Re: [PATCH hyperv-fixes] hv_netvsc: fix race that may miss tx queue wakeup

From: David Miller
Date: Fri May 03 2019 - 23:51:46 EST


From: Haiyang Zhang <haiyangz@xxxxxxxxxxxxx>
Date: Tue, 30 Apr 2019 19:29:07 +0000

> When the ring buffer is almost full due to RX completion messages, a
> TX packet may reach the "low watermark" and cause the queue stopped.
> If the TX completion arrives earlier than queue stopping, the wakeup
> may be missed.
>
> This patch moves the check for the last pending packet to cover both
> EAGAIN and success cases, so the queue will be reliably waked up when
> necessary.
>
> Reported-and-tested-by: Stephan Klein <stephan.klein@xxxxxxxxxxxx>
> Signed-off-by: Haiyang Zhang <haiyangz@xxxxxxxxxxxxx>

Applied, thanks.