Don't assume that only the driver would be accessing LNKCTL of the upstream bridge. ASPM policy changes can trigger write to LNKCTL outside of driver's control.
Use RMW capability accessors which do proper locking to avoid losing concurrent updates to the register value.
Fixes: eabe8e5e88f5 ("net/mlx5: Handle sync reset now event") Suggested-by: Lukas Wunner lukas@wunner.de Signed-off-by: Ilpo Järvinen ilpo.jarvinen@linux.intel.com Reviewed-by: Moshe Shemesh moshe@nvidia.com Reviewed-by: Simon Horman simon.horman@corigine.com Cc: stable@vger.kernel.org --- drivers/net/ethernet/mellanox/mlx5/core/fw_reset.c | 9 ++------- 1 file changed, 2 insertions(+), 7 deletions(-)
diff --git a/drivers/net/ethernet/mellanox/mlx5/core/fw_reset.c b/drivers/net/ethernet/mellanox/mlx5/core/fw_reset.c index 4804990b7f22..99dcbd006357 100644 --- a/drivers/net/ethernet/mellanox/mlx5/core/fw_reset.c +++ b/drivers/net/ethernet/mellanox/mlx5/core/fw_reset.c @@ -384,16 +384,11 @@ static int mlx5_pci_link_toggle(struct mlx5_core_dev *dev) pci_cfg_access_lock(sdev); } /* PCI link toggle */ - err = pci_read_config_word(bridge, cap + PCI_EXP_LNKCTL, ®16); - if (err) - return err; - reg16 |= PCI_EXP_LNKCTL_LD; - err = pci_write_config_word(bridge, cap + PCI_EXP_LNKCTL, reg16); + err = pcie_capability_set_word(bridge, PCI_EXP_LNKCTL, PCI_EXP_LNKCTL_LD); if (err) return err; msleep(500); - reg16 &= ~PCI_EXP_LNKCTL_LD; - err = pci_write_config_word(bridge, cap + PCI_EXP_LNKCTL, reg16); + err = pcie_capability_clear_word(bridge, PCI_EXP_LNKCTL, PCI_EXP_LNKCTL_LD); if (err) return err;