Commit 052d0925 authored by Petr Machata's avatar Petr Machata Committed by Greg Kroah-Hartman

mlxsw: __mlxsw_sp_port_headroom_set(): Fix a use of local variable

[ Upstream commit 289460404f6947ef1c38e67d680be9a84161250b ]

The function-local variable "delay" enters the loop interpreted as delay
in bits. However, inside the loop it gets overwritten by the result of
mlxsw_sp_pg_buf_delay_get(), and thus leaves the loop as quantity in
cells. Thus on second and further loop iterations, the headroom for a
given priority is configured with a wrong size.

Fix by introducing a loop-local variable, delay_cells. Rename thres to
thres_cells for consistency.

Fixes: f417f04d ("mlxsw: spectrum: Refactor port buffer configuration")
Signed-off-by: default avatarPetr Machata <>
Acked-by: default avatarJiri Pirko <>
Signed-off-by: default avatarIdo Schimmel <>
Signed-off-by: default avatarDavid S. Miller <>
Signed-off-by: default avatarGreg Kroah-Hartman <>
parent 48dc41af
......@@ -1161,8 +1161,9 @@ int __mlxsw_sp_port_headroom_set(struct mlxsw_sp_port *mlxsw_sp_port, int mtu,
for (i = 0; i < IEEE_8021QAZ_MAX_TCS; i++) {
bool configure = false;
bool pfc = false;
u16 thres_cells;
u16 delay_cells;
bool lossy;
u16 thres;
for (j = 0; j < IEEE_8021QAZ_MAX_TCS; j++) {
if (prio_tc[j] == i) {
......@@ -1176,10 +1177,11 @@ int __mlxsw_sp_port_headroom_set(struct mlxsw_sp_port *mlxsw_sp_port, int mtu,
lossy = !(pfc || pause_en);
thres = mlxsw_sp_pg_buf_threshold_get(mlxsw_sp, mtu);
delay = mlxsw_sp_pg_buf_delay_get(mlxsw_sp, mtu, delay, pfc,
mlxsw_sp_pg_buf_pack(pbmc_pl, i, thres + delay, thres, lossy);
thres_cells = mlxsw_sp_pg_buf_threshold_get(mlxsw_sp, mtu);
delay_cells = mlxsw_sp_pg_buf_delay_get(mlxsw_sp, mtu, delay,
pfc, pause_en);
mlxsw_sp_pg_buf_pack(pbmc_pl, i, thres_cells + delay_cells,
thres_cells, lossy);
return mlxsw_reg_write(mlxsw_sp->core, MLXSW_REG(pbmc), pbmc_pl);
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