kernel.git/drivers/pci/pcie, branch linux-6.16.y

PCI/portdrv: Use is_pciehp instead of is_hotplug_bridge

2025-08-28T14:34:24Z

commit 1d60796a62f327cd9e0a6a0865ded7656d2c67f9 upstream. The PCIe port driver erroneously creates a subdevice for hotplug on ACPI slots which are handled by the ACPI hotplug driver. Avoid by checking the is_pciehp flag instead of is_hotplug_bridge when deciding whether to create a subdevice. The latter encompasses ACPI slots whereas the former doesn't. The superfluous subdevice has no real negative impact, it occupies memory and interrupt resources but otherwise just sits there waiting for interrupts from the slot that are never signaled. Fixes: f8415222837b ("PCI: Use cached copy of PCI_EXP_SLTCAP_HPC bit") Signed-off-by: Lukas Wunner Signed-off-by: Bjorn Helgaas Cc: stable@vger.kernel.org # v4.7+ Link: https://patch.msgid.link/40d5a5fe8d40595d505949c620a067fa110ee85e.1752390102.git.lukas@wunner.de Signed-off-by: Greg Kroah-Hartman

PCI/PTM: Build debugfs code only if CONFIG_DEBUG_FS is enabled

2025-06-23T17:55:49Z

Otherwise, the following build error will happen for CONFIG_DEBUG_FS=n && CONFIG_PCIE_PTM=y: drivers/pci/pcie/ptm.c:498:25: error: redefinition of 'pcie_ptm_create_debugfs' 498 | struct pci_ptm_debugfs *pcie_ptm_create_debugfs(struct device *dev, void *pdata, | ^ ./include/linux/pci.h:1915:2: note: previous definition is here 1915 | *pcie_ptm_create_debugfs(struct device *dev, void *pdata, | ^ drivers/pci/pcie/ptm.c:546:6: error: redefinition of 'pcie_ptm_destroy_debugfs' 546 | void pcie_ptm_destroy_debugfs(struct pci_ptm_debugfs *ptm_debugfs) | ^ ./include/linux/pci.h:1918:1: note: previous definition is here 1918 | pcie_ptm_destroy_debugfs(struct pci_ptm_debugfs *ptm_debugfs) { } | Fixes: 132833405e61 ("PCI: Add debugfs support for exposing PTM context") Reported-by: Eric Biggers Closes: https://lore.kernel.org/linux-pci/20250607025506.GA16607@sol Signed-off-by: Manivannan Sadhasivam Signed-off-by: Bjorn Helgaas Tested-by: Eric Biggers Reviewed-by: Kuppuswamy Sathyanarayanan Link: https://patch.msgid.link/20250608033305.15214-1-manivannan.sadhasivam@linaro.org

Merge branch 'pci/ptm-debugfs'

2025-06-04T15:50:44Z

- Add debugfs support for exposing DWC device-specific PTM context (Manivannan Sadhasivam) * pci/ptm-debugfs: PCI: qcom-ep: Mask PTM_UPDATING interrupt PCI: dwc: Add debugfs support for PTM context PCI: dwc: Pass DWC PCIe mode to dwc_pcie_debugfs_init() PCI: Add debugfs support for exposing PTM context

Merge branch 'pci/bwctrl'

2025-06-04T15:49:49Z

- Simplify link bandwidth controller by replacing the count of Link Bandwidth Management Status (LBMS) events with a PCI_LINK_LBMS_SEEN flag (Ilpo Järvinen) - Update the Link Speed after retraining, since the Link Speed may have changed (Ilpo Järvinen) * pci/bwctrl: PCI: Update Link Speed after retraining PCI/bwctrl: Replace lbms_count with PCI_LINK_LBMS_SEEN flag

PCI/ERR: Remove misleading TODO regarding kernel panic

2025-05-30T17:21:19Z

A PCI device is just another peripheral in a system. So failure to recover it, must not result in a kernel panic. So remove the TODO which is quite misleading. Signed-off-by: Manivannan Sadhasivam Signed-off-by: Krzysztof Wilczyński Signed-off-by: Bjorn Helgaas Reviewed-by: Wilfred Mallawa Link: https://patch.msgid.link/20250508-pcie-reset-slot-v4-1-7050093e2b50@linaro.org

