Re: [PATCH 4.9 02/31] Bluetooth: hci_ldisc: Postpone HCI_UART_PROTO_READY bit set in hci_uart_set_proto()

From: Greg Kroah-Hartman
Date: Mon Nov 18 2019 - 23:47:08 EST


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