** Description changed: + [SRU Justification] + + Impact: Reported regression to PCI pass-through in QEMU/KVM + (https://lists.ubuntu.com/archives/kernel-team/2025-July/161565.html) + which was caused by changes to fix suspend/resume on disks with BIOS + password set (bug #2110090). + + Fix: Upstream fix from 6.16-rc3 addressing the issue (see below) + + Testcase: Requires to set up a VM with PCI pass-through. + + Regression potential: Things related to PCI power management (devices + not being initialized or not properly resuming after suspend). + + --- original description --- + From: Thomas Lamprecht <t.lampre...@proxmox.com> Subject: Re: [PATCH 1/1][SRU][N] PCI: Explicitly put devices into D0 when initializing ... FYI: This causes regressions on PCI passthrough to QEMU/KVM, among other things. A colleague found that the following patch on top fixes it here: commit 907a7a2e5bf40c6a359b2f6cc53d6fdca04009e0 Author: Mario Limonciello <mario.limoncie...@amd.com> Date: Wed Jun 11 18:31:16 2025 -0500 - PCI/PM: Set up runtime PM even for devices without PCI PM - - 4d4c10f763d7 ("PCI: Explicitly put devices into D0 when initializing") - intended to put PCI devices into D0, but in doing so unintentionally - changed runtime PM initialization not to occur on devices that don't - support PCI PM. This caused a regression in vfio-pci due to an imbalance - with its use. - - Adjust the logic in pci_pm_init() so that even if PCI PM isn't supported - runtime PM is still initialized. - - Fixes: 4d4c10f763d7 ("PCI: Explicitly put devices into D0 when initializing") - Reported-by: Giovanni Cabiddu <giovanni.cabi...@intel.com> - Closes: https://lore.kernel.org/linux-pci/20250424043232.1848107-1-supe...@kernel.org/T/#m7e8929d6421690dc8bd6dc639d86c2b4db27cbc4 - Reported-by: Nicolas Dichtel <nicolas.dich...@6wind.com> - Closes: https://lore.kernel.org/linux-pci/20250424043232.1848107-1-supe...@kernel.org/T/#m40d277dcdb9be64a1609a82412d1aa906263e201 - Signed-off-by: Mario Limonciello <mario.limoncie...@amd.com> - Signed-off-by: Bjorn Helgaas <bhelg...@google.com> - Tested-by: Giovanni Cabiddu <giovanni.cabi...@intel.com> - Tested-by: Nicolas Dichtel <nicolas.dich...@6wind.com> - Reviewed-by: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppusw...@linux.intel.com> - Acked-by: Rafael J. Wysocki <raf...@kernel.org> - Cc: Alex Williamson <alex.william...@redhat.com> - Link: https://patch.msgid.link/20250611233117.61810-1-supe...@kernel.org + PCI/PM: Set up runtime PM even for devices without PCI PM + + 4d4c10f763d7 ("PCI: Explicitly put devices into D0 when initializing") + intended to put PCI devices into D0, but in doing so unintentionally + changed runtime PM initialization not to occur on devices that don't + support PCI PM. This caused a regression in vfio-pci due to an imbalance + with its use. + + Adjust the logic in pci_pm_init() so that even if PCI PM isn't supported + runtime PM is still initialized. + + Fixes: 4d4c10f763d7 ("PCI: Explicitly put devices into D0 when initializing") + Reported-by: Giovanni Cabiddu <giovanni.cabi...@intel.com> + Closes: https://lore.kernel.org/linux-pci/20250424043232.1848107-1-supe...@kernel.org/T/#m7e8929d6421690dc8bd6dc639d86c2b4db27cbc4 + Reported-by: Nicolas Dichtel <nicolas.dich...@6wind.com> + Closes: https://lore.kernel.org/linux-pci/20250424043232.1848107-1-supe...@kernel.org/T/#m40d277dcdb9be64a1609a82412d1aa906263e201 + Signed-off-by: Mario Limonciello <mario.limoncie...@amd.com> + Signed-off-by: Bjorn Helgaas <bhelg...@google.com> + Tested-by: Giovanni Cabiddu <giovanni.cabi...@intel.com> + Tested-by: Nicolas Dichtel <nicolas.dich...@6wind.com> + Reviewed-by: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppusw...@linux.intel.com> + Acked-by: Rafael J. Wysocki <raf...@kernel.org> + Cc: Alex Williamson <alex.william...@redhat.com> + Link: https://patch.msgid.link/20250611233117.61810-1-supe...@kernel.org Same holds for the Plucky backport in patch mail id: <20250529010730.1863186-2-acelan....@canonical.com>
-- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/2117494 Title: [Regression Updates] "PCI: Explicitly put devices into D0 when initializing" breaks pci-pass-through in QEMU/KVM To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/2117494/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
