Re: [PATCH 1/1] Drivers: hv: vmbus: Fix ring buffer signaling

[Stephen Hemminger]

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.