kernel/linux.git/Documentation/PCI, branch v5.15.209

PCI: endpoint: Automatically create a function specific attributes group

2026-02-19T15:21:46+00:00

[ Upstream commit 70b3740f2c1941e2006d61539131b70d20cba9a6 ] A PCI endpoint function driver can define function specific attributes under its function configfs directory using the add_cfs() endpoint driver operation. This is done by tying up the mkdir operation for the function configfs directory to a call to the add_cfs() operation. However, there are no checks preventing the user from repeatedly creating function specific attribute directories with different names, resulting in the same endpoint specific attributes group being added multiple times, which also result in an invalid reference counting for the attribute groups. E.g., using the pci-epf-ntb function driver as an example, the user creates the function as follows: $ modprobe pci-epf-ntb $ cd /sys/kernel/config/pci_ep/functions/pci_epf_ntb $ mkdir func0 $ tree func0 func0/ |-- baseclass_code |-- cache_line_size |-- ... `-- vendorid $ mkdir func0/attrs $ tree func0 func0/ |-- attrs | |-- db_count | |-- mw1 | |-- mw2 | |-- mw3 | |-- mw4 | |-- num_mws | `-- spad_count |-- baseclass_code |-- cache_line_size |-- ... `-- vendorid At this point, the function can be started by linking the EP controller. However, if the user mistakenly creates again a directory: $ mkdir func0/attrs2 $ tree func0 func0/ |-- attrs | |-- db_count | |-- mw1 | |-- mw2 | |-- mw3 | |-- mw4 | |-- num_mws | `-- spad_count |-- attrs2 | |-- db_count | |-- mw1 | |-- mw2 | |-- mw3 | |-- mw4 | |-- num_mws | `-- spad_count |-- baseclass_code |-- cache_line_size |-- ... `-- vendorid The endpoint function specific attributes are duplicated and cause a crash when the endpoint function device is torn down: refcount_t: addition on 0; use-after-free. WARNING: CPU: 2 PID: 834 at lib/refcount.c:25 refcount_warn_saturate+0xc8/0x144 CPU: 2 PID: 834 Comm: rmdir Not tainted 6.3.0-rc1 #1 Hardware name: Pine64 RockPro64 v2.1 (DT) pstate: 60000005 (nZCv daif -PAN -UAO -TCO -DIT -SSBS BTYPE=--) ... Call trace: refcount_warn_saturate+0xc8/0x144 config_item_get+0x7c/0x80 configfs_rmdir+0x17c/0x30c vfs_rmdir+0x8c/0x204 do_rmdir+0x158/0x184 __arm64_sys_unlinkat+0x64/0x80 invoke_syscall+0x48/0x114 ... Fix this by modifying pci_epf_cfs_work() to execute the new function pci_ep_cfs_add_type_group() which itself calls pci_epf_type_add_cfs() to obtain the function specific attribute group and the group name (directory name) from the endpoint function driver. If the function driver defines an attribute group, pci_ep_cfs_add_type_group() then proceeds to register this group using configfs_register_group(), thus automatically exposing the function type specific configfs attributes to the user. E.g.: $ modprobe pci-epf-ntb $ cd /sys/kernel/config/pci_ep/functions/pci_epf_ntb $ mkdir func0 $ tree func0 func0/ |-- baseclass_code |-- cache_line_size |-- ... |-- pci_epf_ntb.0 | |-- db_count | |-- mw1 | |-- mw2 | |-- mw3 | |-- mw4 | |-- num_mws | `-- spad_count |-- primary |-- ... `-- vendorid With this change, there is no need for the user to create or delete directories in the endpoint function attributes directory. The pci_epf_type_group_ops group operations are thus removed. Also update the documentation for the pci-epf-ntb and pci-epf-vntb function drivers to reflect this change, removing the explanations showing the need to manually create the sub-directory for the function specific attributes. Link: https://lore.kernel.org/r/20230415023542.77601-2-dlemoal@kernel.org Signed-off-by: Damien Le Moal Signed-off-by: Lorenzo Pieralisi Signed-off-by: Bjorn Helgaas Reviewed-by: Manivannan Sadhasivam Stable-dep-of: 7c5c7d06bd1f ("PCI: endpoint: Avoid creating sub-groups asynchronously") Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman

