This is a note to let you know that I've just added the patch titled mlxsw: pci: Fix driver initialization with old firmware to the 6.8-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: mlxsw-pci-fix-driver-initialization-with-old-firmwar.patch and it can be found in the queue-6.8 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit 1598939542c83586d8f0486dd3944b8240961482 Author: Ido Schimmel <idosch@xxxxxxxxxx> Date: Thu Apr 18 15:46:08 2024 +0200 mlxsw: pci: Fix driver initialization with old firmware [ Upstream commit 773501d01e6bc3f2557882a25679392d982d5f3e ] The driver queries the Management Capabilities Mask (MCAM) register during initialization to understand if a new and deeper reset flow is supported. However, not all firmware versions support this register, leading to the driver failing to load. Fix by treating an error in the register query as an indication that the feature is not supported. Fixes: f257c73e5356 ("mlxsw: pci: Add support for new reset flow") Reported-by: Tim 'mithro' Ansell <me@xxxxxxx> Signed-off-by: Ido Schimmel <idosch@xxxxxxxxxx> Reviewed-by: Petr Machata <petrm@xxxxxxxxxx> Reviewed-by: Simon Horman <horms@xxxxxxxxxx> Reviewed-by: Kalesh AP <kalesh-anakkur.purayil@xxxxxxxxxxxx> Signed-off-by: Petr Machata <petrm@xxxxxxxxxx> Link: https://lore.kernel.org/r/ee968c49d53bac96a4c66d1b09ebbd097d81aca5.1713446092.git.petrm@xxxxxxxxxx Signed-off-by: Jakub Kicinski <kuba@xxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/drivers/net/ethernet/mellanox/mlxsw/pci.c b/drivers/net/ethernet/mellanox/mlxsw/pci.c index af99bf17eb36d..f42a1b1c93687 100644 --- a/drivers/net/ethernet/mellanox/mlxsw/pci.c +++ b/drivers/net/ethernet/mellanox/mlxsw/pci.c @@ -1530,7 +1530,7 @@ mlxsw_pci_reset(struct mlxsw_pci *mlxsw_pci, const struct pci_device_id *id) { struct pci_dev *pdev = mlxsw_pci->pdev; char mcam_pl[MLXSW_REG_MCAM_LEN]; - bool pci_reset_supported; + bool pci_reset_supported = false; u32 sys_status; int err; @@ -1548,11 +1548,9 @@ mlxsw_pci_reset(struct mlxsw_pci *mlxsw_pci, const struct pci_device_id *id) mlxsw_reg_mcam_pack(mcam_pl, MLXSW_REG_MCAM_FEATURE_GROUP_ENHANCED_FEATURES); err = mlxsw_reg_query(mlxsw_pci->core, MLXSW_REG(mcam), mcam_pl); - if (err) - return err; - - mlxsw_reg_mcam_unpack(mcam_pl, MLXSW_REG_MCAM_PCI_RESET, - &pci_reset_supported); + if (!err) + mlxsw_reg_mcam_unpack(mcam_pl, MLXSW_REG_MCAM_PCI_RESET, + &pci_reset_supported); if (pci_reset_supported) { pci_dbg(pdev, "Starting PCI reset flow\n");