From 924d1ab98706f7c66a40c94579c034dcea1d5789 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Ilpo=20J=C3=A4rvinen?= Date: Mon, 17 Jul 2023 15:04:59 +0300 Subject: [PATCH] net/mlx5: Use RMW accessors for changing LNKCTL MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit [ Upstream commit 30de872537bda526664d7a20b646adfb3e7ce6e6 ] 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. Suggested-by: Lukas Wunner Fixes: eabe8e5e88f5 ("net/mlx5: Handle sync reset now event") Link: https://lore.kernel.org/r/20230717120503.15276-8-ilpo.jarvinen@linux.intel.com Signed-off-by: Ilpo Järvinen Signed-off-by: Bjorn Helgaas Reviewed-by: Moshe Shemesh Reviewed-by: Simon Horman Signed-off-by: Sasha Levin --- 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 e29db4c39b37..a2d9904e1049 100644 --- a/drivers/net/ethernet/mellanox/mlx5/core/fw_reset.c +++ b/drivers/net/ethernet/mellanox/mlx5/core/fw_reset.c @@ -279,16 +279,11 @@ 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;