kernel/linux.git/drivers/pci/hotplug, branch v6.12.80

PCI: pnv_php: Fix surprise plug detection and recovery

2025-08-15T10:14:04+00:00

[ Upstream commit a2a2a6fc2469524caa713036297c542746d148dc ] The existing PowerNV hotplug code did not handle surprise plug events correctly, leading to a complete failure of the hotplug system after device removal and a required reboot to detect new devices. This comes down to two issues: 1) When a device is surprise removed, often the bridge upstream port will cause a PE freeze on the PHB. If this freeze is not cleared, the MSI interrupts from the bridge hotplug notification logic will not be received by the kernel, stalling all plug events on all slots associated with the PE. 2) When a device is removed from a slot, regardless of surprise or programmatic removal, the associated PHB/PE ls left frozen. If this freeze is not cleared via a fundamental reset, skiboot is unable to clear the freeze and cannot retrain / rescan the slot. This also requires a reboot to clear the freeze and redetect the device in the slot. Issue the appropriate unfreeze and rescan commands on hotplug events, and don't oops on hotplug if pci_bus_to_OF_node() returns NULL. Signed-off-by: Timothy Pearson [bhelgaas: tidy comments] Signed-off-by: Bjorn Helgaas Signed-off-by: Madhavan Srinivasan Link: https://patch.msgid.link/171044224.1359864.1752615546988.JavaMail.zimbra@raptorengineeringinc.com Signed-off-by: Sasha Levin

PCI: pnv_php: Work around switches with broken presence detection

2025-08-15T10:14:03+00:00

[ Upstream commit 80f9fc2362797538ebd4fd70a1dfa838cc2c2cdb ] The Microsemi Switchtec PM8533 PFX 48xG3 [11f8:8533] PCIe switch system was observed to incorrectly assert the Presence Detect Set bit in its capabilities when tested on a Raptor Computing Systems Blackbird system, resulting in the hot insert path never attempting a rescan of the bus and any downstream devices not being re-detected. Work around this by additionally checking whether the PCIe data link is active or not when performing presence detection on downstream switches' ports, similar to the pciehp_hpc.c driver. Signed-off-by: Shawn Anastasio Signed-off-by: Timothy Pearson Signed-off-by: Bjorn Helgaas Signed-off-by: Madhavan Srinivasan Link: https://patch.msgid.link/505981576.1359853.1752615415117.JavaMail.zimbra@raptorengineeringinc.com Signed-off-by: Sasha Levin

PCI: pnv_php: Clean up allocated IRQs on unplug

2025-08-15T10:14:03+00:00

[ Upstream commit 4668619092554e1b95c9a5ac2941ca47ba6d548a ] When the root of a nested PCIe bridge configuration is unplugged, the pnv_php driver leaked the allocated IRQ resources for the child bridges' hotplug event notifications, resulting in a panic. Fix this by walking all child buses and deallocating all its IRQ resources before calling pci_hp_remove_devices(). Also modify the lifetime of the workqueue at struct pnv_php_slot::wq so that it is only destroyed in pnv_php_free_slot(), instead of pnv_php_disable_irq(). This is required since pnv_php_disable_irq() will now be called by workers triggered by hot unplug interrupts, so the workqueue needs to stay allocated. The abridged kernel panic that occurs without this patch is as follows: WARNING: CPU: 0 PID: 687 at kernel/irq/msi.c:292 msi_device_data_release+0x6c/0x9c CPU: 0 UID: 0 PID: 687 Comm: bash Not tainted 6.14.0-rc5+ #2 Call Trace: msi_device_data_release+0x34/0x9c (unreliable) release_nodes+0x64/0x13c devres_release_all+0xc0/0x140 device_del+0x2d4/0x46c pci_destroy_dev+0x5c/0x194 pci_hp_remove_devices+0x90/0x128 pci_hp_remove_devices+0x44/0x128 pnv_php_disable_slot+0x54/0xd4 power_write_file+0xf8/0x18c pci_slot_attr_store+0x40/0x5c sysfs_kf_write+0x64/0x78 kernfs_fop_write_iter+0x1b0/0x290 vfs_write+0x3bc/0x50c ksys_write+0x84/0x140 system_call_exception+0x124/0x230 system_call_vectored_common+0x15c/0x2ec Signed-off-by: Shawn Anastasio Signed-off-by: Timothy Pearson [bhelgaas: tidy comments] Signed-off-by: Bjorn Helgaas Signed-off-by: Madhavan Srinivasan Link: https://patch.msgid.link/2013845045.1359852.1752615367790.JavaMail.zimbra@raptorengineeringinc.com Signed-off-by: Sasha Levin

