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 3C5C7349CF3; Fri, 9 Oct 2026 04:38:50 +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=1791520731; cv=none; b=OMvltF9ZrsRWLOhL5r2T8Jbfb7UDHBWkneuB4knPcZf+W0aTTFI2uybVPn3P8H5/D4QGVIWKUjZWbNFycia/BIua3hwNLMOCFhjvNxL2+q43R+iYGZ8jhVtzXkHQ19E0/45yWIt4mQ+goG2cy1ZUM4w7wHJjFE3+zAYCmuWAD58= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1791520731; c=relaxed/simple; bh=1eHApctttwmY6Rtyg/wIpkMvoeSAqn+lvGZsSQ2WMkI=; h=Message-ID:Date:MIME-Version:Subject:To:References:From: In-Reply-To:Content-Type; b=g7fty2V1O6QAbV8i2Wkqg7A3dASvFiekE1aefIobF9NHY56LXHvH5GCNBlg1eQ9Ib+wNve8nUsU63fOfI+2M5CsGfLT/uyvgQIdl5vCLggJVaz8SZ4b+aBdE6KWulu297ulyNUe26jkqbCu1Pg/b+1hIM0q0y24ibnH2Kl1/KfM= 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=SHPJy9Sb; 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="SHPJy9Sb" Received: from [10.95.65.84] (unknown [52.172.102.253]) by linux.microsoft.com (Postfix) with ESMTPSA id 2D0F320B7166; Thu, 8 Oct 2026 21:38:45 -0700 (PDT) DKIM-Filter: OpenDKIM Filter v2.11.0 linux.microsoft.com 2D0F320B7166 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.microsoft.com; s=default; t=1791520729; bh=8H6c0N4ZGkWDbwW6f71HIiPk+xQG6yOk/RNBcbZj0BE=; h=Date:Subject:To:References:From:In-Reply-To:From; b=SHPJy9SbZT7BlTlVVIOk9EUByxzLSpZ2swriD7t14Hs6Bx7lDc6WNmljQWOZSY+Hk hniLpdKmbV1bbdBBDLQ9GSQ9kyqDM1Icjc9V68FZv7UjpBtg743AaaRqkN6QEg/oIs 3rzl6nkMBqo4tPcLeQ6fYN+YXeyxzi2ZXVXN+5zs= Message-ID: Date: Fri, 9 Oct 2026 10:08:43 +0530 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 1/1] Documentation: hyperv: Update documentation for sending VMBus packets To: mhklinux@outlook.com, haiyangz@microsoft.com, wei.liu@kernel.org, decui@microsoft.com, corbet@lwn.net, skhan@linuxfoundation.org, rdunlap@infradead.org, linux-kernel@vger.kernel.org, linux-hyperv@vger.kernel.org, linux-doc@vger.kernel.org References: <20261009030637.3869-1-mhklinux@outlook.com> Content-Language: en-US From: Naman Jain In-Reply-To: <20261009030637.3869-1-mhklinux@outlook.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit On 10/9/2026 8:36 AM, Michael Kelley wrote: > The functions for sending VMBus packets have been simplified. > vmbus_sendpacket_mpb_desc() can target multiple ranges, and > vmbus_sendpacket_pagebuffer() has been removed. Update the > documentation accordingly. > > Fixes: 45a442fe369e ("Drivers: hv: vmbus: Remove vmbus_sendpacket_pagebuffer()") > Cc: stable@vger.kernel.org > Signed-off-by: Michael Kelley > --- > The Fixes: tag reflects the code change that was made. The > documentation update should have been included with the > original code change. > > Documentation/virt/hyperv/vmbus.rst | 13 ++++--------- > 1 file changed, 4 insertions(+), 9 deletions(-) > > diff --git a/Documentation/virt/hyperv/vmbus.rst b/Documentation/virt/hyperv/vmbus.rst > index 654bb4849972..77a437969b49 100644 > --- a/Documentation/virt/hyperv/vmbus.rst > +++ b/Documentation/virt/hyperv/vmbus.rst > @@ -137,18 +137,13 @@ control message contains a list of GPAs that describe the data > buffer. For example, the storvsc driver uses this approach to > specify the data buffers to/from which disk I/O is done. > > -Three functions exist to send VMBus channel messages: > +Two functions exist to send VMBus channel messages: > > 1. vmbus_sendpacket(): Control-only messages and messages with > embedded data -- no GPAs > -2. vmbus_sendpacket_pagebuffer(): Message with list of GPAs > - identifying data to transfer. An offset and length is > - associated with each GPA so that multiple discontinuous areas > - of guest memory can be targeted. > -3. vmbus_sendpacket_mpb_desc(): Message with list of GPAs > - identifying data to transfer. A single offset and length is > - associated with a list of GPAs. The GPAs must describe a > - single logical area of guest memory to be targeted. > +2. vmbus_sendpacket_mpb_desc(): Message with one or more data ranges > + to target. Each range consists of a single offset and length plus > + a list of GPAs that describe a logical area of guest memory. > > Historically, Linux guests have trusted Hyper-V to send well-formed > and valid messages, and Linux drivers for synthetic devices did not vmbus_sendpacket_getid() is also part of the exported VMBus API and has an active caller in pci-hyperv.c. It might be useful to include it here and explain that it uses the same packet format as vmbus_sendpacket(), but additionally returns the transaction ID assigned to the packet. Otherwise, the update LGTM. Reviewed-by: Naman Jain Thanks, Naman Jain