| Message ID | 20201005090912.424121-3-vladimir.oltean@nxp.com |
|---|---|
| State | Accepted |
| Delegated to: | David Miller |
| Headers | show |
| Series | Fix tail dropping watermarks for Ocelot switches | expand |
diff --git a/drivers/net/dsa/ocelot/felix_vsc9959.c b/drivers/net/dsa/ocelot/felix_vsc9959.c index 4fc67ff212de..cb0f3d28ecac 100644 --- a/drivers/net/dsa/ocelot/felix_vsc9959.c +++ b/drivers/net/dsa/ocelot/felix_vsc9959.c @@ -998,6 +998,8 @@ static int vsc9959_prevalidate_phy_mode(struct ocelot *ocelot, int port, */ static u16 vsc9959_wm_enc(u16 value) { + WARN_ON(value >= 16 * BIT(8)); + if (value >= BIT(8)) return BIT(8) | (value / 16); diff --git a/drivers/net/dsa/ocelot/seville_vsc9953.c b/drivers/net/dsa/ocelot/seville_vsc9953.c index e993f3eac3eb..76576cf0ba8a 100644 --- a/drivers/net/dsa/ocelot/seville_vsc9953.c +++ b/drivers/net/dsa/ocelot/seville_vsc9953.c @@ -1049,6 +1049,8 @@ static int vsc9953_prevalidate_phy_mode(struct ocelot *ocelot, int port, */ static u16 vsc9953_wm_enc(u16 value) { + WARN_ON(value >= 16 * BIT(9)); + if (value >= BIT(9)) return BIT(9) | (value / 16); diff --git a/drivers/net/ethernet/mscc/ocelot_vsc7514.c b/drivers/net/ethernet/mscc/ocelot_vsc7514.c index f3e54589e6d6..79b88bc69c75 100644 --- a/drivers/net/ethernet/mscc/ocelot_vsc7514.c +++ b/drivers/net/ethernet/mscc/ocelot_vsc7514.c @@ -754,6 +754,8 @@ static int ocelot_reset(struct ocelot *ocelot) */ static u16 ocelot_wm_enc(u16 value) { + WARN_ON(value >= 16 * BIT(8)); + if (value >= BIT(8)) return BIT(8) | (value / 16);
There is an upper bound to the value that a watermark may hold. That upper bound is not immediately obvious during configuration, and it might be possible to have accidental truncation. Actually this has happened already, add a warning to prevent it from happening again. Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> --- drivers/net/dsa/ocelot/felix_vsc9959.c | 2 ++ drivers/net/dsa/ocelot/seville_vsc9953.c | 2 ++ drivers/net/ethernet/mscc/ocelot_vsc7514.c | 2 ++ 3 files changed, 6 insertions(+)