kernel/linux.git/drivers/pci/remove.c, branch v6.18.21

Merge branch 'pci/virtualization'

2025-10-03T17:13:12+00:00

- Add rescan/remove locking when enabling/disabling SR-IOV, which solves list corruption on s390, where disabling SR-IOV also generates hotplug events (Niklas Schnelle) - Add lockdep assertion in pci_stop_and_remove_bus_device() to catch device removal without appropriate locking (Niklas Schnelle) * pci/virtualization: PCI: Add lockdep assertion in pci_stop_and_remove_bus_device() PCI/IOV: Add PCI rescan-remove locking when enabling/disabling SR-IOV

PCI: Add lockdep assertion in pci_stop_and_remove_bus_device()

2025-09-26T21:01:17+00:00

Removing a PCI devices requires holding pci_rescan_remove_lock. Prompted by this being missed in sriov_disable() and going unnoticed since its inception, add a lockdep assert so this doesn't get missed again in the future. Signed-off-by: Niklas Schnelle Signed-off-by: Bjorn Helgaas Reviewed-by: Benjamin Block Reviewed-by: Julian Ruess Link: https://patch.msgid.link/20250826-pci_fix_sriov_disable-v1-2-2d0bc938f2a3@linux.ibm.com

PCI/pwrctrl: Fix device leak at device stop

2025-08-27T19:32:25+00:00

Make sure to drop the reference to the pwrctrl device taken by of_find_device_by_node() when stopping a PCI device. Fixes: 681725afb6b9 ("PCI/pwrctl: Remove pwrctl device without iterating over all children of pwrctl parent") Signed-off-by: Johan Hovold Signed-off-by: Bjorn Helgaas Reviewed-by: Manivannan Sadhasivam Cc: stable@vger.kernel.org # v6.13 Link: https://patch.msgid.link/20250721153609.8611-4-johan+linaro@kernel.org

Merge branch 'pci/devtree-create'

2025-03-27T18:14:45+00:00

- Add device_add_of_node() to set dev->of_node and dev->fwnode only if they haven't been set already (Herve Codina) - Allow of_pci_set_address() to set the DT address property for root bus nodes, where there is no PCI bridge to supply the PCI bus/device/function part of the property (Herve Codina) - Create DT nodes for PCI host bridges to enable loading device tree overlays to create platform devices for PCI devices that have several features that require multiple drivers (Herve Codina) * pci/devtree-create: PCI: of: Create device tree PCI host bridge node PCI: of_property: Constify parameter in of_pci_get_addr_flags() PCI: of_property: Add support for NULL pdev in of_pci_set_address() PCI: of: Use device_{add,remove}_of_node() to attach of_node to existing device driver core: Introduce device_{add,remove}_of_node()

Merge branch 'pci/pwrctrl'

2025-03-27T18:14:44+00:00

- Create pwrctrl devices in pci_scan_device() to make it more symmetric with pci_pwrctrl_unregister() and make pwrctrl devices for PCI bridges possible (Manivannan Sadhasivam) - Unregister pwrctrl devices in pci_destroy_dev() so DOE, ASPM, etc. can still access devices after pci_stop_dev() (Manivannan Sadhasivam) - If there's a pwrctrl device for a PCI device, skip scanning it because the pwrctrl core will rescan the bus after the device is powered on (Manivannan Sadhasivam) - Add a pwrctrl driver for PCI slots based on voltage regulators described via devicetree (Manivannan Sadhasivam) * pci/pwrctrl: PCI/pwrctrl: Add pwrctrl driver for PCI slots dt-bindings: vendor-prefixes: Document the 'pciclass' prefix PCI/pwrctrl: Skip scanning for the device further if pwrctrl device is created PCI/pwrctrl: Move pci_pwrctrl_unregister() to pci_destroy_dev() PCI/pwrctrl: Move creation of pwrctrl devices to pci_scan_device()