s390/pci: Prevent self deletion in disable_slot()

2025-06-27T10:11:14+00:00

commit 47c397844869ad0e6738afb5879c7492f4691122 upstream. As disable_slot() takes a struct zpci_dev from the Configured to the Standby state. In Standby there is still a hotplug slot so this is not usually a case of sysfs self deletion. This is important because self deletion gets very hairy in terms of locking (see for example recover_store() in arch/s390/pci/pci_sysfs.c). Because the pci_dev_put() is not within the critical section of the zdev->state_lock however, disable_slot() can turn into a case of self deletion if zPCI device event handling slips between the mutex_unlock() and the pci_dev_put(). If the latter is the last put and zpci_release_device() is called this then tries to remove the hotplug slot via zpci_exit_slot() which will try to remove the hotplug slot directory the disable_slot() is part of i.e. self deletion. Prevent this by widening the zdev->state_lock critical section to include the pci_dev_put() which is then guaranteed to happen with the struct zpci_dev still in Standby state ensuring it will not lead to a zpci_release_device() call as at least the zPCI event handling code still holds a reference. Cc: stable@vger.kernel.org Fixes: a46044a92add ("s390/pci: fix zpci_zdev_put() on reserve") Reviewed-by: Gerd Bayer Tested-by: Gerd Bayer Signed-off-by: Niklas Schnelle Signed-off-by: Heiko Carstens Signed-off-by: Greg Kroah-Hartman

s390/pci: Fix duplicate pci_dev_put() in disable_slot() when PF has child VFs

2025-05-18T06:24:47+00:00

commit 05a2538f2b48500cf4e8a0a0ce76623cc5bafcf1 upstream. With commit bcb5d6c76903 ("s390/pci: introduce lock to synchronize state of zpci_dev's") the code to ignore power off of a PF that has child VFs was changed from a direct return to a goto to the unlock and pci_dev_put() section. The change however left the existing pci_dev_put() untouched resulting in a doubple put. This can subsequently cause a use after free if the struct pci_dev is released in an unexpected state. Fix this by removing the extra pci_dev_put(). Cc: stable@vger.kernel.org Fixes: bcb5d6c76903 ("s390/pci: introduce lock to synchronize state of zpci_dev's") Signed-off-by: Niklas Schnelle Reviewed-by: Gerd Bayer Signed-off-by: Heiko Carstens Signed-off-by: Greg Kroah-Hartman