Merge tag 'pci-v5.15-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci

2021-09-08T02:13:42+00:00

Pull PCI updates from Bjorn Helgaas: "Enumeration: - Convert controller drivers to generic_handle_domain_irq() (Marc Zyngier) - Simplify VPD (Vital Product Data) access and search (Heiner Kallweit) - Update bnx2, bnx2x, bnxt, cxgb4, cxlflash, sfc, tg3 drivers to use simplified VPD interfaces (Heiner Kallweit) - Run Max Payload Size quirks before configuring MPS; work around ASMedia ASM1062 SATA MPS issue (Marek Behún) Resource management: - Refactor pci_ioremap_bar() and pci_ioremap_wc_bar() (Krzysztof Wilczyński) - Optimize pci_resource_len() to reduce kernel size (Zhen Lei) PCI device hotplug: - Fix a double unmap in ibmphp (Vishal Aslot) PCIe port driver: - Enable Bandwidth Notification only if port supports it (Stuart Hayes) Sysfs/proc/syscalls: - Add schedule point in proc_bus_pci_read() (Krzysztof Wilczyński) - Return ~0 data on pciconfig_read() CAP_SYS_ADMIN failure (Krzysztof Wilczyński) - Return "int" from pciconfig_read() syscall (Krzysztof Wilczyński) Virtualization: - Extend "pci=noats" to also turn on Translation Blocking to protect against some DMA attacks (Alex Williamson) - Add sysfs mechanism to control the type of reset used between device assignments to VMs (Amey Narkhede) - Add support for ACPI _RST reset method (Shanker Donthineni) - Add ACS quirks for Cavium multi-function devices (George Cherian) - Add ACS quirks for NXP LX2xx0 and LX2xx2 platforms (Wasim Khan) - Allow HiSilicon AMBA devices that appear as fake PCI devices to use PASID and SVA (Zhangfei Gao) Endpoint framework: - Add support for SR-IOV Endpoint devices (Kishon Vijay Abraham I) - Zero-initialize endpoint test tool parameters so we don't use random parameters (Shunyong Yang) APM X-Gene PCIe controller driver: - Remove redundant dev_err() call in xgene_msi_probe() (ErKun Yang) Broadcom iProc PCIe controller driver: - Don't fail devm_pci_alloc_host_bridge() on missing 'ranges' because it's optional on BCMA devices (Rob Herring) - Fix BCMA probe resource handling (Rob Herring) Cadence PCIe driver: - Work around J7200 Link training electrical issue by increasing delays in LTSSM (Nadeem Athani) Intel IXP4xx PCI controller driver: - Depend on ARCH_IXP4XX to avoid useless config questions (Geert Uytterhoeven) Intel Keembay PCIe controller driver: - Add Intel Keem Bay PCIe controller (Srikanth Thokala) Marvell Aardvark PCIe controller driver: - Work around config space completion handling issues (Evan Wang) - Increase timeout for config access completions (Pali Rohár) - Emulate CRS Software Visibility bit (Pali Rohár) - Configure resources from DT 'ranges' property to fix I/O space access (Pali Rohár) - Serialize INTx mask/unmask (Pali Rohár) MediaTek PCIe controller driver: - Add MT7629 support in DT (Chuanjia Liu) - Fix an MSI issue (Chuanjia Liu) - Get syscon regmap ("mediatek,generic-pciecfg"), IRQ number ("pci_irq"), PCI domain ("linux,pci-domain") from DT properties if present (Chuanjia Liu) Microsoft Hyper-V host bridge driver: - Add ARM64 support (Boqun Feng) - Support "Create Interrupt v3" message (Sunil Muthuswamy) NVIDIA Tegra PCIe controller driver: - Use seq_puts(), move err_msg from stack to static, fix OF node leak (Christophe JAILLET) NVIDIA Tegra194 PCIe driver: - Disable suspend when in Endpoint mode (Om Prakash Singh) - Fix MSI-X address programming error (Om Prakash Singh) - Disable interrupts during suspend to avoid spurious AER link down (Om Prakash Singh) Renesas R-Car PCIe controller driver: - Work around hardware issue that prevents Link L1->L0 transition (Marek Vasut) - Fix runtime PM refcount leak (Dinghao Liu) Rockchip DesignWare PCIe controller driver: - Add Rockchip RK356X host controller driver (Simon Xue) TI J721E PCIe driver: - Add support for J7200 and AM64 (Kishon Vijay Abraham I) Toshiba Visconti PCIe controller driver: - Add Toshiba Visconti PCIe host controller driver (Nobuhiro Iwamatsu) Xilinx NWL PCIe controller driver: - Enable PCIe reference clock via CCF (Hyun Kwon) Miscellaneous: - Convert sta2x11 from 'pci_' to 'dma_' API (Christophe JAILLET) - Fix pci_dev_str_match_path() alloc while atomic bug (used for kernel parameters that specify devices) (Dan Carpenter) - Remove pointless Precision Time Management warning when PTM is present but not enabled (Jakub Kicinski) - Remove surplus "break" statements (Krzysztof Wilczyński)" * tag 'pci-v5.15-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci: (132 commits) PCI: ibmphp: Fix double unmap of io_mem x86/PCI: sta2x11: switch from 'pci_' to 'dma_' API PCI/VPD: Use unaligned access helpers PCI/VPD: Clean up public VPD defines and inline functions cxgb4: Use pci_vpd_find_id_string() to find VPD ID string PCI/VPD: Add pci_vpd_find_id_string() PCI/VPD: Include post-processing in pci_vpd_find_tag() PCI/VPD: Stop exporting pci_vpd_find_info_keyword() PCI/VPD: Stop exporting pci_vpd_find_tag() PCI: Set dma-can-stall for HiSilicon chips PCI: rockchip-dwc: Add Rockchip RK356X host controller driver PCI: dwc: Remove surplus break statement after return PCI: artpec6: Remove local code block from switch statement PCI: artpec6: Remove surplus break statement after return MAINTAINERS: Add entries for Toshiba Visconti PCIe controller PCI: visconti: Add Toshiba Visconti PCIe host controller driver PCI/portdrv: Enable Bandwidth Notification only if port supports it PCI: Allow PASID on fake PCIe devices without TLP prefixes PCI: mediatek: Use PCI domain to handle ports detection PCI: mediatek: Add new method to get irq number ...