PCI/DOE: Expose DOE features via sysfs

2025-03-21T21:36:01+00:00

PCIe r6.0 added support for Data Object Exchange (DOE). When DOE is supported, the DOE Discovery Feature must be implemented per PCIe r6.1, sec 6.30.1.1. DOE allows a requester to obtain information about the other DOE features supported by the device. The kernel already queries the DOE features supported and caches the values. Expose the values in sysfs to allow user space to determine which DOE features are supported by the PCIe device. By exposing the information to userspace, tools like lspci can relay the information to users. By listing all of the supported features we can allow userspace to parse the list, which might include vendor specific features as well as yet to be supported features. As the DOE Discovery feature must always be supported we treat it as a special named attribute case. This allows the usual PCI attribute_group handling to correctly create the doe_features directory when registering pci_doe_sysfs_group (otherwise it doesn't and sysfs_add_file_to_group() will seg fault). After this patch is supported you can see something like this when attaching a DOE device: $ ls /sys/devices/pci0000:00/0000:00:02.0//doe* 0001:01 0001:02 doe_discovery Link: https://lore.kernel.org/r/20250306075211.1855177-3-alistair@alistair23.me Signed-off-by: Alistair Francis [bhelgaas: drop pci_doe_sysfs_init() stub return, make DEVICE_ATTR_RO(doe_discovery) static] Signed-off-by: Bjorn Helgaas Reviewed-by: Jonathan Cameron

PCI: of: Create device tree PCI host bridge node

2025-02-28T21:13:51+00:00

PCI devices device tree nodes can be already created. This was introduced by commit 407d1a51921e ("PCI: Create device tree node for bridge"). In order to have device tree nodes related to PCI devices attached on their PCI root bus (the PCI bus handled by the PCI host bridge), a PCI root bus device tree node is needed. This root bus node will be used as the parent node of the first level devices scanned on the bus. On device tree based systems, this PCI root bus device tree node is set to the node of the related PCI host bridge. The PCI host bridge node is available in the device tree used to describe the hardware passed at boot. On non device tree based system (such as ACPI), a device tree node for the PCI host bridge or for the root bus does not exist. Indeed, the PCI host bridge is not described in a device tree used at boot simply because no device tree is passed at boot. The device tree PCI host bridge node creation needs to be done at runtime. This is done in the same way as for the creation of the PCI device nodes. I.e. node and properties are created based on computed information done by the PCI core. Also, as is done on device tree based systems, this PCI host bridge node is used for the PCI root bus. With this done, hardware available in a PCI device that doesn't follow the PCI model consisting in one PCI function handled by one driver can be described by a device tree overlay loaded by the PCI device driver on non device tree based systems. Those PCI devices provide a single PCI function that includes several functionalities that require different drivers. The device tree overlay describes the internal devices and their relationships. It allows to load drivers needed by those different devices in order to have functionalities handled. Link: https://lore.kernel.org/r/20250224141356.36325-6-herve.codina@bootlin.com Signed-off-by: Herve Codina Signed-off-by: Bjorn Helgaas Reviewed-by: Rob Herring (Arm)

PCI/pwrctrl: Move pci_pwrctrl_unregister() to pci_destroy_dev()

2025-02-20T10:59:10+00:00

The PCI core will try to access the devices even after pci_stop_dev() for things like Data Object Exchange (DOE), ASPM, etc. So, move pci_pwrctrl_unregister() to the near end of pci_destroy_dev() to make sure that the devices are powered down only after the PCI core is done with them. Suggested-by: Lukas Wunner Reviewed-by: Lukas Wunner Tested-by: Bartosz Golaszewski Signed-off-by: Manivannan Sadhasivam Link: https://lore.kernel.org/r/20250116-pci-pwrctrl-slot-v3-2-827473c8fbf4@linaro.org [kwilczynski: commit log] Signed-off-by: Krzysztof Wilczyński