PCI: pciehp: Avoid unnecessary device replacement check

2025-04-20T08:15:57+00:00

commit e3260237aaadc9799107ccb940c6688195c4518d upstream. Hot-removal of nested PCI hotplug ports suffers from a long-standing race condition which can lead to a deadlock: A parent hotplug port acquires pci_lock_rescan_remove(), then waits for pciehp to unbind from a child hotplug port. Meanwhile that child hotplug port tries to acquire pci_lock_rescan_remove() as well in order to remove its own children. The deadlock only occurs if the parent acquires pci_lock_rescan_remove() first, not if the child happens to acquire it first. Several workarounds to avoid the issue have been proposed and discarded over the years, e.g.: https://lore.kernel.org/r/4c882e25194ba8282b78fe963fec8faae7cf23eb.1529173804.git.lukas@wunner.de/ A proper fix is being worked on, but needs more time as it is nontrivial and necessarily intrusive. Recent commit 9d573d19547b ("PCI: pciehp: Detect device replacement during system sleep") provokes more frequent occurrence of the deadlock when removing more than one Thunderbolt device during system sleep. The commit sought to detect device replacement, but also triggered on device removal. Differentiating reliably between replacement and removal is impossible because pci_get_dsn() returns 0 both if the device was removed, as well as if it was replaced with one lacking a Device Serial Number. Avoid the more frequent occurrence of the deadlock by checking whether the hotplug port itself was hot-removed. If so, there's no sense in checking whether its child device was replaced. This works because the ->resume_noirq() callback is invoked in top-down order for the entire hierarchy: A parent hotplug port detecting device replacement (or removal) marks all children as removed using pci_dev_set_disconnected() and a child hotplug port can then reliably detect being removed. Link: https://lore.kernel.org/r/02f166e24c87d6cde4085865cce9adfdfd969688.1741674172.git.lukas@wunner.de Fixes: 9d573d19547b ("PCI: pciehp: Detect device replacement during system sleep") Reported-by: Kenneth Crudup Closes: https://lore.kernel.org/r/83d9302a-f743-43e4-9de2-2dd66d91ab5b@panix.com/ Reported-by: Chia-Lin Kao (AceLan) Closes: https://lore.kernel.org/r/20240926125909.2362244-1-acelan.kao@canonical.com/ Tested-by: Kenneth Crudup Tested-by: Mika Westerberg Signed-off-by: Lukas Wunner Signed-off-by: Bjorn Helgaas Reviewed-by: Mika Westerberg Reviewed-by: Kuppuswamy Sathyanarayanan Cc: stable@vger.kernel.org # v6.11+ Signed-off-by: Greg Kroah-Hartman

PCI: pciehp: Don't enable HPIE when resuming in poll mode

2025-04-10T12:39:16+00:00

[ Upstream commit 527664f738afb6f2c58022cd35e63801e5dc7aec ] PCIe hotplug can operate in poll mode without interrupt handlers using a polling kthread only. eb34da60edee ("PCI: pciehp: Disable hotplug interrupt during suspend") failed to consider that and enables HPIE (Hot-Plug Interrupt Enable) unconditionally when resuming the Port. Only set HPIE if non-poll mode is in use. This makes pcie_enable_interrupt() match how pcie_enable_notification() already handles HPIE. Link: https://lore.kernel.org/r/20250321162114.3939-1-ilpo.jarvinen@linux.intel.com Fixes: eb34da60edee ("PCI: pciehp: Disable hotplug interrupt during suspend") Signed-off-by: Ilpo Järvinen Signed-off-by: Bjorn Helgaas Reviewed-by: Lukas Wunner Signed-off-by: Sasha Levin

PCI: cpqphp: Fix PCIBIOS_* return value confusion

2024-12-05T13:02:21+00:00

[ Upstream commit e2226dbc4a4919d9c8bd9293299b532090bdf020 ] Code in and related to PCI_RefinedAccessConfig() has three types of return type confusion: - PCI_RefinedAccessConfig() tests pci_bus_read_config_dword() return value against -1. - PCI_RefinedAccessConfig() returns both -1 and PCIBIOS_* return codes. - Callers of PCI_RefinedAccessConfig() only test for -1. Make PCI_RefinedAccessConfig() return PCIBIOS_* codes consistently and adapt callers accordingly. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Link: https://lore.kernel.org/r/20241022091140.3504-2-ilpo.jarvinen@linux.intel.com Signed-off-by: Ilpo Järvinen Signed-off-by: Bjorn Helgaas Signed-off-by: Sasha Levin

Merge tag 'pci-v6.12-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/pci/pci

