diff mbox series

[v2,6/9] net/mlx5: Use RMW accessors for changing LNKCTL

Message ID 20230517105235.29176-7-ilpo.jarvinen@linux.intel.com (mailing list archive)
State Not Applicable
Headers show
Series None | expand

Commit Message

Ilpo Järvinen May 17, 2023, 10:52 a.m. UTC
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>
Cc: stable@vger.kernel.org
---
 drivers/net/ethernet/mellanox/mlx5/core/fw_reset.c | 9 ++-------
 1 file changed, 2 insertions(+), 7 deletions(-)

Comments

Moshe Shemesh May 17, 2023, 11:18 a.m. UTC | #1
On 5/17/2023 1:52 PM, 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>
> Cc:stable@vger.kernel.org
Reviewed-by: Moshe Shemesh <moshe@nvidia.com>

Thanks!
diff mbox series

Patch

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, &reg16);
-	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;