From: "Stephen Hemminger" <stephen@networkplumber.org>
To: "'Joshua R. Poulson'" <jrp@pun.org>
Cc: "'K. Y. Srinivasan'" <kys@exchange.microsoft.com>,
        "'KY Srinivasan'" <kys@microsoft.com>,
        <gregkh@linuxfoundation.org>, <linux-kernel@vger.kernel.org>,
        <devel@linuxdriverproject.org>, <olaf@aepfle.de>,
        "'Andy Whitcroft'" <apw@canonical.com>,
        "'Vitaly Kuznetsov'" <vkuznets@redhat.com>, <jasowang@redhat.com>,
        "'Leann Ogasawara'" <leann.ogasawara@canonical.com>,
        "'Marcelo Henrique Cerri'" <marcelo.cerri@canonical.com>,
        "'Stephen Hemminger'" <sthemmin@microsoft.com>,
        "'Michael Kelley'" <mhkelley@outlook.com>,
        "'Stable'" <stable@vger.kernel.org>
References: <20180305052408.19475-1-kys@exchange.microsoft.com> <20180328120142.7ba72aa2@xeon-e3> <CABHrTi+pMjYX4jqaaXS=X02o7CbWBqdMMwcyrxo=BywV18n7WQ@mail.gmail.com>
In-Reply-To: <CABHrTi+pMjYX4jqaaXS=X02o7CbWBqdMMwcyrxo=BywV18n7WQ@mail.gmail.com>
Subject: RE: [PATCH 1/1] Drivers: hv: vmbus: Fix ring buffer signaling
Date: Wed, 28 Mar 2018 16:25:11 -0700
Message-ID: <03e101d3c6ec$05828e20$1087aa60$@networkplumber.org>
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Sender: stable-owner@vger.kernel.org

Thanks, I hadn't updated to rc7 yet


-----Original Message-----
From: Joshua R. Poulson <jrp@pun.org>=20
Sent: Wednesday, March 28, 2018 12:18 PM
To: Stephen Hemminger <stephen@networkplumber.org>
Cc: K. Y. Srinivasan <kys@exchange.microsoft.com>; KY Srinivasan =
<kys@microsoft.com>; gregkh@linuxfoundation.org; =
linux-kernel@vger.kernel.org; devel@linuxdriverproject.org; =
olaf@aepfle.de; Andy Whitcroft <apw@canonical.com>; Vitaly Kuznetsov =
<vkuznets@redhat.com>; jasowang@redhat.com; Leann Ogasawara =
<leann.ogasawara@canonical.com>; Marcelo Henrique Cerri =
<marcelo.cerri@canonical.com>; Stephen Hemminger =
<sthemmin@microsoft.com>; Michael Kelley <mhkelley@outlook.com>; Stable =
<stable@vger.kernel.org>
Subject: Re: [PATCH 1/1] Drivers: hv: vmbus: Fix ring buffer signaling

https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit=
/?h=3Dv4.16-rc7&id=3D655296c8bbeffcf020558c4455305d597a73bde1

On Wed, Mar 28, 2018 at 12:01 PM, Stephen Hemminger
<stephen@networkplumber.org> wrote:
> On Sun,  4 Mar 2018 22:24:08 -0700
> kys@exchange.microsoft.com wrote:
>
>> From: Michael Kelley <mhkelley@outlook.com>
>>
>> Fix bugs in signaling the Hyper-V host when freeing space in the
>> host->guest ring buffer:
>>
>> 1. The interrupt_mask must not be used to determine whether to signal
>>    on the host->guest ring buffer
>> 2. The ring buffer write_index must be read (via =
hv_get_bytes_to_write)
>>    *after* pending_send_sz is read in order to avoid a race condition
>> 3. Comparisons with pending_send_sz must treat the "equals" case as
>>    not-enough-space
>> 4. Don't signal if the pending_send_sz feature is not present. Older
>>    versions of Hyper-V that don't implement this feature will poll.
>>
>> Fixes: 03bad714a161 ("vmbus: more host signalling avoidance")
>>
>> Cc: Stable <stable@vger.kernel.org> # 4.14 and above
>> Signed-off-by: Michael Kelley <mhkelley@outlook.com>
>> Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
>
> What ever happened to this patch? It doesn't seem to be in char-misc, =
upstream,
> or stable kernel tree yet.
>
>