PCI/pwrctrl: Unregister platform device only if one actually exists

2024-11-30T17:41:25+00:00

If a PCI device has an associated device_node with power supplies, pci_bus_add_device() creates platform devices for use by pwrctrl. When the PCI device is removed, pci_stop_dev() uses of_find_device_by_node() to locate the related platform device, then unregisters it. But when we remove a PCI device with no associated device node, dev_of_node(dev) is NULL, and of_find_device_by_node(NULL) returns the first device with "dev->of_node == NULL". The result is that we (a) mistakenly unregister a completely unrelated platform device, leading to issues like the first trace below, and (b) dereference the NULL pointer from dev_of_node() when clearing OF_POPULATED, as in the second trace. Unregister a platform device only if there is one associated with this PCI device. This resolves issues seen when doing: # echo 1 > /sys/bus/pci/devices/.../remove Sample issue from unregistering the wrong platform device: WARNING: CPU: 0 PID: 5095 at drivers/regulator/core.c:5885 regulator_unregister+0x140/0x160 Call trace: regulator_unregister+0x140/0x160 devm_rdev_release+0x1c/0x30 release_nodes+0x68/0x100 devres_release_all+0x98/0xf8 device_unbind_cleanup+0x20/0x70 device_release_driver_internal+0x1f4/0x240 device_release_driver+0x20/0x40 bus_remove_device+0xd8/0x170 device_del+0x154/0x380 device_unregister+0x28/0x88 of_device_unregister+0x1c/0x30 pci_stop_bus_device+0x154/0x1b0 pci_stop_and_remove_bus_device_locked+0x28/0x48 remove_store+0xa0/0xb8 dev_attr_store+0x20/0x40 sysfs_kf_write+0x4c/0x68 Later NULL pointer dereference for of_node_clear_flag(NULL, OF_POPULATED): Unable to handle kernel NULL pointer dereference at virtual address 00000000000000c0 Call trace: pci_stop_bus_device+0x190/0x1b0 pci_stop_and_remove_bus_device_locked+0x28/0x48 remove_store+0xa0/0xb8 dev_attr_store+0x20/0x40 sysfs_kf_write+0x4c/0x68 Link: https://lore.kernel.org/r/20241126210443.4052876-1-briannorris@chromium.org Fixes: 681725afb6b9 ("PCI/pwrctl: Remove pwrctl device without iterating over all children of pwrctl parent") Reported-by: Saurabh Sengar Closes: https://lore.kernel.org/r/1732890621-19656-1-git-send-email-ssengar@linux.microsoft.com Signed-off-by: Brian Norris [bhelgaas: commit log] Signed-off-by: Bjorn Helgaas

Merge branch 'pci/pwrctl'

2024-11-25T19:40:54+00:00

- Use of_platform_device_create() instead of of_platform_populate() to create pwrctl platform devices so we can control it based on the child nodes (Manivannan Sadhasivam) - Create pwrctrl platform devices only if there's a relevant power supply property (Manivannan Sadhasivam) - Add device link from the pwrctl supplier to the PCI dev to ensure pwrctl drivers are probed before the PCI dev driver; this avoids a race where pwrctl could change device power state while the PCI driver was active (Manivannan Sadhasivam) - Find pwrctl device for removal with of_find_device_by_node() instead of searching all children of the parent (Manivannan Sadhasivam) - Rename 'pwrctl' to 'pwrctrl' to use the same 'ctrl' suffix as 'bwctrl' and other PCI files to reduce confusion (Bjorn Helgaas) * pci/pwrctl: PCI/pwrctrl: Rename pwrctrl functions and structures PCI/pwrctrl: Rename pwrctl files to pwrctrl PCI/pwrctl: Remove pwrctl device without iterating over all children of pwrctl parent PCI/pwrctl: Ensure that pwrctl drivers are probed before PCI client drivers PCI/pwrctl: Create pwrctl device only if at least one power supply is present PCI/pwrctl: Use of_platform_device_create() to create pwrctl devices # Conflicts: # drivers/pci/bus.c # drivers/pci/remove.c