From: Michael Brown <mcb30@ipxe.org>
Date: Mon, 6 Oct 2025 15:39:19 +0000 (+0100)
Subject: [gve] Add missing memory barriers
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=c2d7ddd0c2855a935e0ba7987a300bcecc46261a;p=thirdparty%2Fipxe.git

[gve] Add missing memory barriers

Ensure that remainder of completion records are read only after
verifying the generation bit (or sequence number).

Signed-off-by: Michael Brown <mcb30@ipxe.org>
---

diff --git a/src/drivers/net/gve.c b/src/drivers/net/gve.c
index 11ef35351..1696c249d 100644
--- a/src/drivers/net/gve.c
+++ b/src/drivers/net/gve.c
@@ -1493,6 +1493,7 @@ static void gve_poll_tx ( struct net_device *netdev ) {
 			bit = ( dqo->flags & GVE_DQO_TXF_GEN );
 			if ( ( !! bit ) == ( !! gen ) )
 				break;
+			rmb();
 			tx->done++;
 
 			/* Ignore non-packet completions */
@@ -1583,6 +1584,7 @@ static void gve_poll_rx ( struct net_device *netdev ) {
 			bit = ( dqo->len & cpu_to_le16 ( GVE_DQO_RXL_GEN ) );
 			if ( ( !! bit ) == ( !! gen ) )
 				break;
+			rmb();
 
 			/* Parse completion */
 			len = ( le16_to_cpu ( dqo->len ) &
@@ -1610,6 +1612,7 @@ static void gve_poll_rx ( struct net_device *netdev ) {
 			/* Check sequence number */
 			if ( ( gqi->seq & GVE_GQI_RX_SEQ_MASK ) != seq )
 				break;
+			rmb();
 			seq = gve_next ( seq );
 
 			/* Parse completion */