6ab2e14ba7
commit f2c33ccacb2d4bbeae2a255a7ca0cbfd03017b7c upstream.
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+
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Linux kernel ============ This file was moved to Documentation/admin-guide/README.rst Please notice that there are several guides for kernel developers and users. These guides can be rendered in a number of formats, like HTML and PDF. In order to build the documentation, use ``make htmldocs`` or ``make pdfdocs``. There are various text files in the Documentation/ subdirectory, several of them using the Restructured Text markup notation. See Documentation/00-INDEX for a list of what is contained in each file. Please read the Documentation/process/changes.rst file, as it contains the requirements for building and running the kernel, and information about the problems which may result by upgrading your kernel.