PCI: Add 'override_only' field to struct pci_device_id

2021-08-26T16:36:51+00:00

Add 'override_only' field to struct pci_device_id to be used as part of pci_match_device(). When set, a driver only matches the entry when dev->driver_override is set to that driver. In addition, add a helper macro named 'PCI_DEVICE_DRIVER_OVERRIDE' to enable setting some data on it. Next patch from this series will use the above functionality. Signed-off-by: Max Gurtovoy Signed-off-by: Jason Gunthorpe Acked-by: Bjorn Helgaas Signed-off-by: Yishai Hadas Link: https://lore.kernel.org/r/20210826103912.128972-10-yishaih@nvidia.com Signed-off-by: Alex Williamson

Documentation: PCI: endpoint/pci-endpoint-cfs: Guide to use SR-IOV

2021-08-19T13:13:29+00:00

Add Documentation to help users use PCI endpoint to create virtual functions using configfs. An endpoint function is designated as a virtual endpoint function device when it is linked to a physical endpoint function device (instead of a endpoint controller). Link: https://lore.kernel.org/r/20210819123343.1951-9-kishon@ti.com Signed-off-by: Kishon Vijay Abraham I Signed-off-by: Lorenzo Pieralisi

Merge tag 'pci-v5.14-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci

2021-07-08T19:06:20+00:00

Pull pci updates from Bjorn Helgaas: "Enumeration: - Fix dsm_label_utf16s_to_utf8s() buffer overrun (Krzysztof Wilczyński) - Rely on lengths from scnprintf(), dsm_label_utf16s_to_utf8s() (Krzysztof Wilczyński) - Use sysfs_emit() and sysfs_emit_at() in "show" functions (Krzysztof Wilczyński) - Fix 'resource_alignment' newline issues (Krzysztof Wilczyński) - Add 'devspec' newline (Krzysztof Wilczyński) - Dynamically map ECAM regions (Russell King) Resource management: - Coalesce host bridge contiguous apertures (Kai-Heng Feng) PCIe native device hotplug: - Ignore Link Down/Up caused by DPC (Lukas Wunner) Power management: - Leave Apple Thunderbolt controllers on for s2idle or standby (Konstantin Kharlamov) Virtualization: - Work around Huawei Intelligent NIC VF FLR erratum (Chiqijun) - Clarify error message for unbound IOV devices (Moritz Fischer) - Add pci_reset_bus_function() Secondary Bus Reset interface (Raphael Norwitz) Peer-to-peer DMA: - Simplify distance calculation (Christoph Hellwig) - Finish RCU conversion of pdev->p2pdma (Eric Dumazet) - Rename upstream_bridge_distance() and rework doc (Logan Gunthorpe) - Collect acs list in stack buffer to avoid sleeping (Logan Gunthorpe) - Use correct calc_map_type_and_dist() return type (Logan Gunthorpe) - Warn if host bridge not in whitelist (Logan Gunthorpe) - Refactor pci_p2pdma_map_type() (Logan Gunthorpe) - Avoid pci_get_slot(), which may sleep (Logan Gunthorpe) Altera PCIe controller driver: - Add Joyce Ooi as Altera PCIe maintainer (Joyce Ooi) Broadcom iProc PCIe controller driver: - Fix multi-MSI base vector number allocation (Sandor Bodo-Merle) - Support multi-MSI only on uniprocessor kernel (Sandor Bodo-Merle) Freescale i.MX6 PCIe controller driver: - Limit DBI register length for imx6qp PCIe (Richard Zhu) - Add "vph-supply" for PHY supply voltage (Richard Zhu) - Enable PHY internal regulator when supplied >3V (Richard Zhu) - Remove imx6_pcie_probe() redundant error message (Zhen Lei) Intel Gateway PCIe controller driver: - Fix INTx enable (Martin Blumenstingl) Marvell Aardvark PCIe controller driver: - Fix checking for PIO Non-posted Request (Pali Rohár) - Implement workaround for the readback value of VEND_ID (Pali Rohár) MediaTek PCIe controller driver: - Remove redundant error printing in mtk_pcie_subsys_powerup() (Zhen Lei) MediaTek PCIe Gen3 controller driver: - Add missing MODULE_DEVICE_TABLE (Zou Wei) Microchip PolarFlare PCIe controller driver: - Make struct event_descs static (Krzysztof Wilczyński) Microsoft Hyper-V host bridge driver: - Fix race condition when removing the device (Long Li) - Remove bus device removal unused refcount/functions (Long Li) Mobiveil PCIe controller driver: - Remove unused readl and writel functions (Krzysztof Wilczyński) NVIDIA Tegra PCIe controller driver: - Add missing MODULE_DEVICE_TABLE (Zou Wei) NVIDIA Tegra194 PCIe controller driver: - Fix tegra_pcie_ep_raise_msi_irq() ill-defined shift (Jon Hunter) - Fix host initialization during resume (Vidya Sagar) Rockchip PCIe controller driver: - Register IRQ handlers after device and data are ready (Javier Martinez Canillas)" * tag 'pci-v5.14-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci: (48 commits) PCI/P2PDMA: Finish RCU conversion of pdev->p2pdma PCI: xgene: Annotate __iomem pointer PCI: Fix kernel-doc formatting PCI: cpcihp: Declare cpci_debug in header file MAINTAINERS: Add Joyce Ooi as Altera PCIe maintainer PCI: rockchip: Register IRQ handlers after device and data are ready PCI: tegra194: Fix tegra_pcie_ep_raise_msi_irq() ill-defined shift PCI: aardvark: Implement workaround for the readback value of VEND_ID PCI: aardvark: Fix checking for PIO Non-posted Request PCI: tegra194: Fix host initialization during resume PCI: tegra: Add missing MODULE_DEVICE_TABLE PCI: imx6: Enable PHY internal regulator when supplied >3V dt-bindings: imx6q-pcie: Add "vph-supply" for PHY supply voltage PCI: imx6: Limit DBI register length for imx6qp PCIe PCI: imx6: Remove imx6_pcie_probe() redundant error message PCI: intel-gw: Fix INTx enable PCI: iproc: Support multi-MSI only on uniprocessor kernel PCI: iproc: Fix multi-MSI base vector number allocation PCI: mediatek-gen3: Add missing MODULE_DEVICE_TABLE PCI: Dynamically map ECAM regions ...

