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2025-09-25PCI: tegra: Convert struct tegra_msi mask_lock into raw spinlockMarek Vasut
The tegra_msi_irq_unmask() function may be called from a PCI driver request_threaded_irq() function. This triggers kernel/irq/manage.c __setup_irq() which locks raw spinlock &desc->lock descriptor lock and with that descriptor lock held, calls tegra_msi_irq_unmask(). Since the &desc->lock descriptor lock is a raw spinlock, and the tegra_msi .mask_lock is not a raw spinlock, this setup triggers 'BUG: Invalid wait context' with CONFIG_PROVE_RAW_LOCK_NESTING=y. Use scoped_guard() to simplify the locking. Fixes: 2c99e55f7955 ("PCI: tegra: Convert to MSI domains") Reported-by: Geert Uytterhoeven <geert+renesas@glider.be> Closes: https://patchwork.kernel.org/project/linux-pci/patch/20250909162707.13927-2-marek.vasut+renesas@mailbox.org/#26574451 Signed-off-by: Marek Vasut <marek.vasut+renesas@mailbox.org> Signed-off-by: Manivannan Sadhasivam <mani@kernel.org> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Cc: stable@vger.kernel.org Link: https://patch.msgid.link/20250922150811.88450-1-marek.vasut+renesas@mailbox.org
2025-09-25PCI: rcar-gen4: Fix inverted break condition in PHY initializationMarek Vasut
R-Car V4H Reference Manual R19UH0186EJ0130 Rev.1.30 Apr. 21, 2025 page 4581 Figure 104.3b Initial Setting of PCIEC(example), third quarter of the figure indicates that register 0xf8 should be polled until bit 18 becomes set to 1. Register 0xf8, bit 18 is 0 immediately after write to PCIERSTCTRL1 and is set to 1 in less than 1 ms afterward. The current readl_poll_timeout() break condition is inverted and returns when register 0xf8, bit 18 is set to 0, which in most cases means immediately. In case CONFIG_DEBUG_LOCK_ALLOC=y, the timing changes just enough for the first readl_poll_timeout() poll to already read register 0xf8, bit 18 as 1 and afterward never read register 0xf8, bit 18 as 0, which leads to timeout and failure to start the PCIe controller. Fix this by inverting the poll condition to match the reference manual initialization sequence. Fixes: faf5a975ee3b ("PCI: rcar-gen4: Add support for R-Car V4H") Signed-off-by: Marek Vasut <marek.vasut+renesas@mailbox.org> Signed-off-by: Manivannan Sadhasivam <mani@kernel.org> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Tested-by: Geert Uytterhoeven <geert+renesas@glider.be> Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be> Link: https://patch.msgid.link/20250915235910.47768-1-marek.vasut+renesas@mailbox.org
2025-09-25PCI: rcar-gen4: Assure reset occurs before DBI accessMarek Vasut
Assure the reset is latched and the core is ready for DBI access. On R-Car V4H, the PCIe reset is asynchronous and does not take effect immediately, but needs a short time to complete. In case DBI access happens in that short time, that access generates an SError. Make sure that condition can never happen, read back the state of the reset, which should turn the asynchronous reset into a synchronous one, and wait a little over 1ms to add additional safety margin. Fixes: 0d0c551011df ("PCI: rcar-gen4: Add R-Car Gen4 PCIe controller support for host mode") Signed-off-by: Marek Vasut <marek.vasut+renesas@mailbox.org> Signed-off-by: Manivannan Sadhasivam <mani@kernel.org> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Tested-by: Geert Uytterhoeven <geert+renesas@glider.be> Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be> Link: https://patch.msgid.link/20250924005610.96484-1-marek.vasut+renesas@mailbox.org
2025-09-25PCI: rcar-gen4: Add missing 1ms delay after PWR reset assertionMarek Vasut
R-Car V4H Reference Manual R19UH0186EJ0130 Rev.1.30 Apr. 21, 2025 page 585 Figure 9.3.2 Software Reset flow (B) indicates that for peripherals in HSC domain, after reset has been asserted by writing a matching reset bit into register SRCR, it is mandatory to wait 1ms. Because it is the controller driver which can determine whether or not the controller is in HSC domain based on its compatible string, add the missing delay in the controller driver. This 1ms delay is documented on R-Car V4H and V4M; it is currently unclear whether S4 is affected as well. This patch does apply the extra delay on R-Car S4 as well. Fixes: 0d0c551011df ("PCI: rcar-gen4: Add R-Car Gen4 PCIe controller support for host mode") Suggested-by: Geert Uytterhoeven <geert@linux-m68k.org> Signed-off-by: Marek Vasut <marek.vasut+renesas@mailbox.org> [mani: added the missing r-b tag from Krzysztof] Signed-off-by: Manivannan Sadhasivam <mani@kernel.org> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be> Reviewed-by: Krzysztof Wilczyński <kwilczynski@kernel.org> Link: https://patch.msgid.link/20250919134644.208098-1-marek.vasut+renesas@mailbox.org
2025-09-25PCI: Set up bridge resources earlierIlpo Järvinen
Bridge windows are read twice from PCI Config Space, the first time from pci_read_bridge_windows(), which does not set up the device's resources. This causes problems down the road as child resources of the bridge cannot check whether they reside within the bridge window or not. Set up the bridge windows already in pci_read_bridge_windows(). Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Link: https://patch.msgid.link/20250924134228.1663-2-ilpo.jarvinen@linux.intel.com
2025-09-25Merge tag 'thunderbolt-for-v6.18-rc1' of ↵Greg Kroah-Hartman
ssh://gitolite.kernel.org/pub/scm/linux/kernel/git/westeri/thunderbolt into usb-next Mika writes: thunderbolt: Changes for v6.18 merge window This includes following USB4/Thunderbolt changes for the v6.18 merge window: - HMAC hashing improvements - Switch to use Linux Foundation IDs for XDomain discovery - Use is_pciehp instead of is_hotplug_bridge - Fixes for various kernel-doc issues - Fix use-after-free in DP tunneling error path. I'm sending the UAF fix with this pull request because it came quite late and I would like to give it some exposure before it lands the mainline. All these except the UAF fix have been in linux-next with no reported issues. * tag 'thunderbolt-for-v6.18-rc1' of ssh://gitolite.kernel.org/pub/scm/linux/kernel/git/westeri/thunderbolt: (33 commits) thunderbolt: Fix use-after-free in tb_dp_dprx_work thunderbolt: Update thunderbolt.h header file thunderbolt: Update xdomain.c function documentation thunderbolt: Update usb4_port.c function documentation thunderbolt: Update usb4.c function documentation thunderbolt: Update tunnel.h function documentation thunderbolt: Update tunnel.c function documentation thunderbolt: Update tmu.c function documentation thunderbolt: Add missing documentation in tb.h thunderbolt: Update tb.h function documentation thunderbolt: Update tb.c function documentation thunderbolt: Update switch.c function documentation thunderbolt: Update retimer.c function documentation thunderbolt: Update property.c function documentation thunderbolt: Update path.c function documentation thunderbolt: Update nvm.c function documentation thunderbolt: Add missing documentation in nhi_regs.h ring_desc structure thunderbolt: Update nhi.c function documentation thunderbolt: Update lc.c function documentation thunderbolt: Update eeprom.c function documentation ...
