In pci_legacy_suspend_late(), the device state is moved to PCI_UNKNOWN. In pci_pm_thaw_noirq(), the state is supposed to be moved back to PCI_D0, but the current code misses the pci_legacy_resume_early() path, so the state remains in PCI_UNKNOWN in that path, and during hiberantion this causes an error for the Mellanox VF driver, which fails to enable MSI-X: pci_msi_supported() is false due to dev->current_state != PCI_D0: mlx4_core a6d1:00:02.0: Detected virtual function - running in slave mode mlx4_core a6d1:00:02.0: Sending reset mlx4_core a6d1:00:02.0: Sending vhcr0 mlx4_core a6d1:00:02.0: HCA minimum page size:512 mlx4_core a6d1:00:02.0: Timestamping is not supported in slave mode mlx4_core a6d1:00:02.0: INTx is not supported in multi-function mode, aborting PM: dpm_run_callback(): pci_pm_thaw+0x0/0xd7 returns -95 PM: Device a6d1:00:02.0 failed to thaw: error -95 Signed-off-by: Dexuan Cui <decui@xxxxxxxxxxxxx> --- drivers/pci/pci-driver.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) diff --git a/drivers/pci/pci-driver.c b/drivers/pci/pci-driver.c index 36dbe960306b..27dfc68db9e7 100644 --- a/drivers/pci/pci-driver.c +++ b/drivers/pci/pci-driver.c @@ -1074,15 +1074,16 @@ static int pci_pm_thaw_noirq(struct device *dev) return error; } - if (pci_has_legacy_pm_support(pci_dev)) - return pci_legacy_resume_early(dev); - /* * pci_restore_state() requires the device to be in D0 (because of MSI * restoration among other things), so force it into D0 in case the * driver's "freeze" callbacks put it into a low-power state directly. */ pci_set_power_state(pci_dev, PCI_D0); + + if (pci_has_legacy_pm_support(pci_dev)) + return pci_legacy_resume_early(dev); + pci_restore_state(pci_dev); if (drv && drv->pm && drv->pm->thaw_noirq) -- 2.19.1
