diff --git a/fs/xfs/libxfs/xfs_ag_resv.c b/fs/xfs/libxfs/xfs_ag_resv.c
index fdfe6dc0d307..6c5f8d10589c 100644
--- a/fs/xfs/libxfs/xfs_ag_resv.c
+++ b/fs/xfs/libxfs/xfs_ag_resv.c
@@ -211,7 +211,11 @@ __xfs_ag_resv_init(
 		ASSERT(0);
 		return -EINVAL;
 	}
-	error = xfs_mod_fdblocks(mp, -(int64_t)hidden_space, true);
+
+	if (XFS_TEST_ERROR(false, mp, XFS_ERRTAG_AG_RESV_FAIL))
+		error = -ENOSPC;
+	else
+		error = xfs_mod_fdblocks(mp, -(int64_t)hidden_space, true);
 	if (error) {
 		trace_xfs_ag_resv_init_error(pag->pag_mount, pag->pag_agno,
 				error, _RET_IP_);
diff --git a/fs/xfs/libxfs/xfs_errortag.h b/fs/xfs/libxfs/xfs_errortag.h
index 6ca9084b6934..a23a52e643ad 100644
--- a/fs/xfs/libxfs/xfs_errortag.h
+++ b/fs/xfs/libxfs/xfs_errortag.h
@@ -58,7 +58,8 @@
 #define XFS_ERRTAG_BUF_IOERROR				35
 #define XFS_ERRTAG_REDUCE_MAX_IEXTENTS			36
 #define XFS_ERRTAG_BMAP_ALLOC_MINLEN_EXTENT		37
-#define XFS_ERRTAG_MAX					38
+#define XFS_ERRTAG_AG_RESV_FAIL				38
+#define XFS_ERRTAG_MAX					39
 
 /*
  * Random factors for above tags, 1 means always, 2 means 1/2 time, etc.
@@ -101,5 +102,6 @@
 #define XFS_RANDOM_BUF_IOERROR				XFS_RANDOM_DEFAULT
 #define XFS_RANDOM_REDUCE_MAX_IEXTENTS			1
 #define XFS_RANDOM_BMAP_ALLOC_MINLEN_EXTENT		1
+#define XFS_RANDOM_AG_RESV_FAIL				1
 
 #endif /* __XFS_ERRORTAG_H_ */
diff --git a/fs/xfs/xfs_error.c b/fs/xfs/xfs_error.c
index 4d6509a61d11..ce3bc1b291a1 100644
--- a/fs/xfs/xfs_error.c
+++ b/fs/xfs/xfs_error.c
@@ -56,6 +56,7 @@ static unsigned int xfs_errortag_random_default[] = {
 	XFS_RANDOM_BUF_IOERROR,
 	XFS_RANDOM_REDUCE_MAX_IEXTENTS,
 	XFS_RANDOM_BMAP_ALLOC_MINLEN_EXTENT,
+	XFS_RANDOM_AG_RESV_FAIL,
 };
 
 struct xfs_errortag_attr {
@@ -168,6 +169,7 @@ XFS_ERRORTAG_ATTR_RW(iunlink_fallback,	XFS_ERRTAG_IUNLINK_FALLBACK);
 XFS_ERRORTAG_ATTR_RW(buf_ioerror,	XFS_ERRTAG_BUF_IOERROR);
 XFS_ERRORTAG_ATTR_RW(reduce_max_iextents,	XFS_ERRTAG_REDUCE_MAX_IEXTENTS);
 XFS_ERRORTAG_ATTR_RW(bmap_alloc_minlen_extent,	XFS_ERRTAG_BMAP_ALLOC_MINLEN_EXTENT);
+XFS_ERRORTAG_ATTR_RW(ag_resv_fail, XFS_ERRTAG_AG_RESV_FAIL);
 
 static struct attribute *xfs_errortag_attrs[] = {
 	XFS_ERRORTAG_ATTR_LIST(noerror),
@@ -208,6 +210,7 @@ static struct attribute *xfs_errortag_attrs[] = {
 	XFS_ERRORTAG_ATTR_LIST(buf_ioerror),
 	XFS_ERRORTAG_ATTR_LIST(reduce_max_iextents),
 	XFS_ERRORTAG_ATTR_LIST(bmap_alloc_minlen_extent),
+	XFS_ERRORTAG_ATTR_LIST(ag_resv_fail),
 	NULL,
 };