2025-09-25PCI: rcar-host: Drop PMSR spinlockMarek Vasut
The pmsr_lock spinlock used to be necessary to synchronize access to the PMSR register, because that access could have been triggered from either config space access in rcar_pcie_config_access() or an exception handler rcar_pcie_aarch32_abort_handler(). The rcar_pcie_aarch32_abort_handler() case is no longer applicable since commit 6e36203bc14c ("PCI: rcar: Use PCI_SET_ERROR_RESPONSE after read which triggered an exception"), which performs more accurate, controlled invocation of the exception, and a fixup. This leaves rcar_pcie_config_access() as the only call site from which rcar_pcie_wakeup() is called. The rcar_pcie_config_access() can only be called from the controller struct pci_ops .read and .write callbacks, and those are serialized in drivers/pci/access.c using raw spinlock 'pci_lock' . It should be noted that CONFIG_PCI_LOCKLESS_CONFIG is never set on this platform. Since the 'pci_lock' is a raw spinlock , and the 'pmsr_lock' is not a raw spinlock, this constellation triggers 'BUG: Invalid wait context' with CONFIG_PROVE_RAW_LOCK_NESTING=y . Remove the pmsr_lock to fix the locking. Fixes: a115b1bd3af0 ("PCI: rcar: Add L1 link state fix into data abort hook") Reported-by: Duy Nguyen <duy.nguyen.rh@renesas.com> Reported-by: Thuan Nguyen <thuan.nguyen-hong@banvien.com.vn> Signed-off-by: Marek Vasut <marek.vasut+renesas@mailbox.org> Signed-off-by: Manivannan Sadhasivam <mani@kernel.org> Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be> Cc: stable@vger.kernel.org Link: https://patch.msgid.link/20250909162707.13927-1-marek.vasut+renesas@mailbox.org
2025-09-25PCI: dwc: Support ECAM mechanism by enabling iATU 'CFG Shift Feature'Krishna Chaitanya Chundru
Designware databook r5.20a, sec 3.10.10.3 documents the 'CFG Shift Feature' of the internal Address Translation Unit (iATU). When this feature is enabled, it shifts/maps the BDF contained in the bits [27:12] of the target address in MEM TLP to become BDF of the CFG TLP. This essentially implements the Enhanced Configuration Address Mapping (ECAM) mechanism as defined in PCIe r6.0, sec 7.2.2. Currently, the driver is not making use of this CFG shift feature, thereby creating the iATU outbound map for each config access to the devices, causing latency and wasting CPU cycles. So to avoid this, configure the controller to enable CFG shift feature by enabling the 'CFG Shift' bit of the 'iATU Control 2 Register'. As a result of enabling CFG shift (ECAM), there is no longer a need to map the DBI register space separately as the DBI region falls under the 'config' space used for ECAM (as DBI is used to access the Root Port). For enabling ECAM using CFG shift, the platform has to satisfy following requirements: 1. Size of the 'config' memory space to be used as ECAM memory should be able to accommodate the number of buses defined in the 'bus-range' property of the host bridge DT node. 2. The 'config' memory space should be 256 MiB aligned. This requirement comes from PCIe r6.0, sec 7.2.2, which says the base address of ECAM memory should be aligned to a 2^(n+20) byte address boundary. For the DWC cores, n is 8, so this results in 2^28 byte alignment requirement. It should be noted that some DWC vendor glue drivers like pcie-al may use their own ECAM mechanism. For those controllers, set 'dw_pcie_rp::native_ecam' flag and skip enabling the CFG Shift feature in the DWC core. Signed-off-by: Krishna Chaitanya Chundru <krishna.chundru@oss.qualcomm.com> [mani: code split, reworded subject/description, comment, native_ecam flag] Signed-off-by: Manivannan Sadhasivam <mani@kernel.org> Link: https://patch.msgid.link/20250923-controller-dwc-ecam-v10-4-e84390ba75fa@kernel.org
2025-09-25PCI: qcom: Prepare for the DWC ECAM enablementKrishna Chaitanya Chundru
To support the DWC ECAM mechanism, prepare the driver by performing below configurations: 1. Since the ELBI region will be covered by the ECAM 'config' space, override the 'elbi_base' with the address derived from 'dbi_base' and the offset from PARF_SLV_DBI_ELBI register. 2. Block the transactions from the host bridge to devices other than Root Port on the root bus to return all F's. This is required when the 'CFG Shift Feature' of iATU is enabled. Signed-off-by: Krishna Chaitanya Chundru <krishna.chundru@oss.qualcomm.com> [mani: code split, reworded subject/description and comments] Signed-off-by: Manivannan Sadhasivam <mani@kernel.org> Link: https://patch.msgid.link/20250923-controller-dwc-ecam-v10-3-e84390ba75fa@kernel.org
2025-09-25PCI: dwc: Prepare the driver for enabling ECAM mechanism using iATU 'CFG ↵Krishna Chaitanya Chundru
Shift Feature' In order to enable PCIe ECAM mechanism in DWC driver as per the 'CFG Shift Feature' documented in Designware databook r5.20a, sec 3.10.10.3, prepare the driver to handle the one time iATU setup and creating ECAM window. Signed-off-by: Krishna Chaitanya Chundru <krishna.chundru@oss.qualcomm.com> [mani: splitted the preparatory code into a separate commit for bisectability] Signed-off-by: Manivannan Sadhasivam <mani@kernel.org> Link: https://patch.msgid.link/20250923-controller-dwc-ecam-v10-2-e84390ba75fa@kernel.org
2025-09-25PCI: dwc: Add support for ELBI resource mappingKrishna Chaitanya Chundru
External Local Bus Interface (ELBI) is an optional register space for all DWC IPs containing the vendor specific registers. There is no need for the vendor glue drivers to fetch and map the ELBI region separately. Hence, optionally fetch and map the resource from DT in the DWC core. This also warrants dropping the corresponding code from glue drivers. Hence, drop the ELBI resource fetch and map logic from glue drivers and convert them to use 'dw_pci::elbi_base'. Note that the pcie-qcom-ep driver used devm_pci_remap_cfg_resource() to map the ELBI resource previously. But it was a mistake since devm_pci_remap_cfg_resource() should only be used for mapping the PCIe config space region as it maps the region as Non-Posted. As ELBI is used to hold vendor specific registers, there is no need to map the region as Non-Posted. With this conversion, the region will get mapped as normal MMIO memory. Suggested-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org> Signed-off-by: Krishna Chaitanya Chundru <krishna.chundru@oss.qualcomm.com> [mani: removed elbi override, converted glue drivers and reworded description] Signed-off-by: Manivannan Sadhasivam <mani@kernel.org> Link: https://patch.msgid.link/20250923-controller-dwc-ecam-v10-1-e84390ba75fa@kernel.org
2025-09-24PCI: Don't print stale information about resourceIlpo Järvinen
