6.6-stable review patch. If anyone has any objections, please let me know.
------------------
From: En-Wei Wu en-wei.wu@canonical.com
[ Upstream commit bd2776e39c2a82ef4681d02678bb77b3d41e79be ]
When booting with a dock connected, the igc driver may get stuck for ~40 seconds if PCIe link is lost during initialization.
This happens because the driver access device after EECD register reads return all F's, indicating failed reads. Consequently, hw->hw_addr is set to NULL, which impacts subsequent rd32() reads. This leads to the driver hanging in igc_get_hw_semaphore_i225(), as the invalid hw->hw_addr prevents retrieving the expected value.
To address this, a validation check and a corresponding return value catch is added for the EECD register read result. If all F's are returned, indicating PCIe link loss, the driver will return -ENXIO immediately. This avoids the 40-second hang and significantly improves boot time when using a dock with an igc NIC.
Log before the patch: [ 0.911913] igc 0000:70:00.0: enabling device (0000 -> 0002) [ 0.912386] igc 0000:70:00.0: PTM enabled, 4ns granularity [ 1.571098] igc 0000:70:00.0 (unnamed net_device) (uninitialized): PCIe link lost, device now detached [ 43.449095] igc_get_hw_semaphore_i225: igc 0000:70:00.0 (unnamed net_device) (uninitialized): Driver can't access device - SMBI bit is set. [ 43.449186] igc 0000:70:00.0: probe with driver igc failed with error -13 [ 46.345701] igc 0000:70:00.0: enabling device (0000 -> 0002) [ 46.345777] igc 0000:70:00.0: PTM enabled, 4ns granularity
Log after the patch: [ 1.031000] igc 0000:70:00.0: enabling device (0000 -> 0002) [ 1.032097] igc 0000:70:00.0: PTM enabled, 4ns granularity [ 1.642291] igc 0000:70:00.0 (unnamed net_device) (uninitialized): PCIe link lost, device now detached [ 5.480490] igc 0000:70:00.0: enabling device (0000 -> 0002) [ 5.480516] igc 0000:70:00.0: PTM enabled, 4ns granularity
Fixes: ab4056126813 ("igc: Add NVM support") Cc: Chia-Lin Kao (AceLan) acelan.kao@canonical.com Signed-off-by: En-Wei Wu en-wei.wu@canonical.com Reviewed-by: Vitaly Lifshits vitaly.lifshits@intel.com Tested-by: Mor Bar-Gabay morx.bar.gabay@intel.com Signed-off-by: Tony Nguyen anthony.l.nguyen@intel.com Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/net/ethernet/intel/igc/igc_base.c | 6 ++++++ 1 file changed, 6 insertions(+)
diff --git a/drivers/net/ethernet/intel/igc/igc_base.c b/drivers/net/ethernet/intel/igc/igc_base.c index 9fae8bdec2a7..1613b562d17c 100644 --- a/drivers/net/ethernet/intel/igc/igc_base.c +++ b/drivers/net/ethernet/intel/igc/igc_base.c @@ -68,6 +68,10 @@ static s32 igc_init_nvm_params_base(struct igc_hw *hw) u32 eecd = rd32(IGC_EECD); u16 size;
+ /* failed to read reg and got all F's */ + if (!(~eecd)) + return -ENXIO; + size = FIELD_GET(IGC_EECD_SIZE_EX_MASK, eecd);
/* Added to a constant, "size" becomes the left-shift value @@ -221,6 +225,8 @@ static s32 igc_get_invariants_base(struct igc_hw *hw)
/* NVM initialization */ ret_val = igc_init_nvm_params_base(hw); + if (ret_val) + goto out; switch (hw->mac.type) { case igc_i225: ret_val = igc_init_nvm_params_i225(hw);