PCI/AER: Add sysfs attributes for log ratelimits

2025-05-23T16:11:45Z

Allow userspace to read/write log ratelimits per device (including enable/disable). Create aer/ sysfs directory to store them and any future AER configs. The new sysfs files are: /sys/bus/pci/devices/*/aer/correctable_ratelimit_burst /sys/bus/pci/devices/*/aer/correctable_ratelimit_interval_ms /sys/bus/pci/devices/*/aer/nonfatal_ratelimit_burst /sys/bus/pci/devices/*/aer/nonfatal_ratelimit_interval_ms The default values are ratelimit_burst=10, ratelimit_interval_ms=5000, so if we try to emit more than 10 messages in a 5 second period, some are suppressed. Update AER sysfs ABI filename to reflect the broader scope of AER sysfs attributes (e.g. stats and ratelimits). Documentation/ABI/testing/sysfs-bus-pci-devices-aer_stats -> sysfs-bus-pci-devices-aer Tested using aer-inject[1]. Configured correctable log ratelimit to 5. Sent 6 AER errors. Observed 5 errors logged while AER stats (cat /sys/bus/pci/devices//aer_dev_correctable) shows 6. Disabled ratelimiting and sent 6 more AER errors. Observed all 6 errors logged and accounted in AER stats (12 total errors). [1] https://git.kernel.org/pub/scm/linux/kernel/git/gong.chen/aer-inject.git [bhelgaas: note fatal errors are not ratelimited, "aer_report" -> "aer_info", replace ratelimit_log_enable toggle with *_ratelimit_interval_ms] Signed-off-by: Karolina Stolarek Signed-off-by: Jon Pan-Doh Signed-off-by: Bjorn Helgaas Reviewed-by: Kuppuswamy Sathyanarayanan Link: https://patch.msgid.link/20250522232339.1525671-21-helgaas@kernel.org

PCI/AER: Ratelimit correctable and non-fatal error logging

2025-05-23T16:11:45Z

Spammy devices can flood kernel logs with AER errors and slow/stall execution. Add per-device ratelimits for AER correctable and non-fatal uncorrectable errors that use the kernel defaults (10 per 5s). Logging of fatal errors is not ratelimited. There are two AER logging entry points: - aer_print_error() is used by DPC and native AER - pci_print_aer() is used by GHES and CXL The native AER aer_print_error() case includes a loop that may log details from multiple devices, which are ratelimited individually. If we log details for any device, we also log the Error Source ID from the Root Port or RCEC. If no such device details are found, we still log the Error Source from the ERR_* Message, ratelimited by the Root Port or RCEC that received it. The DPC aer_print_error() case is not ratelimited, since this only happens for fatal errors. The CXL pci_print_aer() case is ratelimited by the Error Source device. The GHES pci_print_aer() case is via aer_recover_work_func(), which searches for the Error Source device. If the device is not found, there's no per-device ratelimit, so we use a system-wide ratelimit that covers all error types (correctable, non-fatal, and fatal). Sargun at Meta reported internally that a flood of AER errors causes RCU CPU stall warnings and CSD-lock warnings. Tested using aer-inject[1]. Sent 11 AER errors. Observed 10 errors logged while AER stats (cat /sys/bus/pci/devices//aer_dev_correctable) show true count of 11. [1] https://git.kernel.org/pub/scm/linux/kernel/git/gong.chen/aer-inject.git [bhelgaas: commit log, factor out trace_aer_event() and aer_print_rp_info() changes to previous patches, enable Error Source logging if any downstream detail will be printed, don't ratelimit fatal errors, "aer_report" -> "aer_info", "cor_log_ratelimit" -> "correctable_ratelimit", "uncor_log_ratelimit" -> "nonfatal_ratelimit"] Reported-by: Sargun Dhillon Signed-off-by: Jon Pan-Doh Signed-off-by: Bjorn Helgaas Reviewed-by: Kuppuswamy Sathyanarayanan Link: https://patch.msgid.link/20250522232339.1525671-19-helgaas@kernel.org

PCI/AER: Simplify add_error_device()

2025-05-23T16:11:45Z

Return -ENOSPC error early so the usual path through add_error_device() is the straightline code. Signed-off-by: Bjorn Helgaas Reviewed-by: Ilpo Järvinen Reviewed-by: Kuppuswamy Sathyanarayanan Link: https://patch.msgid.link/20250522232339.1525671-18-helgaas@kernel.org

PCI/AER: Convert aer_get_device_error_info(), aer_print_error() to index

2025-05-23T16:11:36Z

Previously aer_get_device_error_info() and aer_print_error() took a pointer to struct aer_err_info and a pointer to a pci_dev. Typically the pci_dev was one of the elements of the aer_err_info.dev[] array (DPC was an exception, where the dev[] array was unused). Convert aer_get_device_error_info() and aer_print_error() to take an index into the aer_err_info.dev[] array instead. A future patch will add per-device ratelimit information, so the index makes it convenient to find the ratelimit associated with the device. To accommodate DPC, set info->dev[0] to the DPC port before using these interfaces. Signed-off-by: Bjorn Helgaas Reviewed-by: Ilpo Järvinen Reviewed-by: Kuppuswamy Sathyanarayanan Link: https://patch.msgid.link/20250522232339.1525671-17-helgaas@kernel.org

PCI/AER: Rename struct aer_stats to aer_info

2025-05-23T16:02:33Z

Update name to reflect the broader definition of structs/variables that are stored (e.g. ratelimits). This is a preparatory patch for adding rate limit support. [bhelgaas: "aer_report" -> "aer_info"] Signed-off-by: Karolina Stolarek Signed-off-by: Bjorn Helgaas Tested-by: Krzysztof Wilczyński Reviewed-by: Ilpo Järvinen Reviewed-by: Kuppuswamy Sathyanarayanan Reviewed-by: Jonathan Cameron Link: https://patch.msgid.link/20250522232339.1525671-16-helgaas@kernel.org