pbus_size_mem() logs the bridge window resource using pci_info() before the start and end fields of the resource have been updated which then prints stale information. Set resource addresses earlier to make understanding logs easier. Regrettably, this results in setting the addresses multiple times but that seems unavoidable. Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Link: https://patch.msgid.link/20250924135641.3399-1-ilpo.jarvinen@linux.intel.com
2025-09-24PCI: tegra194: Handle errors in BPMP responseVidya Sagar
The return value from tegra_bpmp_transfer() indicates the success or failure of the IPC transaction with BPMP. If the transaction succeeded, we also need to check the actual command's result code. If we don't have error handling for tegra_bpmp_transfer(), we will set the pcie->ep_state to EP_STATE_ENABLED even when the tegra_bpmp_transfer() command fails. Thus, the pcie->ep_state will get out of sync with reality, and any further PERST# assert + deassert will be a no-op and will not trigger the hardware initialization sequence. This is because pex_ep_event_pex_rst_deassert() checks the current pcie->ep_state, and does nothing if the current state is already EP_STATE_ENABLED. Thus, it is important to have error handling for tegra_bpmp_transfer(), such that the pcie->ep_state can not get out of sync with reality, so that we will try to initialize the hardware not only during the first PERST# assert + deassert, but also during any succeeding PERST# assert + deassert. One example where this fix is needed is when using a rock5b as host. During the initial PERST# assert + deassert (triggered by the bootloader on the rock5b) pex_ep_event_pex_rst_deassert() will get called, but for some unknown reason, the tegra_bpmp_transfer() call to initialize the PHY fails. Once Linux has been loaded on the rock5b, the PCIe driver will once again assert + deassert PERST#. However, without tegra_bpmp_transfer() error handling, this second PERST# assert + deassert will not trigger the hardware initialization sequence. With tegra_bpmp_transfer() error handling, the second PERST# assert + deassert will once again trigger the hardware to be initialized and this time the tegra_bpmp_transfer() succeeds. Fixes: c57247f940e8 ("PCI: tegra: Add support for PCIe endpoint mode in Tegra194") Signed-off-by: Vidya Sagar <vidyas@nvidia.com> [cassel: improve commit log] Signed-off-by: Niklas Cassel <cassel@kernel.org> Signed-off-by: Manivannan Sadhasivam <mani@kernel.org> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Reviewed-by: Jon Hunter <jonathanh@nvidia.com> Acked-by: Thierry Reding <treding@nvidia.com> Cc: stable@vger.kernel.org Link: https://patch.msgid.link/20250922140822.519796-8-cassel@kernel.org
2025-09-24PCI: tegra194: Reset BARs when running in PCIe endpoint modeNiklas Cassel
Tegra already defines all BARs except BAR0 as BAR_RESERVED. This is sufficient for pci-epf-test to not allocate backing memory and to not call set_bar() for those BARs. However, marking a BAR as BAR_RESERVED does not mean that the BAR gets disabled. The host side driver, pci_endpoint_test, simply does an ioremap for all enabled BARs and will run tests against all enabled BARs, so it will run tests against the BARs marked as BAR_RESERVED. After running the BAR tests (which will write to all enabled BARs), the inbound address translation is broken. This is because the tegra controller exposes the ATU Port Logic Structure in BAR4, so when BAR4 is written, the inbound address translation settings get overwritten. To avoid this, implement the dw_pcie_ep_ops .init() callback and start off by disabling all BARs (pci-epf-test will later enable/configure BARs that are not defined as BAR_RESERVED). This matches the behavior of other PCIe endpoint drivers: dra7xx, imx6, layerscape-ep, artpec6, dw-rockchip, qcom-ep, rcar-gen4, and uniphier-ep. With this, the PCI endpoint kselftest test case CONSECUTIVE_BAR_TEST (which was specifically made to detect address translation issues) passes. Fixes: c57247f940e8 ("PCI: tegra: Add support for PCIe endpoint mode in Tegra194") Signed-off-by: Niklas Cassel <cassel@kernel.org> Signed-off-by: Manivannan Sadhasivam <mani@kernel.org> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Cc: stable@vger.kernel.org Link: https://patch.msgid.link/20250922140822.519796-7-cassel@kernel.org
2025-09-24PCI/sysfs: Ensure devices are powered for config readsBrian Norris
The "max_link_width", "current_link_speed", "current_link_width", "secondary_bus_number", and "subordinate_bus_number" sysfs files all access config registers, but they don't check the runtime PM state. If the device is in D3cold or a parent bridge is suspended, we may see -EINVAL, bogus values, or worse, depending on implementation details. Wrap these access in pci_config_pm_runtime_{get,put}() like most of the rest of the similar sysfs attributes. Notably, "max_link_speed" does not access config registers; it returns a cached value since d2bd39c0456b ("PCI: Store all PCIe Supported Link Speeds"). Fixes: 56c1af4606f0 ("PCI: Add sysfs max_link_speed/width, current_link_speed/width, etc") Signed-off-by: Brian Norris <briannorris@google.com> Signed-off-by: Brian Norris <briannorris@chromium.org> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Cc: stable@vger.kernel.org Link: https://patch.msgid.link/20250924095711.v2.1.Ibb5b6ca1e2c059e04ec53140cd98a44f2684c668@changeid
2025-09-24PCI: tegra194: Set pci_epc_features::msi_capable to trueNiklas Cassel
Since the driver supports MSI, set the flag to true. This helps pci_endpoint_test to use the optimal IRQ type when using PCITEST_IRQ_TYPE_AUTO. Signed-off-by: Niklas Cassel <cassel@kernel.org> [mani: splitted this change from the bug fix] Signed-off-by: Manivannan Sadhasivam <mani@kernel.org> Link: https://patch.msgid.link/20250922140822.519796-6-cassel@kernel.org
2025-09-24PCI: tegra194: Fix broken tegra_pcie_ep_raise_msi_irq()Niklas Cassel
The pci_epc_raise_irq() supplies a MSI or MSI-X interrupt number in range (1-N), as per the pci_epc_raise_irq() kdoc, where N is 32 for MSI. But tegra_pcie_ep_raise_msi_irq() incorrectly uses the interrupt number as the MSI vector. This causes wrong MSI vector to be triggered, leading to the failure of PCI endpoint Kselftest MSI_TEST test case. To fix this issue, convert the interrupt number to MSI vector. Fixes: c57247f940e8 ("PCI: tegra: Add support for PCIe endpoint mode in Tegra194") Signed-off-by: Niklas Cassel <cassel@kernel.org> Signed-off-by: Manivannan Sadhasivam <mani@kernel.org> Cc: stable@vger.kernel.org Link: https://patch.msgid.link/20250922140822.519796-6-cassel@kernel.org
2025-09-23PCI: qcom: Remove custom ASPM enablement codeManivannan Sadhasivam
