Module Name: src
Committed By: riastradh
Date: Sat Aug 20 11:31:39 UTC 2022
Modified Files:
src/sys/dev/ic: nvme.c
Log Message:
nvme(4): Read cqe flags and cid in that order.
To generate a diff of this commit:
cvs rdiff -u -r1.63 -r1.64 src/sys/dev/ic/nvme.c
Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.
Modified files:
Index: src/sys/dev/ic/nvme.c
diff -u src/sys/dev/ic/nvme.c:1.63 src/sys/dev/ic/nvme.c:1.64
--- src/sys/dev/ic/nvme.c:1.63 Mon Aug 15 10:15:59 2022
+++ src/sys/dev/ic/nvme.c Sat Aug 20 11:31:38 2022
@@ -1,4 +1,4 @@
-/* $NetBSD: nvme.c,v 1.63 2022/08/15 10:15:59 riastradh Exp $ */
+/* $NetBSD: nvme.c,v 1.64 2022/08/20 11:31:38 riastradh Exp $ */
/* $OpenBSD: nvme.c,v 1.49 2016/04/18 05:59:50 dlg Exp $ */
/*
@@ -18,7 +18,7 @@
*/
#include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: nvme.c,v 1.63 2022/08/15 10:15:59 riastradh Exp $");
+__KERNEL_RCSID(0, "$NetBSD: nvme.c,v 1.64 2022/08/20 11:31:38 riastradh Exp $");
#include <sys/param.h>
#include <sys/systm.h>
@@ -1508,6 +1508,14 @@ nvme_q_complete(struct nvme_softc *sc, s
if ((flags & NVME_CQE_PHASE) != q->q_cq_phase)
break;
+ /*
+ * Make sure we have read the flags _before_ we read
+ * the cid. Otherwise the CPU might speculatively read
+ * the cid before the entry has been assigned to our
+ * phase.
+ */
+ nvme_dmamem_sync(sc, q->q_cq_dmamem, BUS_DMASYNC_POSTREAD);
+
ccb = &q->q_ccbs[lemtoh16(&cqe->cid)];
if (++q->q_cq_head >= q->q_entries) {
