linux/drivers/pci
Dexuan Cui f2c33ccacb PCI/PM: Always return devices to D0 when thawing
pci_pm_thaw_noirq() is supposed to return the device to D0 and restore its
configuration registers, but previously it only did that for devices whose
drivers implemented the new power management ops.

Hibernation, e.g., via "echo disk > /sys/power/state", involves freezing
devices, creating a hibernation image, thawing devices, writing the image,
and powering off.  The fact that thawing did not return devices with legacy
power management to D0 caused errors, e.g., in this path:

  pci_pm_thaw_noirq
    if (pci_has_legacy_pm_support(pci_dev)) # true for Mellanox VF driver
      return pci_legacy_resume_early(dev)   # ... legacy PM skips the rest
    pci_set_power_state(pci_dev, PCI_D0)
    pci_restore_state(pci_dev)
  pci_pm_thaw
    if (pci_has_legacy_pm_support(pci_dev))
      pci_legacy_resume
	drv->resume
	  mlx4_resume
	    ...
	      pci_enable_msix_range
	        ...
		  if (dev->current_state != PCI_D0)  # <---
		    return -EINVAL;

which caused these warnings:

  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

Return devices to D0 and restore config registers for all devices, not just
those whose drivers support new power management.

[bhelgaas: also call pci_restore_state() before pci_legacy_resume_early(),
update comment, add stable tag, commit log]
Link: https://lore.kernel.org/r/KU1P153MB016637CAEAD346F0AA8E3801BFAD0@KU1P153MB0166.APCP153.PROD.OUTLOOK.COM
Signed-off-by: Dexuan Cui <decui@microsoft.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Cc: stable@vger.kernel.org	# v4.13+
2019-11-20 17:32:25 -06:00
..
controller pci-v5.4-changes 2019-09-23 19:16:01 -07:00
endpoint PCI: endpoint: Clear BAR before freeing its space 2019-06-11 10:57:54 +01:00
hotplug pci-v5.4-changes 2019-09-23 19:16:01 -07:00
pcie pci-v5.4-changes 2019-09-23 19:16:01 -07:00
switch New feature to add support for NTB virtual MSI interrupts, the ability 2019-07-21 09:46:59 -07:00
access.c PCI: Make pcie_downstream_port() available outside of access.c 2019-09-07 07:45:25 -05:00
ats.c PCI: Fix typos and whitespace errors 2019-07-09 07:24:53 -05:00
bus.c PCI: Unexport pci_bus_get() and pci_bus_put() 2019-07-23 18:32:49 -05:00
ecam.c
host-bridge.c
iov.c Merge branch 'pci/resource' 2019-09-23 16:10:15 -05:00
irq.c
Kconfig pci-v5.4-changes 2019-09-23 19:16:01 -07:00
Makefile PCI: OF: Allow of_pci_get_max_link_speed() to be used by PCI Endpoint drivers 2019-04-15 13:24:02 +01:00
mmap.c PCI: Fix typos and whitespace errors 2019-07-09 07:24:53 -05:00
msi.c New feature to add support for NTB virtual MSI interrupts, the ability 2019-07-21 09:46:59 -07:00
of.c PCI: OF: Correct of_irq_parse_pci() documentation 2019-08-30 14:00:34 -05:00
p2pdma.c PCI/P2PDMA: Update pci_p2pdma_distance_many() documentation 2019-08-16 08:41:59 -05:00
pci-acpi.c Merge branch 'pci/enumeration' 2019-09-23 16:10:08 -05:00
pci-bridge-emul.c PCI: Use static const struct, not const static struct 2019-09-05 13:26:46 -05:00
pci-bridge-emul.h PCI: pci-bridge-emul: Extend pci_bridge_emul_init() with flags 2019-02-22 10:51:14 +00:00
pci-driver.c PCI/PM: Always return devices to D0 when thawing 2019-11-20 17:32:25 -06:00
pci-label.c
pci-mid.c
pci-pf-stub.c PCI: Fix typos and whitespace errors 2019-07-09 07:24:53 -05:00
pci-stub.c PCI: Replace printk(KERN_INFO) with pr_info(), etc 2019-05-09 07:49:54 -05:00
pci-sysfs.c Merge branch 'next-lockdown' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security 2019-09-28 08:14:15 -07:00
pci.c PCI: PM: Fix pci_power_up() 2019-10-15 23:51:36 +02:00
pci.h pci-v5.4-changes 2019-09-23 19:16:01 -07:00
probe.c pci-v5.4-changes 2019-09-23 19:16:01 -07:00
proc.c Merge branch 'next-lockdown' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security 2019-09-28 08:14:15 -07:00
quirks.c pci-v5.4-changes 2019-09-23 19:16:01 -07:00
remove.c
rom.c
search.c PCI: Unexport pci_bus_sem 2019-07-23 18:32:50 -05:00
setup-bus.c PCI: Use PCI_SRIOV_NUM_BARS in loops instead of PCI_IOV_RESOURCE_END 2019-08-08 15:12:12 -05:00
setup-irq.c
setup-res.c
slot.c PCI: Decode PCIe 32 GT/s link speed 2019-06-13 16:49:45 -05:00
syscall.c PCI: Lock down BAR access when the kernel is locked down 2019-08-19 21:54:15 -07:00
vc.c Merge branch 'pci/trivial' 2019-09-23 16:10:31 -05:00
vpd.c PCI/VPD: Prevent VPD access for Amazon's Annapurna Labs Root Port 2019-09-16 14:10:09 +01:00
xen-pcifront.c Merge branch 'pci/printk' 2019-05-13 18:34:46 -05:00