Since the PCI subsystem has started enabling all ASPM states for all devicetree based platforms, the ASPM enablement code from this driver can now be dropped. Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@oss.qualcomm.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Link: https://patch.msgid.link/20250922-pci-dt-aspm-v2-2-2a65cf84e326@oss.qualcomm.com
2025-09-23PCI/ASPM: Enable all ClockPM and ASPM states for devicetree platformsManivannan Sadhasivam
So far, the PCI subsystem has honored the ASPM and Clock PM states set by the BIOS (through LNKCTL) during device initialization, if it relies on the default state selected using: * Kconfig: CONFIG_PCIEASPM_DEFAULT=y, or * cmdline: "pcie_aspm=off", or * FADT: ACPI_FADT_NO_ASPM This was done conservatively to avoid issues with the buggy devices that advertise ASPM capabilities, but behave erratically if the ASPM states are enabled. So the PCI subsystem ended up trusting the BIOS to enable only the ASPM states that were known to work for the devices. But this turned out to be a problem for devicetree platforms, especially the ARM based devicetree platforms powering Embedded and *some* Compute devices as they tend to run without any standard BIOS. So the ASPM states on these platforms were left disabled during boot and the PCI subsystem never bothered to enable them, unless the user has forcefully enabled the ASPM states through Kconfig, cmdline, and sysfs or the device drivers themselves, enabling the ASPM states through pci_enable_link_state() APIs. This caused runtime power issues on those platforms. So a couple of approaches were tried to mitigate this BIOS dependency without user intervention by enabling the ASPM states in the PCI controller drivers after device enumeration, and overriding the ASPM/Clock PM states by the PCI controller drivers through an API before enumeration. But it has been concluded that none of these mitigations should really be required and the PCI subsystem should enable the ASPM states advertised by the devices without relying on BIOS or the PCI controller drivers. If any device is found to be misbehaving after enabling ASPM states that they advertised, then those devices should be quirked to disable the problematic ASPM/Clock PM states. In an effort to do so, start by overriding the ASPM and Clock PM states set by the BIOS for devicetree platforms first. Separate helper functions are introduced to override the BIOS set states by enabling all of them if of_have_populated_dt() returns true. To aid debugging, print the overridden ASPM and Clock PM states as well. In the future, these helpers could be extended to allow other platforms like VMD, newer ACPI systems with a cutoff year etc... to follow the path. Link: https://lore.kernel.org/linux-pci/20250828204345.GA958461@bhelgaas Suggested-by: Bjorn Helgaas <helgaas@kernel.org> Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@oss.qualcomm.com> [bhelgaas: tweak comments and dmesg logs] Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Link: https://patch.msgid.link/20250922-pci-dt-aspm-v2-1-2a65cf84e326@oss.qualcomm.com
2025-09-22PCI/PM: Skip resuming to D0 if device is disconnectedMario Limonciello
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
2025-09-22PCI: tegra194: Fix duplicate PLL disable in pex_ep_event_pex_rst_assert()Nagarjuna Kristam
During PERST# assertion tegra_pcie_bpmp_set_pll_state() is currently called twice. pex_ep_event_pex_rst_assert() should do the opposite of pex_ep_event_pex_rst_deassert(), so it is obvious that the duplicate tegra_pcie_bpmp_set_pll_state() is a mistake, and that the duplicate tegra_pcie_bpmp_set_pll_state() call should instead be a call to tegra_pcie_bpmp_set_ctrl_state(). With this, the uninitialization sequence also matches that of tegra_pcie_unconfig_controller(). Fixes: a54e19073718 ("PCI: tegra194: Add Tegra234 PCIe support") Signed-off-by: Nagarjuna Kristam <nkristam@nvidia.com> [cassel: improve commit log] Signed-off-by: Niklas Cassel <cassel@kernel.org> Link: https://patch.msgid.link/20250911093021.1454385-2-cassel@kernel.org [mani: added Fixes tag] Signed-off-by: Manivannan Sadhasivam <mani@kernel.org>
2025-09-19PCI: sg2042: Add Sophgo SG2042 PCIe driverChen Wang
Add support for PCIe controller in Sophgo SG2042 SoC. The controller uses the Cadence PCIe core programmed by pcie-cadence* common driver. The PCIe controller in SG2042 works in host mode only, supporting data rate up to 16 GT/s and lanes up to x16 or x8. Signed-off-by: Chen Wang <unicorn_wang@outlook.com> [mani: reworded description and minor code cleanups] Signed-off-by: Manivannan Sadhasivam <mani@kernel.org> Link: https://patch.msgid.link/01b0a57cd9dba8bed7c1f2d52997046c2c6f042b.1757643388.git.unicorn_wang@outlook.com
2025-09-19PCI: cadence: Check for the existence of cdns_pcie::ops before using itChen Wang
cdns_pcie::ops might not be populated by all the Cadence glue drivers. This is going to be true for the upcoming Sophgo platform which doesn't set the ops. Hence, add a check to prevent NULL pointer dereference. Signed-off-by: Chen Wang <unicorn_wang@outlook.com> [mani: reworded subject and description] Signed-off-by: Manivannan Sadhasivam <mani@kernel.org> Link: https://patch.msgid.link/35182ee1d972dfcd093a964e11205efcebbdc044.1757643388.git.unicorn_wang@outlook.com
2025-09-17PCI/sysfs: Expose PCI device serial numberMatthew Wood
Add a single sysfs read-only interface for reading PCI device serial numbers from userspace in a programmatic way. This device attribute uses the same hexadecimal 1-byte dashed formatting as lspci serial number capability output. If a device doesn't support the serial number capability, the serial_number sysfs attribute will not be visible. Signed-off-by: Matthew Wood <thepacketgeek@gmail.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Reviewed-by: Mario Limonciello <superm1@kernel.org> Reviewed-by: Jonathan Cameron <jonathan.cameron@huawei.com> Reviewed-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de> Reviewed-by: Keith Busch <kbusch@kernel.org> Reviewed-by: Krzysztof Wilczyński <kwilczynski@kernel.org> Link: https://patch.msgid.link/20250917125815.722952-2-thepacketgeek@gmail.com
2025-09-17PCI: qcom: Move host bridge 'phy' and 'reset' pointers to struct qcom_pcie_portManivannan Sadhasivam
