From: Huy Nguyen Date: Wed, 4 Oct 2017 22:58:21 +0000 (-0500) Subject: net/mlx5: Delay events till mlx5 interface's add complete for pci resume X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=4ca637a20a524cd8ddbca696f12bfa92111c96e3;p=GitHub%2FLineageOS%2Fandroid_kernel_motorola_exynos9610.git net/mlx5: Delay events till mlx5 interface's add complete for pci resume mlx5_ib_add is called during mlx5_pci_resume after a pci error. Before mlx5_ib_add completes, there are multiple events which trigger function mlx5_ib_event. This cause kernel panic because mlx5_ib_event accesses unitialized resources. The fix is to extend Erez Shitrit's patch <97834eba7c19> ("net/mlx5: Delay events till ib registration ends") to cover the pci resume code path. Trace: mlx5_core 0001:01:00.6: mlx5_pci_resume was called mlx5_core 0001:01:00.6: firmware version: 16.20.1011 mlx5_core 0001:01:00.6: mlx5_attach_interface:164:(pid 779): mlx5_ib_event:2996:(pid 34777): warning: event on port 1 mlx5_ib_event:2996:(pid 34782): warning: event on port 1 Unable to handle kernel paging request for data at address 0x0001c104 Faulting instruction address: 0xd000000008f411fc Oops: Kernel access of bad area, sig: 11 [#1] ... ... Call Trace: [c000000fff77bb70] [d000000008f4119c] mlx5_ib_event+0x64/0x470 [mlx5_ib] (unreliable) [c000000fff77bc60] [d000000008e67130] mlx5_core_event+0xb8/0x210 [mlx5_core] [c000000fff77bd10] [d000000008e4bd00] mlx5_eq_int+0x528/0x860[mlx5_core] Fixes: 97834eba7c19 ("net/mlx5: Delay events till ib registration ends") Signed-off-by: Huy Nguyen Reviewed-by: Saeed Mahameed Signed-off-by: Saeed Mahameed --- diff --git a/drivers/net/ethernet/mellanox/mlx5/core/dev.c b/drivers/net/ethernet/mellanox/mlx5/core/dev.c index ff60cf7342ca..fc281712869b 100644 --- a/drivers/net/ethernet/mellanox/mlx5/core/dev.c +++ b/drivers/net/ethernet/mellanox/mlx5/core/dev.c @@ -77,35 +77,41 @@ static void add_delayed_event(struct mlx5_priv *priv, list_add_tail(&delayed_event->list, &priv->waiting_events_list); } -static void fire_delayed_event_locked(struct mlx5_device_context *dev_ctx, - struct mlx5_core_dev *dev, - struct mlx5_priv *priv) +static void delayed_event_release(struct mlx5_device_context *dev_ctx, + struct mlx5_priv *priv) { + struct mlx5_core_dev *dev = container_of(priv, struct mlx5_core_dev, priv); struct mlx5_delayed_event *de; struct mlx5_delayed_event *n; + struct list_head temp; - /* stop delaying events */ - priv->is_accum_events = false; + INIT_LIST_HEAD(&temp); + + spin_lock_irq(&priv->ctx_lock); - /* fire all accumulated events before new event comes */ - list_for_each_entry_safe(de, n, &priv->waiting_events_list, list) { + priv->is_accum_events = false; + list_splice_init(&priv->waiting_events_list, &temp); + if (!dev_ctx->context) + goto out; + list_for_each_entry_safe(de, n, &priv->waiting_events_list, list) dev_ctx->intf->event(dev, dev_ctx->context, de->event, de->param); + +out: + spin_unlock_irq(&priv->ctx_lock); + + list_for_each_entry_safe(de, n, &temp, list) { list_del(&de->list); kfree(de); } } -static void cleanup_delayed_evets(struct mlx5_priv *priv) +/* accumulating events that can come after mlx5_ib calls to + * ib_register_device, till adding that interface to the events list. + */ +static void delayed_event_start(struct mlx5_priv *priv) { - struct mlx5_delayed_event *de; - struct mlx5_delayed_event *n; - spin_lock_irq(&priv->ctx_lock); - priv->is_accum_events = false; - list_for_each_entry_safe(de, n, &priv->waiting_events_list, list) { - list_del(&de->list); - kfree(de); - } + priv->is_accum_events = true; spin_unlock_irq(&priv->ctx_lock); } @@ -122,11 +128,8 @@ void mlx5_add_device(struct mlx5_interface *intf, struct mlx5_priv *priv) return; dev_ctx->intf = intf; - /* accumulating events that can come after mlx5_ib calls to - * ib_register_device, till adding that interface to the events list. - */ - priv->is_accum_events = true; + delayed_event_start(priv); dev_ctx->context = intf->add(dev); set_bit(MLX5_INTERFACE_ADDED, &dev_ctx->state); @@ -137,8 +140,6 @@ void mlx5_add_device(struct mlx5_interface *intf, struct mlx5_priv *priv) spin_lock_irq(&priv->ctx_lock); list_add_tail(&dev_ctx->list, &priv->ctx_list); - fire_delayed_event_locked(dev_ctx, dev, priv); - #ifdef CONFIG_INFINIBAND_ON_DEMAND_PAGING if (dev_ctx->intf->pfault) { if (priv->pfault) { @@ -150,11 +151,12 @@ void mlx5_add_device(struct mlx5_interface *intf, struct mlx5_priv *priv) } #endif spin_unlock_irq(&priv->ctx_lock); - } else { - kfree(dev_ctx); - /* delete all accumulated events */ - cleanup_delayed_evets(priv); } + + delayed_event_release(dev_ctx, priv); + + if (!dev_ctx->context) + kfree(dev_ctx); } static struct mlx5_device_context *mlx5_get_device(struct mlx5_interface *intf, @@ -205,17 +207,21 @@ static void mlx5_attach_interface(struct mlx5_interface *intf, struct mlx5_priv if (!dev_ctx) return; + delayed_event_start(priv); if (intf->attach) { if (test_bit(MLX5_INTERFACE_ATTACHED, &dev_ctx->state)) - return; + goto out; intf->attach(dev, dev_ctx->context); set_bit(MLX5_INTERFACE_ATTACHED, &dev_ctx->state); } else { if (test_bit(MLX5_INTERFACE_ADDED, &dev_ctx->state)) - return; + goto out; dev_ctx->context = intf->add(dev); set_bit(MLX5_INTERFACE_ADDED, &dev_ctx->state); } + +out: + delayed_event_release(dev_ctx, priv); } void mlx5_attach_device(struct mlx5_core_dev *dev) @@ -414,8 +420,14 @@ void mlx5_core_event(struct mlx5_core_dev *dev, enum mlx5_dev_event event, if (priv->is_accum_events) add_delayed_event(priv, dev, event, param); + /* After mlx5_detach_device, the dev_ctx->intf is still set and dev_ctx is + * still in priv->ctx_list. In this case, only notify the dev_ctx if its + * ADDED or ATTACHED bit are set. + */ list_for_each_entry(dev_ctx, &priv->ctx_list, list) - if (dev_ctx->intf->event) + if (dev_ctx->intf->event && + (test_bit(MLX5_INTERFACE_ADDED, &dev_ctx->state) || + test_bit(MLX5_INTERFACE_ATTACHED, &dev_ctx->state))) dev_ctx->intf->event(dev, dev_ctx->context, event, param); spin_unlock_irqrestore(&priv->ctx_lock, flags);