* Re: [PATCH net 3/3] igc: return early when failing to read EECD register [not found] <20250107190150.1758577-4-anthony.l.nguyen@intel.com> @ 2025-04-18 19:34 ` Bjorn Helgaas 2025-04-22 17:16 ` Tony Nguyen 0 siblings, 1 reply; 3+ messages in thread From: Bjorn Helgaas @ 2025-04-18 19:34 UTC (permalink / raw) To: Tony Nguyen Cc: davem, kuba, pabeni, edumazet, andrew+netdev, netdev, En-Wei Wu, vitaly.lifshits, dima.ruinskiy, Chia-Lin Kao (AceLan), Mor Bar-Gabay, Kalesh AP, Przemek Kitszel, linux-pci [+cc Kalesh, Przemek, linux-pci] On Tue, Jan 07, 2025 at 11:01:47AM -0800, Tony Nguyen wrote: > From: En-Wei Wu <en-wei.wu@canonical.com> > > 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> > --- > 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; I don't understand this. It looks like a band-aid that makes boot faster but doesn't solve the real problem. In its defense, I guess that with this patch, the first igc probe fails, and then for some reason we attempt another a few seconds later, and the second igc probe works fine, so the NIC actually does end up working correct, right? I think the PCI core has some issues with configuring ASPM L1.2, and I wonder if those are relevant here. If somebody can repro the problem (i.e., without this patch, which looks like it appeared in v6.13 as bd2776e39c2a ("igc: return early when failing to read EECD register")), I wonder if you could try booting with "pcie_port_pm=off pcie_aspm.policy=performance" and see if that also avoids the problem? If so, I'd like to see the dmesg log with "pci=earlydump" and the "sudo lspci -vv" output when booted with and without "pcie_port_pm=off pcie_aspm.policy=performance". > 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); > -- > 2.47.1 > ^ permalink raw reply [flat|nested] 3+ messages in thread
* Re: [PATCH net 3/3] igc: return early when failing to read EECD register 2025-04-18 19:34 ` [PATCH net 3/3] igc: return early when failing to read EECD register Bjorn Helgaas @ 2025-04-22 17:16 ` Tony Nguyen [not found] ` <CAMqyJG1nm2mYnsXeF=h_xM_0ydAVFK9gdEznJO8hwd-B_2sm_w@mail.gmail.com> 0 siblings, 1 reply; 3+ messages in thread From: Tony Nguyen @ 2025-04-22 17:16 UTC (permalink / raw) To: Bjorn Helgaas Cc: davem, kuba, pabeni, edumazet, andrew+netdev, netdev, En-Wei Wu, vitaly.lifshits, dima.ruinskiy, Chia-Lin Kao (AceLan), Mor Bar-Gabay, Kalesh AP, Przemek Kitszel, linux-pci On 4/18/2025 12:34 PM, Bjorn Helgaas wrote: > [+cc Kalesh, Przemek, linux-pci] > > On Tue, Jan 07, 2025 at 11:01:47AM -0800, Tony Nguyen wrote: >> From: En-Wei Wu <en-wei.wu@canonical.com> >> >> 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> >> --- >> 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; > > I don't understand this. It looks like a band-aid that makes boot > faster but doesn't solve the real problem. > > In its defense, I guess that with this patch, the first igc probe > fails, and then for some reason we attempt another a few seconds > later, and the second igc probe works fine, so the NIC actually does > end up working correct, right? > > I think the PCI core has some issues with configuring ASPM L1.2, and I > wonder if those are relevant here. If somebody can repro the problem > (i.e., without this patch, which looks like it appeared in v6.13 as > bd2776e39c2a ("igc: return early when failing to read EECD > register")), I wonder if you could try booting with "pcie_port_pm=off > pcie_aspm.policy=performance" and see if that also avoids the problem? > > If so, I'd like to see the dmesg log with "pci=earlydump" and the > "sudo lspci -vv" output when booted with and without "pcie_port_pm=off > pcie_aspm.policy=performance". We weren't able to get a repro here. En-Wei would you be able to provide this to Bjorn? Thanks, Tony >> 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); >> -- >> 2.47.1 >> ^ permalink raw reply [flat|nested] 3+ messages in thread
[parent not found: <CAMqyJG1nm2mYnsXeF=h_xM_0ydAVFK9gdEznJO8hwd-B_2sm_w@mail.gmail.com>]
* Re: [PATCH net 3/3] igc: return early when failing to read EECD register [not found] ` <CAMqyJG1nm2mYnsXeF=h_xM_0ydAVFK9gdEznJO8hwd-B_2sm_w@mail.gmail.com> @ 2025-04-23 9:12 ` En-Wei WU 0 siblings, 0 replies; 3+ messages in thread From: En-Wei WU @ 2025-04-23 9:12 UTC (permalink / raw) To: Tony Nguyen Cc: Bjorn Helgaas, davem, kuba, pabeni, edumazet, andrew+netdev, netdev, vitaly.lifshits, dima.ruinskiy, Chia-Lin Kao (AceLan), Mor Bar-Gabay, Kalesh AP, Przemek Kitszel, linux-pci Sure, I'll access the machine and do the debugging next week. Thanks, En-Wei. On Wed, 23 Apr 2025 at 17:10, En-Wei WU <en-wei.wu@canonical.com> wrote: > > Sure, I'll access the machine and do the debugging next week. > > Thanks, > En-Wei. > > On Wed, 23 Apr 2025 at 01:16, Tony Nguyen <anthony.l.nguyen@intel.com> wrote: >> >> >> >> On 4/18/2025 12:34 PM, Bjorn Helgaas wrote: >> > [+cc Kalesh, Przemek, linux-pci] >> > >> > On Tue, Jan 07, 2025 at 11:01:47AM -0800, Tony Nguyen wrote: >> >> From: En-Wei Wu <en-wei.wu@canonical.com> >> >> >> >> 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> >> >> --- >> >> 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; >> > >> > I don't understand this. It looks like a band-aid that makes boot >> > faster but doesn't solve the real problem. >> > >> > In its defense, I guess that with this patch, the first igc probe >> > fails, and then for some reason we attempt another a few seconds >> > later, and the second igc probe works fine, so the NIC actually does >> > end up working correct, right? >> > >> > I think the PCI core has some issues with configuring ASPM L1.2, and I >> > wonder if those are relevant here. If somebody can repro the problem >> > (i.e., without this patch, which looks like it appeared in v6.13 as >> > bd2776e39c2a ("igc: return early when failing to read EECD >> > register")), I wonder if you could try booting with "pcie_port_pm=off >> > pcie_aspm.policy=performance" and see if that also avoids the problem? >> > >> > If so, I'd like to see the dmesg log with "pci=earlydump" and the >> > "sudo lspci -vv" output when booted with and without "pcie_port_pm=off >> > pcie_aspm.policy=performance". >> >> We weren't able to get a repro here. >> >> En-Wei would you be able to provide this to Bjorn? >> >> Thanks, >> Tony >> >> >> 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); >> >> -- >> >> 2.47.1 >> >> >> ^ permalink raw reply [flat|nested] 3+ messages in thread
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[not found] <20250107190150.1758577-4-anthony.l.nguyen@intel.com>
2025-04-18 19:34 ` [PATCH net 3/3] igc: return early when failing to read EECD register Bjorn Helgaas
2025-04-22 17:16 ` Tony Nguyen
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