DT binding allows specifying 'phy' and 'reset' properties in both host bridge and Root Port nodes, though specifying in the host bridge node is marked as deprecated. Still, the pcie-qcom driver should support both combinations for maintaining the DT backwards compatibility. For this purpose, the driver is holding the relevant pointers of these properties in two structs: struct qcom_pcie_port and struct qcom_pcie. However, this causes confusion and increases the driver complexity. Hence, move the pointers from struct qcom_pcie to struct qcom_pcie_port. As a result, even if these properties are specified in the host bridge node, the pointers will be stored in struct qcom_pcie_port as if the properties are specified in a single Root Port node. This logic simplifies the driver a lot. Suggested-by: Bjorn Helgaas <helgaas@kernel.org> Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@oss.qualcomm.com> Reviewed-by: Bjorn Helgaas <bhelgaas@google.com> Link: https://patch.msgid.link/20250912-pci-pwrctrl-perst-v3-2-3c0ac62b032c@oss.qualcomm.com
2025-09-16PCI: Alter misleading recursion to pci_bus_release_bridge_resources()Ilpo Järvinen
Recursing into pci_bus_release_bridge_resources() should not alter rel_type because it makes no sense to change the release type within the recursion call chain. A literal "whole_subtree" is passed into the recursion instead of "rel_type" parameter which is misleading as the release type should remain the same throughout the entire operation. This is not a correctness issue because of the preceding if () that only allows the recursion to happen if rel_type is "whole_subtree". Still, replace the non-intuitive parameter with direct passing of "rel_type". Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Link: https://patch.msgid.link/20250829131113.36754-25-ilpo.jarvinen@linux.intel.com
2025-09-16PCI: Pass bridge window to pci_bus_release_bridge_resources()Ilpo Järvinen
pci_bus_release_bridge_resources() takes type, which is converted into a bridge window resource in pci_bridge_release_resources(). Find out the correct bridge window for resource whose assignment failed. Pass that bridge window to pci_bus_release_bridge_resources() instead of passing the type. When recursing to subordinate, check which bridge windows have to be released and recurse for each. For now, use pbus_select_window_for_type() instead of pbus_select_window() because non-bridge window resources still have their flags reset which destroys the type information from the struct resource. The struct pci_dev_resource holds a copy of the flags which are used instead. Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Link: https://patch.msgid.link/20250829131113.36754-24-ilpo.jarvinen@linux.intel.com
2025-09-16PCI: Add pci_setup_one_bridge_window()Ilpo Järvinen
pci_bridge_release_resources() contains a resource type hack to work around the unsuitable __pci_setup_bridge() interface. Extract the switch statement that picks the correct bridge window setup function from pci_claim_bridge_resource() into pci_setup_one_bridge_window() and use it also in pci_bridge_release_resources(). Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Link: https://patch.msgid.link/20250829131113.36754-23-ilpo.jarvinen@linux.intel.com
2025-09-16PCI: Refactor remove_dev_resources() to use pbus_select_window()Ilpo Järvinen
Convert remove_dev_resources() to use pbus_select_window(). As 'available' is not the real resources, the index has to be adjusted as only bridge resource counterparts are present in the 'available' array. Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Link: https://patch.msgid.link/20250829131113.36754-22-ilpo.jarvinen@linux.intel.com
2025-09-16PCI: Refactor distributing available memory to use loopsIlpo Järvinen
pci_bus_distribute_available_resources() and pci_bridge_distribute_available_resources() retain bridge window resources and related data needed for distributing the available window in independent variables for io, memory, and prefetchable memory windows. The code is essentially the same for all of them and therefore repeated three times with different variable names. Refactor pci_bus_distribute_available_resources() to take an array. This is complicated slightly by the function taking advantage of passing the struct as value, which cannot be done for arrays in C. Therefore, copy the data into a local array in the stack in the first loop. Variable names are (hopefully) improved slightly as well. Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Link: https://patch.msgid.link/20250829131113.36754-21-ilpo.jarvinen@linux.intel.com
2025-09-16PCI: Use pbus_select_window_for_type() during mem window sizingIlpo Järvinen
__pci_bus_size_bridges() goes to great lengths of helping pbus_size_mem() in which types it should put into a particular bridge window, requiring passing up to three resource type into pbus_size_mem(). Instead of having complex logic in __pci_bus_size_bridges() and a non-straightforward interface between those functions, use pbus_select_window_for_type() and pbus_select_window() to find the correct bridge window and compare if the resources belong to that window. Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Link: https://patch.msgid.link/20250829131113.36754-20-ilpo.jarvinen@linux.intel.com
2025-09-16PCI: Use pbus_select_window() in space available checkerIlpo Järvinen
pbus_upstream_space_available() figures out the upstream bridge window resources on its own. Migrate it to use pbus_select_window(). Note: pbus_select_window() -> pbus_select_window_for_type() calls find_bus_resource_of_type() for root bus, which does not do parent check similar to what pbus_upstream_space_available() did earlier, but the difference does not matter because pbus_upstream_space_available() itself stops when it encounters the root bus. Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Link: https://patch.msgid.link/20250829131113.36754-19-ilpo.jarvinen@linux.intel.com
2025-09-16PCI: Rename resource variable from r to resIlpo Järvinen
Resource is going to be passed in as argument aften an upcoming change. Rename the struct resource variable from "r" to "res" to avoid using one letter variable name in a function argument. This rename is made separately to reduce churn in the upcoming change. Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Link: https://patch.msgid.link/20250829131113.36754-18-ilpo.jarvinen@linux.intel.com
2025-09-16PCI: Use pbus_select_window_for_type() during IO window sizingIlpo Järvinen
Convert pbus_size_io() to use pbus_select_window_for_type(). Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Link: https://patch.msgid.link/20250829131113.36754-17-ilpo.jarvinen@linux.intel.com
2025-09-16PCI: Use pbus_select_window() during BAR resizeIlpo Järvinen
