Re: [PATCH 1/1] Drivers: hv: vmbus: Fix ring buffer signaling
From: Greg KH
Date: Thu Mar 29 2018 - 03:25:22 EST
On Wed, Mar 28, 2018 at 12:01:42PM -0700, Stephen Hemminger wrote:
> On Sun, 4 Mar 2018 22:24:08 -0700
> kys@xxxxxxxxxxxxxxxxxxxxxx wrote:
>
> > From: Michael Kelley <mhkelley@xxxxxxxxxxx>
> >
> > 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@xxxxxxxxxxxxxxx> # 4.14 and above
> > Signed-off-by: Michael Kelley <mhkelley@xxxxxxxxxxx>
> > Signed-off-by: K. Y. Srinivasan <kys@xxxxxxxxxxxxx>
>
> What ever happened to this patch? It doesn't seem to be in char-misc, upstream,
> or stable kernel tree yet.
>
It was in the 4.14.31 and 4.15.14 stable releases.
thanks,
greg k-h