Commit 0a6ad4d9 authored Aug 06, 2024 by Vitaly Lifshits Committed by Tony Nguyen Aug 30, 2024

e1000e: avoid failing the system during pm_suspend

Occasionally when the system goes into pm_suspend, the suspend might fail
due to a PHY access error on the network adapter. Previously, this would
have caused the whole system to fail to go to a low power state.
An example of this was reported in the following Bugzilla:
https://bugzilla.kernel.org/show_bug.cgi?id=205015

[ 1663.694828] e1000e 0000:00:19.0 eth0: Failed to disable ULP
[ 1664.731040] asix 2-3:1.0 eth1: link up, 100Mbps, full-duplex, lpa 0xC1E1
[ 1665.093513] e1000e 0000:00:19.0 eth0: Hardware Error
[ 1665.596760] e1000e 0000:00:19.0: pci_pm_resume+0x0/0x80 returned 0 after 2975399 usecs

and then the system never recovers from it, and all the following suspend failed due to this
[22909.393854] PM: pci_pm_suspend(): e1000e_pm_suspend+0x0/0x760 [e1000e] returns -2
[22909.393858] PM: dpm_run_callback(): pci_pm_suspend+0x0/0x160 returns -2
[22909.393861] PM: Device 0000:00:1f.6 failed to suspend async: error -2

This can be avoided by changing the return values of __e1000_shutdown and
e1000e_pm_suspend functions so that they always return 0 (success). This
is consistent with what other drivers do.

If the e1000e driver encounters a hardware error during suspend, potential
side effects include slightly higher power draw or non-working wake on
LAN. This is preferred to a system-level suspend failure, and a warning
message is written to the system log, so that the user can be aware that
the LAN controller experienced a problem during suspend.

Link: https://bugzilla.kernel.org/show_bug.cgi?id=205015


Suggested-by: Dima Ruinskiy <dima.ruinskiy@intel.com>
Signed-off-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>

parent f9cb5e01

drivers/net/ethernet/intel/e1000e/netdev.c

+11 −8

Original line number	Diff line number	Diff line
		@@ -6671,8 +6671,10 @@ static int __e1000_shutdown(struct pci_dev *pdev, bool runtime)
		if (adapter->flags2 & FLAG2_HAS_PHY_WAKEUP) {
		/* enable wakeup by the PHY */
		retval = e1000_init_phy_wakeup(adapter, wufc);
		if (retval)
		return retval;
		if (retval) {
		e_err("Failed to enable wakeup\n");
		goto skip_phy_configurations;
		}
		} else {
		/* enable wakeup by the MAC */
		ew32(WUFC, wufc);
		@@ -6693,8 +6695,10 @@ static int __e1000_shutdown(struct pci_dev *pdev, bool runtime)
		* or broadcast.
		*/
		retval = e1000_enable_ulp_lpt_lp(hw, !runtime);
		if (retval)
		return retval;
		if (retval) {
		e_err("Failed to enable ULP\n");
		goto skip_phy_configurations;
		}
		}
		}

		@@ -6726,6 +6730,7 @@ static int __e1000_shutdown(struct pci_dev *pdev, bool runtime)
		hw->phy.ops.release(hw);
		}

		skip_phy_configurations:
		/* Release control of h/w to f/w. If f/w is AMT enabled, this
		* would have already happened in close and is redundant.
		*/
		@@ -6968,15 +6973,13 @@ static int e1000e_pm_suspend(struct device *dev)
		e1000e_pm_freeze(dev);

		rc = __e1000_shutdown(pdev, false);
		if (rc) {
		e1000e_pm_thaw(dev);
		} else {
		if (!rc) {
		/* Introduce S0ix implementation */
		if (adapter->flags2 & FLAG2_ENABLE_S0IX_FLOWS)
		e1000e_s0ix_entry_flow(adapter);
		}

		return rc;
		return 0;
		}

		static int e1000e_pm_resume(struct device *dev)