[PATCH AUTOSEL 5.2 143/171] rds: Accept peer connection reject messages due to incompatible version

[PATCH AUTOSEL 5.2 143/171] rds: Accept peer connection reject messages due to incompatible version

[Sasha Levin]

From: Gerd Rausch <gerd.rausch@oracle.com>

[ Upstream commit 8c6166cfc9cd48e93d9176561e50b63cef4330d5 ]

Prior to
commit d021fabf525ff ("rds: rdma: add consumer reject")

function "rds_rdma_cm_event_handler_cmn" would always honor a rejected
connection attempt by issuing a "rds_conn_drop".

The commit mentioned above added a "break", eliminating
the "fallthrough" case and made the "rds_conn_drop" rather conditional:

Now it only happens if a "consumer defined" reject (i.e. "rdma_reject")
carries an integer-value of "1" inside "private_data":

  if (!conn)
    break;
    err = (int *)rdma_consumer_reject_data(cm_id, event, &len);
    if (!err || (err && ((*err) == RDS_RDMA_REJ_INCOMPAT))) {
      pr_warn("RDS/RDMA: conn <%pI6c, %pI6c> rejected, dropping connection\n",
              &conn->c_laddr, &conn->c_faddr);
              conn->c_proposed_version = RDS_PROTOCOL_COMPAT_VERSION;
              rds_conn_drop(conn);
    }
    rdsdebug("Connection rejected: %s\n",
             rdma_reject_msg(cm_id, event->status));
    break;
    /* FALLTHROUGH */
A number of issues are worth mentioning here:
   #1) Previous versions of the RDS code simply rejected a connection
       by calling "rdma_reject(cm_id, NULL, 0);"
       So the value of the payload in "private_data" will not be "1",
       but "0".

   #2) Now the code has become dependent on host byte order and sizing.
       If one peer is big-endian, the other is little-endian,
       or there's a difference in sizeof(int) (e.g. ILP64 vs LP64),
       the *err check does not work as intended.

   #3) There is no check for "len" to see if the data behind *err is even valid.
       Luckily, it appears that the "rdma_reject(cm_id, NULL, 0)" will always
       carry 148 bytes of zeroized payload.
       But that should probably not be relied upon here.

   #4) With the added "break;",
       we might as well drop the misleading "/* FALLTHROUGH */" comment.

This commit does _not_ address issue #2, as the sender would have to
agree on a byte order as well.

Here is the sequence of messages in this observed error-scenario:
   Host-A is pre-QoS changes (excluding the commit mentioned above)
   Host-B is post-QoS changes (including the commit mentioned above)

   #1 Host-B
      issues a connection request via function "rds_conn_path_transition"
      connection state transitions to "RDS_CONN_CONNECTING"

   #2 Host-A
      rejects the incompatible connection request (from #1)
      It does so by calling "rdma_reject(cm_id, NULL, 0);"

   #3 Host-B
      receives an "RDMA_CM_EVENT_REJECTED" event (from #2)
      But since the code is changed in the way described above,
      it won't drop the connection here, simply because "*err == 0".

   #4 Host-A
      issues a connection request

   #5 Host-B
      receives an "RDMA_CM_EVENT_CONNECT_REQUEST" event
      and ends up calling "rds_ib_cm_handle_connect".
      But since the state is already in "RDS_CONN_CONNECTING"
      (as of #1) it will end up issuing a "rdma_reject" without
      dropping the connection:
         if (rds_conn_state(conn) == RDS_CONN_CONNECTING) {
             /* Wait and see - our connect may still be succeeding */
             rds_ib_stats_inc(s_ib_connect_raced);
         }
         goto out;

   #6 Host-A
      receives an "RDMA_CM_EVENT_REJECTED" event (from #5),
      drops the connection and tries again (goto #4) until it gives up.

Tested-by: Zhu Yanjun <yanjun.zhu@oracle.com>
Signed-off-by: Gerd Rausch <gerd.rausch@oracle.com>
Signed-off-by: Santosh Shilimkar <santosh.shilimkar@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 net/rds/rdma_transport.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/net/rds/rdma_transport.c b/net/rds/rdma_transport.c
index 46bce8389066..9db455d02255 100644
--- a/net/rds/rdma_transport.c
+++ b/net/rds/rdma_transport.c
@@ -112,7 +112,9 @@ static int rds_rdma_cm_event_handler_cmn(struct rdma_cm_id *cm_id,
 		if (!conn)
 			break;
 		err = (int *)rdma_consumer_reject_data(cm_id, event, &len);
-		if (!err || (err && ((*err) == RDS_RDMA_REJ_INCOMPAT))) {
+		if (!err ||
+		    (err && len >= sizeof(*err) &&
+		     ((*err) <= RDS_RDMA_REJ_INCOMPAT))) {
 			pr_warn("RDS/RDMA: conn <%pI6c, %pI6c> rejected, dropping connection\n",
 				&conn->c_laddr, &conn->c_faddr);
 			conn->c_proposed_version = RDS_PROTOCOL_COMPAT_VERSION;
@@ -122,7 +124,6 @@ static int rds_rdma_cm_event_handler_cmn(struct rdma_cm_id *cm_id,
 		rdsdebug("Connection rejected: %s\n",
 			 rdma_reject_msg(cm_id, event->status));
 		break;
-		/* FALLTHROUGH */
 	case RDMA_CM_EVENT_ADDR_ERROR:
 	case RDMA_CM_EVENT_ROUTE_ERROR:
 	case RDMA_CM_EVENT_CONNECT_ERROR:
-- 
2.20.1