docs: PCI: pci.rst: avoid using ReST :doc:`foo` markup

2021-06-17T19:24:38+00:00

The :doc:`foo` tag is auto-generated via automarkup.py. So, use the filename at the sources, instead of :doc:`foo`. Signed-off-by: Mauro Carvalho Chehab Acked-by: Bjorn Helgaas Link: https://lore.kernel.org/r/8697cf945390f6b45fefb4c5fe22ed1c8070e32e.1623824363.git.mchehab+huawei@kernel.org Signed-off-by: Jonathan Corbet

docs: PCI: endpoint: pci-endpoint-cfs.rst: avoid using ReST :doc:`foo` markup

2021-06-17T19:24:38+00:00

The :doc:`foo` tag is auto-generated via automarkup.py. So, use the filename at the sources, instead of :doc:`foo`. Acked-by: Bjorn Helgaas Signed-off-by: Mauro Carvalho Chehab Link: https://lore.kernel.org/r/4b18febe4a4f030dd9d43e5e6a2a0aa28bd5b734.1623824363.git.mchehab+huawei@kernel.org Signed-off-by: Jonathan Corbet

docs: PCI: Replace non-breaking spaces to avoid PDF issues

2021-06-17T19:22:33+00:00

The conversion tools used during DocBook/LaTeX/html/Markdown->ReST conversion and some cut-and-pasted text contain some characters that aren't easily reachable on standard keyboards and/or could cause troubles when parsed by the documentation build system. Replace the occurences of the following characters: - U+00a0 (' '): NO-BREAK SPACE as it can cause lines being truncated on PDF output Acked-by: Bjorn Helgaas Signed-off-by: Mauro Carvalho Chehab Link: https://lore.kernel.org/r/8036126a59adb720dbc9233341ad5a08531cf73f.1623826294.git.mchehab+huawei@kernel.org Signed-off-by: Jonathan Corbet

Documentation: PCI: Fix typo in pci-error-recovery.rst

2021-06-01T16:01:40+00:00

Replace "It" with "If", since it is a conditional statement. Link: https://lore.kernel.org/r/20210531081215.43507-1-wesley.sheng@amd.com Signed-off-by: Wesley Sheng Signed-off-by: Bjorn Helgaas Reviewed-by: Krzysztof Wilczyński

Documentation: PCI: Add PCI endpoint NTB function user guide

2021-02-23T20:15:45+00:00

Add documentation to help users use pci-epf-ntb function driver and existing host side NTB infrastructure for NTB functionality. [bhelgaas: fix a few typos] Link: https://lore.kernel.org/r/20210201195809.7342-18-kishon@ti.com Signed-off-by: Kishon Vijay Abraham I Signed-off-by: Lorenzo Pieralisi Signed-off-by: Bjorn Helgaas Reviewed-by: Randy Dunlap