialized case that > requires additional code. CONFIG_MSHV_ROOT allows Hyper-V guest kernels > to exclude this code, which is important since significant additional code > specific to the root partition is expected to be added over time. > > To do this, change hv_root_partition to be a function which is stubbed out > to return false if CONFIG_MSHV_ROOT=n, and don't compile hv_proc.c at all, > stubbing out those functions with inline versions. > > Store the partition type (guest or root) in an enum hv_curr_partition_type, > which can be extended beyond just guest and root partition. > > While at it, introduce hv_result_to_errno() to convert Hyper-V status codes > to regular linux errors. This is useful because the caller of a hypercall > helper function (such as those in hv_proc.c) usually can't and doesn't > interpret the Hyper-V status, so it is better to convert it to an error code > and reduce the possibility of misinterpreting it. This also alows the stubbed > versions of the hv_proc.c functions to just return a linux error code. > > Signed-off-by: Nuno Das Neves > --- > Changes in v3: > * Fix a typo [Easwar Hariharan] > * Fix ret being initialized to HV_STATUS_SUCCESS in some hypercall helpers > [Michael Kelley] > * Fix CONFIG_MSHV_ROOT being used in patch 2, before it is defined [Michael > Kelley] > * Shorten hv_current_partition_type to hv_curr_partition_type [Mukesh Rathor] > > Changes in v2: > * Add patch to convert hypercall statuses to linux error codes [Easwar > Hariharan] > * While at it, split the original patch into two logical pieces, one to change > hv_root_partition into a function, and one to introduce MSHV_CONFIG_ROOT > * Improve the clarity of and add an error message to > hv_identify_partition_type() [Easwar Hariharan] [Michael Kelley] > * Better explain *why* the patches are useful, in the commit messages [Michael > Kelley] > * Add a Kconfig comment explaining why PAGE_SIZE_4KB is needed [Michael Kelley] > * Minor style and typo fixes > > Nuno Das Neves (3): > hyperv: Convert hypercall statuses to linux error codes > hyperv: Change hv_root_partition into a function > hyperv: Add CONFIG_MSHV_ROOT to gate root partition support > > arch/arm64/hyperv/mshyperv.c | 2 + > arch/x86/hyperv/hv_init.c | 10 ++--- > arch/x86/kernel/cpu/mshyperv.c | 24 +---------- > drivers/clocksource/hyperv_timer.c | 4 +- > drivers/hv/Kconfig | 16 +++++++ > drivers/hv/Makefile | 3 +- > drivers/hv/hv.c | 10 ++--- > drivers/hv/hv_common.c | 69 +++++++++++++++++++++++++++--- > drivers/hv/hv_proc.c | 10 ++--- > drivers/hv/vmbus_drv.c | 2 +- > drivers/iommu/hyperv-iommu.c | 4 +- > include/asm-generic/mshyperv.h | 40 ++++++++++++++--- > 12 files changed, 139 insertions(+), 55 deletions(-) >