Prior to a BAR resize, __resource_resize_store() loops through the normal resources of the PCI device and releases those that match to the flags of the BAR to be resized. This is necessary to allow resizing also the upstream bridge window as only childless bridge windows can be resized. While the flags check (mostly) works (if corner cases are ignored), the more straightforward way is to check if the resources share the bridge window. Change __resource_resize_store() to do the check using pbus_select_window(). Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Link: https://patch.msgid.link/20250829131113.36754-16-ilpo.jarvinen@linux.intel.com
2025-09-16PCI: Warn if bridge window cannot be released when resizing BARIlpo Järvinen
BAR resizing calls to pci_reassign_bridge_resources(), which attempts to release any upstream bridge window to allow them to accommodate the new BAR size. The release can only be performed if there are no other child resources for the bridge window. Previously the code continued silently when other child resources were detected. Add pci_warn() to inform user that a bridge window could not be released because of child resources. As a small bridge window is often the reason why BAR resize fails, this warning will help to pinpoint to the cause. Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Link: https://patch.msgid.link/20250829131113.36754-15-ilpo.jarvinen@linux.intel.com
2025-09-16PCI: Fix finding bridge window in pci_reassign_bridge_resources()Ilpo Järvinen
pci_reassign_bridge_resources() walks upwards in the PCI bus hierarchy, locates the relevant bridge window on each level using flags check, and attempts to release the bridge window. The flags-based check is fragile due to various fallbacks in the bridge window selection logic. As such, the algorithm might not locate the correct bridge window. Refactor pci_reassign_bridge_resources() to determine the correct bridge window using pbus_select_window(), which contains logic to handle all fallback cases correctly. Change function prefix to pbus as it now inputs struct bus and resource for which to locate the bridge window. The main purpose is to make bridge window selection logic consistent across the entire PCI core (one step at a time). While this technically also fixes the commit 8bb705e3e79d ("PCI: Add pci_resize_resource() for resizing BARs") making the bridge window walk algorithm more robust, the normal setup having a 64-bit resizable BAR underneath bridge(s) with 64-bit prefetchable windows does not need to use any fallbacks. As such, the practical impact is low (requiring BAR resize use case and a non-typical bridge device). The way to detect if unrelated resource failed again is left to use the type based approximation which should not behave worse than before. Fixes: 8bb705e3e79d ("PCI: Add pci_resize_resource() for resizing BARs") Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Link: https://patch.msgid.link/20250829131113.36754-14-ilpo.jarvinen@linux.intel.com
2025-09-16PCI: Add bridge window selection functionsIlpo Järvinen
Various places in the PCI core code independently decide into which bridge window a child resource should be placed. It is hard to see whether these decisions always end up in agreement, especially in the corner cases, and in some places it requires complex logic to pass multiple resource types and/or bridge windows around. Add pbus_select_window() and pbus_select_window_for_type() for cases where the former cannot be used so that eventually the same helper can be used to select the bridge window everywhere. Using the same function ensures the selected bridge window remains always the same and it can be easily recalculated in-situ allowing simplifying the interfaces between internal functions in upcoming changes. Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Link: https://patch.msgid.link/20250829131113.36754-13-ilpo.jarvinen@linux.intel.com
2025-09-16PCI: Add defines for bridge window indexingIlpo Järvinen
include/linux/pci.h provides PCI_BRIDGE_{IO,MEM,PREF_MEM}_WINDOW defines, however, they're based on the resource array indexing in the pci_dev struct. The struct pci_bus also has pointers to those same resources but they start from zeroth index. Add PCI_BUS_BRIDGE_{IO,MEM,PREF_MEM}_WINDOW defines to get rid of literal indexing. Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Link: https://patch.msgid.link/20250829131113.36754-12-ilpo.jarvinen@linux.intel.com
2025-09-16PCI: Preserve bridge window resource type flagsIlpo Järvinen
When a bridge window is found unused or fails to assign, the flags of the associated resource are cleared. Clearing flags is problematic as it also removes the type information of the resource which is needed later. Thus, always preserve the bridge window type flags and use IORESOURCE_UNSET and IORESOURCE_DISABLED to indicate the status of the bridge window. Also, when initializing resources, make sure all valid bridge windows do get their type flags set. Change various places that relied on resource flags being cleared to check for IORESOURCE_UNSET and IORESOURCE_DISABLED to allow bridge window resource to retain their type flags. Add pdev_resource_assignable() and pdev_resource_should_fit() helpers to filter out disabled bridge windows during resource fitting; the latter combines more common checks into the helper. When reading the bridge windows from the registers, instead of leaving the resource flags cleared for bridge windows that are not enabled, always set up the flags and set IORESOURCE_UNSET | IORESOURCE_DISABLED as needed. When resource fitting or assignment fails for a bridge window resource, or the bridge window is not needed, mark the resource with IORESOURCE_UNSET or IORESOURCE_DISABLED, respectively. Use dummy zero resource in resource_show() for backwards compatibility as lspci will otherwise misrepresent disabled bridge windows. This change fixes an issue which highlights the importance of keeping the resource type flags intact: At the end of __assign_resources_sorted(), reset_resource() is called, previously clearing the flags. Later, pci_prepare_next_assign_round() attempted to release bridge resources using pci_bus_release_bridge_resources() that calls into pci_bridge_release_resources() that assumes type flags are still present. As type flags were cleared, IORESOURCE_MEM_64 was not set leading to resources under an incorrect bridge window to be released (idx = 1 instead of idx = 2). While the assignments performed later covered this problem so that the wrongly released resources got assigned in the end, it was still causing extra release+assign pairs. There are other reasons why the resource flags should be retained in upcoming changes too. Removing the flag reset for non-bridge window resource is left as future work, in part because it has a much higher regression potential due to pci_enable_resources() that will start to work also for those resources then and due to what endpoint drivers might assume about resources. Despite the Fixes tag, backporting this (at least any time soon) is highly discouraged. The issue fixed is borderline cosmetic as the later assignments normally cover the problem entirely. Also there might be non-obvious dependencies. Fixes: 5b28541552ef ("PCI: Restrict 64-bit prefetchable bridge windows to 64-bit resources") Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Link: https://patch.msgid.link/20250829131113.36754-11-ilpo.jarvinen@linux.intel.com