[PATCH AUTOSEL 5.2 150/171] net/mlx5e: IPoIB, Add error path in mlx5_rdma_setup_rn

[Sasha Levin]

From: Aya Levin <ayal@mellanox.com>

[ Upstream commit ef1ce7d7b67b46661091c7ccc0396186b7a247ef ]

Check return value from mlx5e_attach_netdev, add error path on failure.

Fixes: 48935bbb7ae8 ("net/mlx5e: IPoIB, Add netdevice profile skeleton")
Signed-off-by: Aya Levin <ayal@mellanox.com>
Reviewed-by: Feras Daoud <ferasda@mellanox.com>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/net/ethernet/mellanox/mlx5/core/ipoib/ipoib.c | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/mellanox/mlx5/core/ipoib/ipoib.c b/drivers/net/ethernet/mellanox/mlx5/core/ipoib/ipoib.c
index 9ca492b430d8..603d294757b4 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/ipoib/ipoib.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/ipoib/ipoib.c
@@ -698,7 +698,9 @@ static int mlx5_rdma_setup_rn(struct ib_device *ibdev, u8 port_num,
 
 	prof->init(mdev, netdev, prof, ipriv);
 
-	mlx5e_attach_netdev(epriv);
+	err = mlx5e_attach_netdev(epriv);
+	if (err)
+		goto detach;
 	netif_carrier_off(netdev);
 
 	/* set rdma_netdev func pointers */
@@ -714,6 +716,11 @@ static int mlx5_rdma_setup_rn(struct ib_device *ibdev, u8 port_num,
 
 	return 0;
 
+detach:
+	prof->cleanup(epriv);
+	if (ipriv->sub_interface)
+		return err;
+	mlx5e_destroy_mdev_resources(mdev);
 destroy_ht:
 	mlx5i_pkey_qpn_ht_cleanup(netdev);
 	return err;
-- 
2.20.1

[PATCH AUTOSEL 5.2 155/171] net/mlx5: E-Switch, Fix default encap mode

[Sasha Levin]

From: Maor Gottlieb <maorg@mellanox.com>

[ Upstream commit 9a64144d683a4395f57562d90247c61a0bf5105f ]

Encap mode is related to switchdev mode only. Move the init of
the encap mode to eswitch_offloads. Before this change, we reported
that eswitch supports encap, even tough the device was in non
SRIOV mode.

Fixes: 7768d1971de67 ('net/mlx5: E-Switch, Add control for encapsulation')
Signed-off-by: Maor Gottlieb <maorg@mellanox.com>
Reviewed-by: Roi Dayan <roid@mellanox.com>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/net/ethernet/mellanox/mlx5/core/eswitch.c          | 5 -----
 drivers/net/ethernet/mellanox/mlx5/core/eswitch_offloads.c | 7 +++++++
 2 files changed, 7 insertions(+), 5 deletions(-)

diff --git a/drivers/net/ethernet/mellanox/mlx5/core/eswitch.c b/drivers/net/ethernet/mellanox/mlx5/core/eswitch.c
index 6a921e24cd5e..e9339e7d6a18 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/eswitch.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/eswitch.c
@@ -1882,11 +1882,6 @@ int mlx5_eswitch_init(struct mlx5_core_dev *dev)
 	esw->enabled_vports = 0;
 	esw->mode = SRIOV_NONE;
 	esw->offloads.inline_mode = MLX5_INLINE_MODE_NONE;
-	if (MLX5_CAP_ESW_FLOWTABLE_FDB(dev, reformat) &&
-	    MLX5_CAP_ESW_FLOWTABLE_FDB(dev, decap))
-		esw->offloads.encap = DEVLINK_ESWITCH_ENCAP_MODE_BASIC;
-	else
-		esw->offloads.encap = DEVLINK_ESWITCH_ENCAP_MODE_NONE;
 
 	dev->priv.eswitch = esw;
 	return 0;
diff --git a/drivers/net/ethernet/mellanox/mlx5/core/eswitch_offloads.c b/drivers/net/ethernet/mellanox/mlx5/core/eswitch_offloads.c
index 47b446d30f71..c2beadc41c40 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/eswitch_offloads.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/eswitch_offloads.c
@@ -1840,6 +1840,12 @@ int esw_offloads_init(struct mlx5_eswitch *esw, int vf_nvports,
 {
 	int err;
 
