6.6-stable review patch. If anyone has any objections, please let me know.
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From: Shay Drory shayd@nvidia.com
[ Upstream commit 79a0e32b32ac4e4f9e4bb22be97f371c8c116c88 ]
The reclaim_pages_cmd() function sends a command to the firmware to reclaim pages if the command interface is active.
A race condition can occur if the command interface goes down (e.g., due to a PCI error) while the mlx5_cmd_do() call is in flight. In this case, mlx5_cmd_do() will return an error. The original code would propagate this error immediately, bypassing the software-based page reclamation logic that is supposed to run when the command interface is down.
Fix this by checking whether mlx5_cmd_do() returns -ENXIO, which mark that command interface is down. If this is the case, fall through to the software reclamation path. If the command failed for any another reason, or finished successfully, return as before.
Fixes: b898ce7bccf1 ("net/mlx5: cmdif, Avoid skipping reclaim pages if FW is not accessible") Signed-off-by: Shay Drory shayd@nvidia.com Reviewed-by: Moshe Shemesh moshe@nvidia.com Signed-off-by: Tariq Toukan 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/pagealloc.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-)
diff --git a/drivers/net/ethernet/mellanox/mlx5/core/pagealloc.c b/drivers/net/ethernet/mellanox/mlx5/core/pagealloc.c index e0581c6f9cecd..5df1472fe2be2 100644 --- a/drivers/net/ethernet/mellanox/mlx5/core/pagealloc.c +++ b/drivers/net/ethernet/mellanox/mlx5/core/pagealloc.c @@ -489,9 +489,12 @@ static int reclaim_pages_cmd(struct mlx5_core_dev *dev, u32 func_id; u32 npages; u32 i = 0; + int err;
- if (!mlx5_cmd_is_down(dev)) - return mlx5_cmd_do(dev, in, in_size, out, out_size); + err = mlx5_cmd_do(dev, in, in_size, out, out_size); + /* If FW is gone (-ENXIO), proceed to forceful reclaim */ + if (err != -ENXIO) + return err;
/* No hard feelings, we want our pages back! */ npages = MLX5_GET(manage_pages_in, in, input_num_entries);