2025-09-16PCI: Enable bridge even if bridge window fails to assignIlpo Järvinen
A normal PCI bridge has multiple bridge windows and not all of them are always required by devices underneath the bridge. If a Root Port or bridge does not have a device underneath, no bridge windows get assigned. Yet, pci_enable_resources() is set to fail indiscriminantly on any resource assignment failure if the resource is not known to be optional. In practice, the code in pci_enable_resources() is currently largely dormant. The kernel sets resource flags to zero for any unused bridge window and resets flags to zero in case of an resource assignment failure, which short-circuits pci_enable_resources() because of this check: if (!(r->flags & (IORESOURCE_IO | IORESOURCE_MEM))) continue; However, an upcoming change to resource flags will alter how bridge window resource flags behave activating these long dormants checks in pci_enable_resources(). While complex logic could be built to selectively enable a bridge only under some conditions, a few versions of such logic were tried during development of this change and none of them worked satisfactorily. Thus, I just gave up and decided to enable any bridge regardless of the bridge windows as there seems to be no clear benefit from not enabling it, but a major downside as pcieport will not be probed for the bridge if it's not enabled. Therefore, change pci_enable_resources() to not check if bridge window resources remain unassigned. Resource assignment failures are pretty noisy already so there is no need to log that for bridge windows in pci_enable_resources(). Ignoring bridge window failures hopefully prevents an obvious source of regressions when the upcoming change that no longer clears resource flags for bridge windows is enacted. I've hit this problem even during my own testing on multiple occasions so I expect it to be a quite common problem. This can always be revisited later if somebody thinks the enable check for bridges is not strict enough, but expect a mind-boggling number of regressions from such a change. Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Link: https://patch.msgid.link/20250829131113.36754-10-ilpo.jarvinen@linux.intel.com
2025-09-16PCI: Use pci_release_resource() instead of release_resource()Ilpo Järvinen
A few places in setup-bus.c call release_resource() directly and end up duplicating functionality from pci_release_resource() such as parent check, logging, and clearing the resource. Worse yet, the way the resource is cleared is inconsistent between different sites. Convert release_resource() calls into pci_release_resource() to remove code duplication. This will also make the resource start, end, and flags behavior consistent, i.e., start address is cleared, and only IORESOURCE_UNSET is asserted for the resource. While at it, eliminate the unnecessary initialization of idx variable in pci_bridge_release_resources(). Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Link: https://patch.msgid.link/20250829131113.36754-9-ilpo.jarvinen@linux.intel.com
2025-09-16PCI: Disable non-claimed bridge windowIlpo Järvinen
If clipping or claiming the bridge window fails, the bridge window is left in a state that does not match the kernel's view on what the bridge window is. Disable the bridge window by writing the magic disable value into the Base and Limit Registers if clipping or claiming failed. To detect if claiming the resource was successful, add res->parent checks into the bridge setup functions. Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Link: https://patch.msgid.link/20250829131113.36754-8-ilpo.jarvinen@linux.intel.com
2025-09-16PCI: Always claim bridge window before its setupIlpo Järvinen
When the claim of a resource fails for the full range in pci_claim_bridge_resource(), clipping the resource to a smaller size is attempted. If clipping is successful, the new bridge window is programmed and only as the last step the code attempts to claim the resource again. The order of the last two steps is slightly illogical and inconsistent with the assignment call chains. If claiming the bridge window after clipping fails, the bridge window that was set up is left in place. Rework the logic such that the bridge window is claimed before calling the relevant bridge setup function. This make the behavior consistent with resource fitting call chains that always assign the bridge window before programming it. If claiming the bridge window fails, the clipped bridge window is no longer set up but pci_claim_bridge_resource() returns without writing the bridge window at all. Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Link: https://patch.msgid.link/20250829131113.36754-7-ilpo.jarvinen@linux.intel.com
2025-09-16PCI: Refactor find_bus_resource_of_type() logic checksIlpo Järvinen
Reorder the logic checks in find_bus_resource_of_type() to simplify them. Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Link: https://patch.msgid.link/20250829131113.36754-6-ilpo.jarvinen@linux.intel.com
2025-09-16PCI: Move find_bus_resource_of_type() earlierIlpo Järvinen
Move find_bus_resource_of_type() earlier in setup-bus.c to be able to call it in upcoming changes. Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Link: https://patch.msgid.link/20250829131113.36754-5-ilpo.jarvinen@linux.intel.com
2025-09-16PCI: Fix failure detection during resource resizeIlpo Järvinen