+	if (MLX5_CAP_ESW_FLOWTABLE_FDB(esw->dev, reformat) &&
+	    MLX5_CAP_ESW_FLOWTABLE_FDB(esw->dev, decap))
+		esw->offloads.encap = DEVLINK_ESWITCH_ENCAP_MODE_BASIC;
+	else
+		esw->offloads.encap = DEVLINK_ESWITCH_ENCAP_MODE_NONE;
+
 	err = esw_offloads_steering_init(esw, vf_nvports, total_nvports);
 	if (err)
 		return err;
@@ -1901,6 +1907,7 @@ void esw_offloads_cleanup(struct mlx5_eswitch *esw)
 	esw_offloads_devcom_cleanup(esw);
 	esw_offloads_unload_all_reps(esw, num_vfs);
 	esw_offloads_steering_cleanup(esw);
+	esw->offloads.encap = DEVLINK_ESWITCH_ENCAP_MODE_NONE;
 }
 
 static int esw_mode_from_devlink(u16 mode, u16 *mlx5_mode)
-- 
2.20.1

[PATCH AUTOSEL 5.2 167/171] cxgb4: reduce kernel stack usage in cudbg_collect_mem_region()

[Sasha Levin]

From: Arnd Bergmann <arnd@arndb.de>

[ Upstream commit 752c2ea2d8e7c23b0f64e2e7d4337f3604d44c9f ]

The cudbg_collect_mem_region() and cudbg_read_fw_mem() both use several
hundred kilobytes of kernel stack space. One gets inlined into the other,
which causes the stack usage to be combined beyond the warning limit
when building with clang:

drivers/net/ethernet/chelsio/cxgb4/cudbg_lib.c:1057:12: error: stack frame size of 1244 bytes in function 'cudbg_collect_mem_region' [-Werror,-Wframe-larger-than=]

Restructuring cudbg_collect_mem_region() lets clang do the same
optimization that gcc does and reuse the stack slots as it can
see that the large variables are never used together.

A better fix might be to avoid using cudbg_meminfo on the stack
altogether, but that requires a larger rewrite.

Fixes: a1c69520f785 ("cxgb4: collect MC memory dump")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 .../net/ethernet/chelsio/cxgb4/cudbg_lib.c    | 19 +++++++++++++------
 1 file changed, 13 insertions(+), 6 deletions(-)

diff --git a/drivers/net/ethernet/chelsio/cxgb4/cudbg_lib.c b/drivers/net/ethernet/chelsio/cxgb4/cudbg_lib.c
index a76529a7662d..c2e92786608b 100644
--- a/drivers/net/ethernet/chelsio/cxgb4/cudbg_lib.c
+++ b/drivers/net/ethernet/chelsio/cxgb4/cudbg_lib.c
@@ -1054,14 +1054,12 @@ static void cudbg_t4_fwcache(struct cudbg_init *pdbg_init,
 	}
 }
 
-static int cudbg_collect_mem_region(struct cudbg_init *pdbg_init,
-				    struct cudbg_buffer *dbg_buff,
-				    struct cudbg_error *cudbg_err,
-				    u8 mem_type)
+static unsigned long cudbg_mem_region_size(struct cudbg_init *pdbg_init,
+					   struct cudbg_error *cudbg_err,
+					   u8 mem_type)
 {
 	struct adapter *padap = pdbg_init->adap;
 	struct cudbg_meminfo mem_info;
-	unsigned long size;
 	u8 mc_idx;
 	int rc;
 
@@ -1075,7 +1073,16 @@ static int cudbg_collect_mem_region(struct cudbg_init *pdbg_init,
 	if (rc)
 		return rc;
 
-	size = mem_info.avail[mc_idx].limit - mem_info.avail[mc_idx].base;
+	return mem_info.avail[mc_idx].limit - mem_info.avail[mc_idx].base;
+}
+
+static int cudbg_collect_mem_region(struct cudbg_init *pdbg_init,
+				    struct cudbg_buffer *dbg_buff,
+				    struct cudbg_error *cudbg_err,
+				    u8 mem_type)
+{
+	unsigned long size = cudbg_mem_region_size(pdbg_init, cudbg_err, mem_type);
+
 	return cudbg_read_fw_mem(pdbg_init, dbg_buff, mem_type, size,
 				 cudbg_err);
 }
-- 
2.20.1