A variety of issues both in function and in power consumption have been raised as a result of devices not being put into a low power state when the system is powered off.
There have been some localized changes[1] to PCI core to help these issues, but they have had various downsides. This series instead uses the driver hibernate flows when the system is being powered off or halted. This lines up the behavior with what other operating systems do as well. If for some reason that fails or is not supported, run driver shutdown() callbacks. Rafael did mention in earlier versions of the series concerns about regression risk. He was looking for thoughts from Greg who isn't against it but also isn't sure about how to maintain it. [1] This has been validated by me and several others in AMD on a variety of AMD hardware platforms. It's been validated by some community members on their Intel hardware. To my knowledge it has not been validated on non-x86. On my development laptop I have also contrived failures in the hibernation callbacks to make sure that the fallback to shutdown callback works. In order to assist with potential regressions the series also includes documentation to help with getting a kernel log at shutdown after the disk is unmounted. Cc: AceLan Kao <acelan....@canonical.com> Cc: Kai-Heng Feng <kaihe...@nvidia.com> Cc: Mark Pearson <mpearson-len...@squebb.ca> Cc: Merthan Karakaş <m3rth...@gmail.com> Cc: Eric Naim <dn...@cachyos.org> Link: https://lore.kernel.org/linux-usb/2025090852-coma-tycoon-9f37@gregkh/ [1] --- v6->v7: * Add documentation on how to debug a shutdown hang * Adjust commit messages per feedback from Bjorn Mario Limonciello (AMD) (12): PM: Introduce new PMSG_POWEROFF event scsi: Add PM_EVENT_POWEROFF into suspend callbacks usb: sl811-hcd: Add PM_EVENT_POWEROFF into suspend callbacks USB: Pass PMSG_POWEROFF event to suspend_common() PCI/PM: Disable device wakeups when halting or powering off system PCI/PM: Split out code from pci_pm_suspend_noirq() into helper PCI/PM: Run bridge power up actions as part of restore phase PCI/PM: Use pci_power_manageable() in pci_pm_poweroff_noirq() PCI: Put PCIe bridges with downstream devices into D3 at hibernate drm/amd: Avoid evicting resources at S5 PM: Use hibernate flows for system power off Documentation: power: Add document on debugging shutdown hangs Documentation/power/index.rst | 1 + Documentation/power/shutdown-debugging.rst | 55 ++++++++++++ drivers/base/power/main.c | 7 ++ drivers/gpu/drm/amd/amdgpu/amdgpu_device.c | 4 + drivers/pci/pci-driver.c | 99 +++++++++++++++------- drivers/scsi/mesh.c | 1 + drivers/scsi/stex.c | 1 + drivers/usb/core/hcd-pci.c | 11 ++- drivers/usb/host/sl811-hcd.c | 1 + include/linux/pm.h | 5 +- include/trace/events/power.h | 3 +- kernel/reboot.c | 6 ++ 12 files changed, 159 insertions(+), 35 deletions(-) create mode 100644 Documentation/power/shutdown-debugging.rst base-commit: 76eeb9b8de9880ca38696b2fb56ac45ac0a25c6c -- 2.43.0