2024-09-23T19:47:06+00:00

Pull pci updates from Bjorn Helgaas: "Enumeration: - Wait for device readiness after reset by polling Vendor ID and looking for Configuration RRS instead of polling the Command register and looking for non-error completions, to avoid hardware retries done for RRS on non-Vendor ID reads (Bjorn Helgaas) - Rename CRS Completion Status to RRS ('Request Retry Status') to match PCIe r6.0 spec usage (Bjorn Helgaas) - Clear LBMS bit after a manual link retrain so we don't try to retrain a link when there's no downstream device anymore (Maciej W. Rozycki) - Revert to the original link speed after retraining fails instead of leaving it restricted to 2.5GT/s, so a future device has a chance to use higher speeds (Maciej W. Rozycki) - Wait for each level of downstream bus, not just the first, to become accessible before restoring devices on that bus (Ilpo Järvinen) - Add ARCH_PCI_DEV_GROUPS so s390 can add its own attribute_groups without having to stomp on the core's pdev->dev.groups (Lukas Wunner) Driver binding: - Export pcim_request_region(), a managed counterpart of pci_request_region(), for use by drivers (Philipp Stanner) - Export pcim_iomap_region() and deprecate pcim_iomap_regions() (Philipp Stanner) - Request the PCI BAR used by xboxvideo (Philipp Stanner) - Request and map drm/ast BARs with pcim_iomap_region() (Philipp Stanner) MSI: - Add MSI_FLAG_NO_AFFINITY flag for devices that mux MSIs onto a single IRQ line and cannot set the affinity of each MSI to a specific CPU core (Marek Vasut) - Use MSI_FLAG_NO_AFFINITY and remove unnecessary .irq_set_affinity() implementations in aardvark, altera, brcmstb, dwc, mediatek-gen3, mediatek, mobiveil, plda, rcar, tegra, vmd, xilinx-nwl, xilinx-xdma, and xilinx drivers to avoid 'IRQ: set affinity failed' warnings (Marek Vasut) Power management: - Add pwrctl support for ATH11K inside the WCN6855 package (Konrad Dybcio) PCI device hotplug: - Remove unnecessary hpc_ops struct from shpchp (ngn) - Check for PCI_POSSIBLE_ERROR(), not 0xffffffff, in cpqphp (weiyufeng) Virtualization: - Mark Creative Labs EMU20k2 INTx masking as broken (Alex Williamson) - Add an ACS quirk for Qualcomm SA8775P, which doesn't advertise ACS but does provide ACS-like features (Subramanian Ananthanarayanan) IOMMU: - Add function 0 DMA alias quirk for Glenfly Arise audio function, which uses the function 0 Requester ID (WangYuli) NPEM: - Add Native PCIe Enclosure Management (NPEM) support for sysfs control of NVMe RAID storage indicators (ok/fail/locate/ rebuild/etc) (Mariusz Tkaczyk) - Add support for the ACPI _DSM PCIe SSD status LED management, which is functionally similar to NPEM but mediated by platform firmware (Mariusz Tkaczyk) Device trees: - Drop minItems and maxItems from ranges in PCI generic host binding since host bridges may have several MMIO and I/O port apertures (Frank Li) - Add kirin, rcar-gen2, uniphier DT binding top-level constraints for clocks (Krzysztof Kozlowski) Altera PCIe controller driver: - Convert altera DT bindings from text to YAML (Matthew Gerlach) - Replace TLP_REQ_ID() with macro PCI_DEVID(), which does the same thing and is what other drivers use (Jinjie Ruan) Broadcom STB PCIe controller driver: - Add DT binding maxItems for reset controllers (Jim Quinlan) - Use the 'bridge' reset method if described in the DT (Jim Quinlan) - Use the 'swinit' reset method if described in the DT (Jim Quinlan) - Add 'has_phy' so the existence of a 'rescal' reset controller doesn't imply software control of it (Jim Quinlan) - Add support for many inbound DMA windows (Jim Quinlan) - Rename SoC 'type' to 'soc_base' express the fact that SoCs come in families of multiple similar devices (Jim Quinlan) - Add Broadcom 7712 DT