releases/6.1.104/net-mlx5-fix-missing-lock-on-sync-reset-reload.patch

From d0a4b9ed662c720cb49c4ab553c8030e667880cf Mon Sep 17 00:00:00 2001
From: Sasha Levin <sashal@kernel.org>
Date: Tue, 30 Jul 2024 09:16:34 +0300
Subject: net/mlx5: Fix missing lock on sync reset reload
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From: Moshe Shemesh <moshe@nvidia.com>

[ Upstream commit 572f9caa9e7295f8c8822e4122c7ae8f1c412ff9 ]

On sync reset reload work, when remote host updates devlink on reload
actions performed on that host, it misses taking devlink lock before
calling devlink_remote_reload_actions_performed() which results in
triggering lock assert like the following:

WARNING: CPU: 4 PID: 1164 at net/devlink/core.c:261 devl_assert_locked+0x3e/0x50
…
 CPU: 4 PID: 1164 Comm: kworker/u96:6 Tainted: G S      W          6.10.0-rc2+ #116
 Hardware name: Supermicro SYS-2028TP-DECTR/X10DRT-PT, BIOS 2.0 12/18/2015
 Workqueue: mlx5_fw_reset_events mlx5_sync_reset_reload_work [mlx5_core]
 RIP: 0010:devl_assert_locked+0x3e/0x50
…
 Call Trace:
  <TASK>
  ? __warn+0xa4/0x210
  ? devl_assert_locked+0x3e/0x50
  ? report_bug+0x160/0x280
  ? handle_bug+0x3f/0x80
  ? exc_invalid_op+0x17/0x40
  ? asm_exc_invalid_op+0x1a/0x20
  ? devl_assert_locked+0x3e/0x50
  devlink_notify+0x88/0x2b0
  ? mlx5_attach_device+0x20c/0x230 [mlx5_core]
  ? __pfx_devlink_notify+0x10/0x10
  ? process_one_work+0x4b6/0xbb0
  process_one_work+0x4b6/0xbb0
[…]

Fixes: 84a433a40d0e ("net/mlx5: Lock mlx5 devlink reload callbacks")
Signed-off-by: Moshe Shemesh <moshe@nvidia.com>
Reviewed-by: Maor Gottlieb <maorg@nvidia.com>
Signed-off-by: Tariq Toukan <tariqt@nvidia.com>
Reviewed-by: Wojciech Drewek <wojciech.drewek@intel.com>
Link: https://patch.msgid.link/20240730061638.1831002-6-tariqt@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/net/ethernet/mellanox/mlx5/core/fw_reset.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/mellanox/mlx5/core/fw_reset.c b/drivers/net/ethernet/mellanox/mlx5/core/fw_reset.c
index dec1492da74de..1a818759a9aac 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/fw_reset.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/fw_reset.c
@@ -145,6 +145,7 @@ int mlx5_fw_reset_set_live_patch(struct mlx5_core_dev *dev)
 static void mlx5_fw_reset_complete_reload(struct mlx5_core_dev *dev)
 {
 	struct mlx5_fw_reset *fw_reset = dev->priv.fw_reset;
+	struct devlink *devlink = priv_to_devlink(dev);
 
 	/* if this is the driver that initiated the fw reset, devlink completed the reload */
 	if (test_bit(MLX5_FW_RESET_FLAGS_PENDING_COMP, &fw_reset->reset_flags)) {
@@ -155,9 +156,11 @@ static void mlx5_fw_reset_complete_reload(struct mlx5_core_dev *dev)
 			mlx5_core_err(dev, "reset reload flow aborted, PCI reads still not working\n");
 		else
 			mlx5_load_one(dev, true);
-		devlink_remote_reload_actions_performed(priv_to_devlink(dev), 0,
+		devl_lock(devlink);
+		devlink_remote_reload_actions_performed(devlink, 0,
 							BIT(DEVLINK_RELOAD_ACTION_DRIVER_REINIT) |
 							BIT(DEVLINK_RELOAD_ACTION_FW_ACTIVATE));
+		devl_unlock(devlink);
 	}
 }
 
-- 
2.43.0