From: Michael Brown <mcb30@ipxe.org>
Date: Fri, 17 Oct 2025 11:34:03 +0000 (+0100)
Subject: [ena] Add memory barrier after writing to on-device memory
X-Git-Tag: rolling/bin~122
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=0ae5e25de2f8490c7be85a441ae7d7537d9b7445;p=thirdparty%2Fipxe.git

[ena] Add memory barrier after writing to on-device memory

Ensure that writes to on-device memory have taken place before writing
to the doorbell register.

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

diff --git a/src/drivers/net/ena.c b/src/drivers/net/ena.c
index b90a57c07..5dd0ef23e 100644
--- a/src/drivers/net/ena.c
+++ b/src/drivers/net/ena.c
@@ -1125,6 +1125,7 @@ static int ena_transmit ( struct net_device *netdev, struct io_buffer *iobuf ) {
 		dest = ( ena->tx.sq.llqe + ( index * sizeof ( *llqe ) ) );
 		for ( i = 0 ; i < ( sizeof ( *llqe ) / sizeof ( *src ) ); i++ )
 			writeq ( *(src++), dest++ );
+		wmb();
 	}
 
 	/* Increment producer counter */