description and driver support (Jim Quinlan) - Sort enums, pcie_offsets[], pcie_cfg_data, .compatible strings for maintainability (Bjorn Helgaas) Freescale i.MX6 PCIe controller driver: - Add imx6q-pcie 'dbi2' and 'atu' reg-names for i.MX8M Endpoints (Richard Zhu) - Fix a code restructuring error that caused i.MX8MM and i.MX8MP Endpoints to fail to establish link (Richard Zhu) - Fix i.MX8MP Endpoint occasional failure to trigger MSI by enforcing outbound alignment requirement (Richard Zhu) - Call phy_power_off() in the .probe() error path (Frank Li) - Rename internal names from imx6_* to imx_* since i.MX7/8/9 are also supported (Frank Li) - Manage Refclk by using SoC-specific callbacks instead of switch statements (Frank Li) - Manage core reset by using SoC-specific callbacks instead of switch statements (Frank Li) - Expand comments for erratum ERR010728 workaround (Frank Li) - Use generic PHY APIs to configure mode, speed, and submode, which is harmless for devices that implement their own internal PHY management and don't set the generic imx_pcie->phy (Frank Li) - Add i.MX8Q (i.MX8QM, i.MX8QXP, and i.MX8DXL) DT binding and driver Root Complex support (Richard Zhu) Freescale Layerscape PCIe controller driver: - Replace layerscape-pcie DT binding compatible fsl,lx2160a-pcie with fsl,lx2160ar2-pcie (Frank Li) - Add layerscape-pcie DT binding deprecated 'num-viewport' property to address a DT checker warning (Frank Li) - Change layerscape-pcie DT binding 'fsl,pcie-scfg' to phandle-array (Frank Li) Loongson PCIe controller driver: - Increase max PCI hosts to 8 for Loongson-3C6000 and newer chipsets (Huacai Chen) Marvell Aardvark PCIe controller driver: - Fix issue with emulating Configuration RRS for two-byte reads of Vendor ID; previously it only worked for four-byte reads (Bjorn Helgaas) MediaTek PCIe Gen3 controller driver: - Add per-SoC struct mtk_gen3_pcie_pdata to support multiple SoC types (Lorenzo Bianconi) - Use reset_bulk APIs to manage PHY reset lines (Lorenzo Bianconi) - Add DT and driver support for Airoha EN7581 PCIe controller (Lorenzo Bianconi) Qualcomm PCIe controller driver: - Update qcom,pcie-sc7280 DT binding with eight interrupts (Rayyan Ansari) - Add back DT 'vddpe-3v3-supply', which was incorrectly removed earlier (Johan Hovold) - Drop endpoint redundant masking of global IRQ events (Manivannan Sadhasivam) - Clarify unknown global IRQ message and only log it once to avoid a flood (Manivannan Sadhasivam) - Add 'linux,pci-domain' property to endpoint DT binding (Manivannan Sadhasivam) - Assign PCI domain number for endpoint controllers (Manivannan Sadhasivam) - Add 'qcom_pcie_ep' and the PCI domain number to IRQ names for endpoint controller (Manivannan Sadhasivam) - Add global SPI interrupt for PCIe link events to DT binding (Manivannan Sadhasivam) - Add global RC interrupt handler to handle 'Link up' events and automatically enumerate hot-added devices (Manivannan Sadhasivam) - Avoid mirroring of DBI and iATU register space so it doesn't overlap BAR MMIO space (Prudhvi Yarlagadda) - Enable controller resources like PHY only after PERST# is deasserted to partially avoid the problem that the endpoint SoC crashes when accessing things when Refclk is absent (Manivannan Sadhasivam) - Add 16.0 GT/s equalization and RX lane margining settings (Shashank Babu Chinta Venkata) - Pass domain number to pci_bus_release_domain_nr() explicitly to avoid a NULL pointer dereference (Manivannan Sadhasivam) Renesas R-Car PCIe controller driver: - Make the read-only const array 'check_addr' static (Colin Ian King) - Add R-Car V4M (R8A779H0) PCIe host and endpoint to DT binding (Yoshihiro Shimoda) TI DRA7xx PCIe controller driver: - Request IRQF_ONESHOT for 'dra7xx-pcie-main' IRQ since the primary handler is NULL (Siddharth Vadapalli) - Handle IRQ request errors during root port and endpoint probe (Siddharth Vadapalli) TI J721E PCIe driver: - Add DT 'ti,syscon-acspcie-proxy-ctrl' and driver support to enable the ACSPCIE module to drive Refclk for the Endpoint (Siddharth Vadapalli) - Extract the cadence link setup from cdns_pcie_host_setup() so link setup can be done separately during resume (Thomas Richard) - Add T_PERST_CLK_US definition for the mandatory delay between Refclk becoming stable and PERST# being deasserted (Thomas Richard) - Add j721e suspend and resume support (Théo Lebrun) TI Keystone PCIe controller driver: - Fix NULL pointer checking when applying MRRS limitation quirk for AM65x SR 1.0 Errata #i2037 (Dan Carpenter) Xilinx NWL PCIe controller driver: - Fix off-by-one error in INTx IRQ handler that caused INTx interrupts to be lost or delivered as the wrong interrupt (Sean Anderson) - Rate-limit misc interrupt messages (Sean Anderson) - Turn off the clock on probe failure and device removal (Sean Anderson) - Add DT binding and driver support for enabling/disabling PHYs (Sean Anderson) - Add PCIe phy bindings for the ZCU102 (Sean Anderson) Xilinx XDMA PCIe controller driver: - Add support for Xilinx QDMA Soft IP PCIe Root Port Bridge to DT binding and xilinx-dma-pl driver (Thippeswamy Havalige) Miscellaneous: - Fix buffer overflow in kirin_pcie_parse_port() (Alexandra Diupina) - Fix minor kerneldoc issues and typos (Bjorn Helgaas) - Use PCI_DEVID() macro in aer_inject() instead of open-coding it (Jinjie Ruan) - Check pcie_find_root_port() return in x86 fixups to avoid NULL pointer dereferences (Samasth Norway Ananda) - Make pci_bus_type constant (Kunwu Chan) - Remove unused declarations of __pci_pme_wakeup() and pci_vpd_release() (Yue Haibing) - Remove any leftover .*.cmd files with make clean (zhang jiao) - Remove unused BILLION macro (zhang jiao)" * tag 'pci-v6.12-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/pci/pci: (132 commits) PCI: Fix typos dt-bindings: PCI: qcom: Allow 'vddpe-3v3-supply' again tools: PCI: Remove unused BILLION macro tools: PCI: Remove .*.cmd files with make clean PCI: Pass domain number to pci_bus_release_domain_nr() explicitly PCI: dra7xx: Fix error handling when IRQ request fails in probe PCI: dra7xx: Fix threaded IRQ request for "dra7xx-pcie-main" IRQ PCI: qcom: Add RX lane margining settings for 16.0 GT/s PCI: qcom: Add equalization settings for 16.0 GT/s PCI: dwc: Always cache the maximum link speed value in dw_pcie::max_link_speed PCI: dwc: Rename 'dw_pcie::link_gen' to 'dw_pcie::max_link_speed' PCI: qcom-ep: Enable controller resources like PHY only after refclk is available PCI: Mark Creative Labs EMU20k2 INTx masking as broken dt-bindings: PCI: imx6q-pcie: Add reg-name "dbi2" and "atu" for i.MX8M PCIe Endpoint dt-bindings: PCI: altera: msi: Convert to YAML PCI: imx6: Add i.MX8Q PCIe Root Complex (RC) support PCI: Rename CRS Completion Status to RRS PCI: aardvark: Correct Configuration RRS checking PCI: Wait for device readiness with Configuration RRS PCI: brcmstb: Sort enums, pcie_offsets[], pcie_cfg_data, .compatible strings ...

Merge branch 'pci/misc'

2024-09-19T19:25:34+00:00

- Check pcie_find_root_port() return in x86 fixups to avoid NULL pointer dereferences (Samasth Norway Ananda) - Make pci_bus_type constant (Kunwu Chan) - Remove unused declarations of __pci_pme_wakeup() and pci_vpd_release() (Yue Haibing) - Remove any leftover .*.cmd files with make clean (zhang jiao) * pci/misc: PCI: Fix typos PCI/VPD: Remove pci_vpd_release() unused declarations PCI/PM: Remove __pci_pme_wakeup() unused declarations PCI: Make pci_bus_type constant x86/PCI: Check pcie_find_root_port() return for NULL