Since 96336ec70264 ("PCI: Perform reset_resource() and build fail list in sync") the failed list is always built and returned to let the caller decide what to do with the failures. The caller may want to retry resource fitting and assignment and before that can happen, the resources should be restored to their original state (a reset effectively clears the struct resource), which requires returning them to the failed list so the original state remains stored in the associated struct pci_dev_resource. Resource resizing is different from the ordinary resource fitting and assignment in that it only considers part of the resources. This means failures for other resource types are not relevant at all and should be ignored. As resize doesn't unassign such unrelated resources, those resources ending up in the failed list implies assignment of that resource must have failed before resize too. The check in pci_reassign_bridge_resources() to decide if the whole assignment is successful, however, is based on list emptiness which will cause false negatives when the failed list has resources with an unrelated type. If the failed list is not empty, call pci_required_resource_failed() and extend it to be able to filter on specific resource types too (if provided). Calling pci_required_resource_failed() at this point is slightly problematic because the resource itself is reset when the failed list is constructed in __assign_resources_sorted(). As a result, pci_resource_is_optional() does not have access to the original resource flags. This could be worked around by restoring and re-resetting the resource around the call to pci_resource_is_optional(), however, it shouldn't cause issue as resource resizing is meant for 64-bit prefetchable resources according to Christian König (see the Link which unfortunately doesn't point directly to Christian's reply because lore didn't store that email at all). Fixes: 96336ec70264 ("PCI: Perform reset_resource() and build fail list in sync") Link: https://lore.kernel.org/all/c5d1b5d8-8669-5572-75a7-0b480f581ac1@linux.intel.com/ Reported-by: D Scott Phillips <scott@os.amperecomputing.com> Closes: https://lore.kernel.org/all/86plf0lgit.fsf@scott-ph-mail.amperecomputing.com/ Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Tested-by: D Scott Phillips <scott@os.amperecomputing.com> Reviewed-by: D Scott Phillips <scott@os.amperecomputing.com> Cc: Christian König <christian.koenig@amd.com> Cc: stable@vger.kernel.org # v6.15+ Link: https://patch.msgid.link/20250822123359.16305-4-ilpo.jarvinen@linux.intel.com
2025-09-16PCI: Fix pdev_resources_assignable() disparityIlpo Järvinen
pdev_sort_resources() uses pdev_resources_assignable() helper to decide if device's resources cannot be assigned, so it ignores class 0 (PCI_CLASS_NOT_DEFINED) devices. pbus_size_mem(), on the other hand, does not do the same check. This could lead into a situation where a resource ends up on realloc_head list but is not on the head list, which in turn prevents emptying the resource from the realloc_head list in __assign_resources_sorted(). A non-empty realloc_head is unacceptable because it triggers an internal sanity check as shown in this log with a device that has class 0 (PCI_CLASS_NOT_DEFINED): pci 0001:01:00.0: [144d:a5a5] type 00 class 0x000000 PCIe Endpoint pci 0001:01:00.0: BAR 0 [mem 0x00000000-0x000fffff 64bit] pci 0001:01:00.0: ROM [mem 0x00000000-0x0000ffff pref] pcieport 0001:00:00.0: bridge window [mem 0x00100000-0x001fffff] to [bus 01-ff] add_size 100000 add_align 100000 pcieport 0001:00:00.0: bridge window [mem 0x40000000-0x401fffff]: assigned ------------[ cut here ]------------ kernel BUG at drivers/pci/setup-bus.c:2532! Internal error: Oops - BUG: 00000000f2000800 [#1] SMP ... Call trace: pci_assign_unassigned_bus_resources+0x110/0x114 (P) pci_rescan_bus+0x28/0x48 Use pdev_resources_assignable() also within pbus_size_mem() to skip processing of non-assignable resources which removes the disparity in between what resources pdev_sort_resources() and pbus_size_mem() consider. As non-assignable resources are no longer processed, they are not added to the realloc_head list, thus the sanity check no longer triggers. This disparity problem is very old but only now became apparent after 2499f5348431 ("PCI: Rework optional resource handling") that made the ROM resources optional when calculating bridge window sizes which required adding the resource to the realloc_head list. Previously, bridge windows were just sized larger than necessary. Fixes: 2499f5348431 ("PCI: Rework optional resource handling") Reported-by: Tudor Ambarus <tudor.ambarus@linaro.org> Closes: https://lore.kernel.org/all/5f103643-5e1c-43c6-b8fe-9617d3b5447c@linaro.org/ Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Cc: stable@vger.kernel.org # v6.15+ Link: https://patch.msgid.link/20250822123359.16305-3-ilpo.jarvinen@linux.intel.com
2025-09-16PCI: Ensure relaxed tail alignment does not increase min_alignIlpo Järvinen
When using relaxed tail alignment for the bridge window, pbus_size_mem() also tries to minimize min_align, which can under certain scenarios end up increasing min_align from that found by calculate_mem_align(). Ensure min_align is not increased by the relaxed tail alignment. Eventually, it would be better to add calculate_relaxed_head_align() similar to calculate_mem_align() which finds out what alignment can be used for the head without introducing any gaps into the bridge window to give flexibility on head address too. But that looks relatively complex so it requires much more testing than fixing the immediate problem causing a regression. Fixes: 67f9085596ee ("PCI: Allow relaxed bridge window tail sizing for optional resources") Reported-by: Rio Liu <rio@r26.me> Closes: https://lore.kernel.org/all/o2bL8MtD_40-lf8GlslTw-AZpUPzm8nmfCnJKvS8RQ3NOzOW1uq1dVCEfRpUjJ2i7G2WjfQhk2IWZ7oGp-7G-jXN4qOdtnyOcjRR0PZWK5I=@r26.me/ Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Tested-by: Rio Liu <rio@r26.me> Cc: stable@vger.kernel.org # v6.15+ Link: https://patch.msgid.link/20250822123359.16305-2-ilpo.jarvinen@linux.intel.com
2025-09-16PCI: endpoint: pci-epf-test: Add NULL check for DMA channels before releaseShin'ichiro Kawasaki
The fields dma_chan_tx and dma_chan_rx of the struct pci_epf_test can be NULL even after EPF initialization. Then it is prudent to check that they have non-NULL values before releasing the channels. Add the checks in pci_epf_test_clean_dma_chan(). Without the checks, NULL pointer dereferences happen and they can lead to a kernel panic in some cases: Unable to handle kernel NULL pointer dereference at virtual address 0000000000000050 Call trace: dma_release_channel+0x2c/0x120 (P) pci_epf_test_epc_deinit+0x94/0xc0 [pci_epf_test] pci_epc_deinit_notify+0x74/0xc0 tegra_pcie_ep_pex_rst_irq+0x250/0x5d8 irq_thread_fn+0x34/0xb8 irq_thread+0x18c/0x2e8 kthread+0x14c/0x210 ret_from_fork+0x10/0x20 Fixes: 8353813c88ef ("PCI: endpoint: Enable DMA tests for endpoints with DMA capabilities") Fixes: 5ebf3fc59bd2 ("PCI: endpoint: functions/pci-epf-test: Add DMA support to transfer data") Signed-off-by: Shin'ichiro Kawasaki <shinichiro.kawasaki@wdc.com> [mani: trimmed the stack trace] Signed-off-by: Manivannan Sadhasivam <mani@kernel.org> Reviewed-by: Damien Le Moal <dlemoal@kernel.org> Reviewed-by: Krzysztof Wilczyński <kwilczynski@kernel.org> Cc: stable@vger.kernel.org Link: https://patch.msgid.link/20250916025756.34807-1-shinichiro.kawasaki@wdc.com