svn commit: r296024 - head/sys/dev/hyperv/netvsc

[Sepherosa Ziehau]

Author: sephe
Date: Thu Feb 25 07:03:10 2016
New Revision: 296024
URL: https://svnweb.freebsd.org/changeset/base/296024

Log:
  hyperv/hn: Hold the TX ring lock then drain TX desc buf_ring
  
  Reported by:	Hongxiong Xian <v-hoxian microsoft com>
  MFC after:	1 week
  Sponsored by:	Microsoft OSTC

Modified:
  head/sys/dev/hyperv/netvsc/hv_netvsc_drv_freebsd.c

Modified: head/sys/dev/hyperv/netvsc/hv_netvsc_drv_freebsd.c
==============================================================================
--- head/sys/dev/hyperv/netvsc/hv_netvsc_drv_freebsd.c	Thu Feb 25 04:32:17 2016	(r296023)
+++ head/sys/dev/hyperv/netvsc/hv_netvsc_drv_freebsd.c	Thu Feb 25 07:03:10 2016	(r296024)
@@ -2326,8 +2326,10 @@ hn_destroy_tx_ring(struct hn_tx_ring *tx
 		hn_txdesc_dmamap_destroy(txd);
 	}
 #else
+	mtx_lock(&txr->hn_tx_lock);
 	while ((txd = buf_ring_dequeue_sc(txr->hn_txdesc_br)) != NULL)
 		hn_txdesc_dmamap_destroy(txd);
+	mtx_unlock(&txr->hn_tx_lock);
 #endif
 
 	if (txr->hn_tx_data_dtag != NULL)