| Message ID | 20230620134624.99688-8-ilpo.jarvinen@linux.intel.com |
|---|---|
| State | New |
| Headers | show |
| Series | PCI: Improve PCIe Capability RMW concurrency control | expand |
On Tue, Jun 20, 2023 at 04:46:21PM +0300, Ilpo Järvinen wrote: > 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> > Cc: stable@vger.kernel.org > --- > drivers/net/ethernet/mellanox/mlx5/core/fw_reset.c | 9 ++------- > 1 file changed, 2 insertions(+), 7 deletions(-) Reviewed-by: Simon Horman <simon.horman@corigine.com>
diff --git a/drivers/net/ethernet/mellanox/mlx5/core/fw_reset.c b/drivers/net/ethernet/mellanox/mlx5/core/fw_reset.c index 50022e7565f1..f202150a5093 100644 --- a/drivers/net/ethernet/mellanox/mlx5/core/fw_reset.c +++ b/drivers/net/ethernet/mellanox/mlx5/core/fw_reset.c @@ -332,16 +332,11 @@ 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;
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> Cc: stable@vger.kernel.org --- drivers/net/ethernet/mellanox/mlx5/core/fw_reset.c | 9 ++------- 1 file changed, 2 insertions(+), 7 deletions(-)