From: Jack Morgenstein Date: Tue, 27 Nov 2012 16:24:30 +0000 (+0000) Subject: mlx4_core: Fix potential deadlock in mlx4_eq_int() X-Git-Tag: v3.8-rc1~117^2~2^3 X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=311f813a2daefcba03f706a692fe0c67888d7622;p=platform%2Fkernel%2Flinux-3.10.git mlx4_core: Fix potential deadlock in mlx4_eq_int() The slave_state_lock spinlock is used in both interrupt context and process context, hence irq locking must be used. Found by lockdep. Signed-off-by: Jack Morgenstein Signed-off-by: Or Gerlitz Cc: Signed-off-by: Roland Dreier --- diff --git a/drivers/net/ethernet/mellanox/mlx4/cmd.c b/drivers/net/ethernet/mellanox/mlx4/cmd.c index e791e70..fdc5f23 100644 --- a/drivers/net/ethernet/mellanox/mlx4/cmd.c +++ b/drivers/net/ethernet/mellanox/mlx4/cmd.c @@ -1498,6 +1498,7 @@ static void mlx4_master_do_cmd(struct mlx4_dev *dev, int slave, u8 cmd, u32 reply; u8 is_going_down = 0; int i; + unsigned long flags; slave_state[slave].comm_toggle ^= 1; reply = (u32) slave_state[slave].comm_toggle << 31; @@ -1576,12 +1577,12 @@ static void mlx4_master_do_cmd(struct mlx4_dev *dev, int slave, u8 cmd, mlx4_warn(dev, "Bad comm cmd:%d from slave:%d\n", cmd, slave); goto reset_slave; } - spin_lock(&priv->mfunc.master.slave_state_lock); + spin_lock_irqsave(&priv->mfunc.master.slave_state_lock, flags); if (!slave_state[slave].is_slave_going_down) slave_state[slave].last_cmd = cmd; else is_going_down = 1; - spin_unlock(&priv->mfunc.master.slave_state_lock); + spin_unlock_irqrestore(&priv->mfunc.master.slave_state_lock, flags); if (is_going_down) { mlx4_warn(dev, "Slave is going down aborting command(%d)" " executing from slave:%d\n", @@ -1597,10 +1598,10 @@ static void mlx4_master_do_cmd(struct mlx4_dev *dev, int slave, u8 cmd, reset_slave: /* cleanup any slave resources */ mlx4_delete_all_resources_for_slave(dev, slave); - spin_lock(&priv->mfunc.master.slave_state_lock); + spin_lock_irqsave(&priv->mfunc.master.slave_state_lock, flags); if (!slave_state[slave].is_slave_going_down) slave_state[slave].last_cmd = MLX4_COMM_CMD_RESET; - spin_unlock(&priv->mfunc.master.slave_state_lock); + spin_unlock_irqrestore(&priv->mfunc.master.slave_state_lock, flags); /*with slave in the middle of flr, no need to clean resources again.*/ inform_slave_state: memset(&slave_state[slave].event_eq, 0, diff --git a/drivers/net/ethernet/mellanox/mlx4/eq.c b/drivers/net/ethernet/mellanox/mlx4/eq.c index c509a86..3cb7727 100644 --- a/drivers/net/ethernet/mellanox/mlx4/eq.c +++ b/drivers/net/ethernet/mellanox/mlx4/eq.c @@ -407,6 +407,7 @@ void mlx4_master_handle_slave_flr(struct work_struct *work) struct mlx4_slave_state *slave_state = priv->mfunc.master.slave_state; int i; int err; + unsigned long flags; mlx4_dbg(dev, "mlx4_handle_slave_flr\n"); @@ -418,10 +419,10 @@ void mlx4_master_handle_slave_flr(struct work_struct *work) mlx4_delete_all_resources_for_slave(dev, i); /*return the slave to running mode*/ - spin_lock(&priv->mfunc.master.slave_state_lock); + spin_lock_irqsave(&priv->mfunc.master.slave_state_lock, flags); slave_state[i].last_cmd = MLX4_COMM_CMD_RESET; slave_state[i].is_slave_going_down = 0; - spin_unlock(&priv->mfunc.master.slave_state_lock); + spin_unlock_irqrestore(&priv->mfunc.master.slave_state_lock, flags); /*notify the FW:*/ err = mlx4_cmd(dev, 0, i, 0, MLX4_CMD_INFORM_FLR_DONE, MLX4_CMD_TIME_CLASS_A, MLX4_CMD_WRAPPED); @@ -446,6 +447,7 @@ static int mlx4_eq_int(struct mlx4_dev *dev, struct mlx4_eq *eq) u8 update_slave_state; int i; enum slave_port_gen_event gen_event; + unsigned long flags; while ((eqe = next_eqe_sw(eq, dev->caps.eqe_factor))) { /* @@ -653,13 +655,13 @@ static int mlx4_eq_int(struct mlx4_dev *dev, struct mlx4_eq *eq) } else update_slave_state = 1; - spin_lock(&priv->mfunc.master.slave_state_lock); + spin_lock_irqsave(&priv->mfunc.master.slave_state_lock, flags); if (update_slave_state) { priv->mfunc.master.slave_state[flr_slave].active = false; priv->mfunc.master.slave_state[flr_slave].last_cmd = MLX4_COMM_CMD_FLR; priv->mfunc.master.slave_state[flr_slave].is_slave_going_down = 1; } - spin_unlock(&priv->mfunc.master.slave_state_lock); + spin_unlock_irqrestore(&priv->mfunc.master.slave_state_lock, flags); queue_work(priv->mfunc.master.comm_wq, &priv->mfunc.master.slave_flr_event_work); break;