6.6-stable review patch. If anyone has any objections, please let me know.
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From: Mario Limonciello mario.limonciello@amd.com
[ Upstream commit 299fad4133677b845ce962f78c9cf75bded63f61 ]
When a device is surprise-removed (e.g., due to a dock unplug), the PCI core unconfigures all downstream devices and sets their error state to pci_channel_io_perm_failure. This marks them as disconnected via pci_dev_is_disconnected().
During device removal, the runtime PM framework may attempt to resume the device to D0 via pm_runtime_get_sync(), which calls into pci_power_up(). Since the device is already disconnected, this resume attempt is unnecessary and results in a predictable errors like this, typically when undocking from a TBT3 or USB4 dock with PCIe tunneling:
pci 0000:01:00.0: Unable to change power state from D3cold to D0, device inaccessible
Avoid powering up disconnected devices by checking their status early in pci_power_up() and returning -EIO.
Suggested-by: Lukas Wunner lukas@wunner.de Signed-off-by: Mario Limonciello mario.limonciello@amd.com [bhelgaas: add typical message] Signed-off-by: Bjorn Helgaas bhelgaas@google.com Reviewed-by: Lukas Wunner lukas@wunner.de Reviewed-by: Ilpo Järvinen ilpo.jarvinen@linux.intel.com Acked-by: Rafael J. Wysocki rafael@kernel.org Link: https://patch.msgid.link/20250909031916.4143121-1-superm1@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/pci/pci.c | 5 +++++ 1 file changed, 5 insertions(+)
diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c index df7f7e2ed0064..9a3f6bb60eb4d 100644 --- a/drivers/pci/pci.c +++ b/drivers/pci/pci.c @@ -1257,6 +1257,11 @@ int pci_power_up(struct pci_dev *dev) return -EIO; }
+ if (pci_dev_is_disconnected(dev)) { + dev->current_state = PCI_D3cold; + return -EIO; + } + pci_read_config_word(dev, dev->pm_cap + PCI_PM_CTRL, &pmcsr); if (PCI_POSSIBLE_ERROR(pmcsr)) { pci_err(dev, "Unable to change power state from %s to D0, device inaccessible\n",