Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67;
Date:   Tue, 19 Nov 2019 05:47:03 +0100
From:   Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To:     Ralph Siemsen <ralph.siemsen@linaro.org>
Cc:     linux-kernel@vger.kernel.org, stable@vger.kernel.org,
        syzbot+899a33dc0fa0dbaf06a6@syzkaller.appspotmail.com,
        Kefeng Wang <wangkefeng.wang@huawei.com>,
        Jeremy Cline <jcline@redhat.com>,
        Marcel Holtmann <marcel@holtmann.org>
Subject: Re: [PATCH 4.9 02/31] Bluetooth: hci_ldisc: Postpone
 HCI_UART_PROTO_READY bit set in hci_uart_set_proto()
Message-ID: <20191119044703.GA1451491@kroah.com>
References: <20191115062009.813108457@linuxfoundation.org>
 <20191115062010.682028342@linuxfoundation.org>
 <20191115161029.GA32365@maple.netwinder.org>
 <20191116075614.GB381281@kroah.com>
 <20191118202712.GA14832@maple.netwinder.org>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <20191118202712.GA14832@maple.netwinder.org>
User-Agent: Mutt/1.12.2 (2019-09-21)
Sender: linux-kernel-owner@vger.kernel.org
Precedence: bulk

On Mon, Nov 18, 2019 at 03:27:12PM -0500, Ralph Siemsen wrote:
> On Sat, Nov 16, 2019 at 03:56:14PM +0800, Greg Kroah-Hartman wrote:
> > > 
> > > BTW, this also seems to be missing from 4.4 branch, although it was merged
> > > for 3.16 (per https://lore.kernel.org/stable/?q=Postpone+HCI).
> > 
> > Odd that it was merged into 3.16, perhaps it was done there because some
> > earlier patch added the problem?
> 
> This patch should really be viewed as a correction to an earlier commit:
> 84cb3df02aea ("Bluetooth: hci_ldisc: Fix null pointer derefence in case of
> early data"). This was merged 2016-Apr-08 into v4.7, and therefore is
> included in 4.9 and higher.
> 
> Only very recently, on 2019-Sep-23, this was backported to 3.16, along with
> the correction. Both appeared in v3.16.74.

Ok, that makes more sense now.  The "fix" didn't apply as it was not a
fix for an old issue, but rather a new one.

> > I say this as I do not think this is
> > relevant for the 4.4.y kernel, do you?  Have you tried to apply this
> > patch there?
> 
> The patch does not apply, but this is mainly due to the earlier commit
> missing. It seems to me like that earlier fix is desirable (and it was put
> into 3.16), along with the followup. So I would think we want it in 4.4 as
> well.

I've queued them both up now, thanks.

> [Aside: I'm really only interested in 4.9 and 4.19, so the 4.4 stuff is just
> a diversion. But figured I might as well mention what I found...]

Other people at your company care about 4.4.y :)

thanks,

greg k-h