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authorLinus Torvalds <torvalds@linux-foundation.org>2026-08-24 08:46:03 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2026-08-24 08:46:03 -0700
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Merge tag 'pinctrl-v7.3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrlgrafted
Pull pin control updates from Linus Walleij: "Core changes: - Use the non-blocking mux_state_try_select() in the generic MUX pin control back-end - Free pin maps on pinctrl_generic_to_map() failure in the core helpers New hardware pin control: - Qualcomm Maili TLMM SoC, PMG1110 PMIC, and Eliza LPASS LPI TLMM SoC (this is for the low power audio, LPASS = Low Power Audio SubSystem portions) - Upboard support on top of the Intel pin controller - Apple T6030 and T6031 support (just compatible strings) - Samsung Exynos 8855 SoC - Mediatek MT6858 SoC - Rockchip RK3308B and RV1106 SoCs - Airoha EN7523 and AN7563 SoCs Improvements: - Qualcomm TLMM GPIOs are unconditionally marked as wakeup capable - Qualcomm improvements on top of the Qualcomm PDC (power domain controller) irqchip improvements from tglx:s tree - Qualcomm IPQ806x and IPQ9650 non-urgent pin grop fixups - The NPCM8xx driver has been put into shape fixing many pin and group definitions - Some non-urgent Tegra 264 pin assignments are fixed up - Some non-urgent fixups to Airoha AN7581 and AN7583 registers and pin assignments, missing features etc" * tag 'pinctrl-v7.3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrl: (130 commits) dt-bindings: pinctrl: Convert TI DA850 pupd to DT schema pinctrl: meson: sync some modify from A4 pinctrl: meson: a4: Add input enable pin configuration pinctrl: realtek: rtd1625: remove unused group name spdif_sel pinctrl: realtek: rtd1625: fix base_bit for VE4 GPIO 13 dt-bindings: pinctrl: microchip,pic32mzda-pinctrl: Convert to DT schema Revert "Merge branch 'ib-rsk7204' into devel" pinctrl: rockchip: Add RV1106 pinctrl support dt-bindings: pinctrl: rockchip: Add RV1106 compatible pinctrl: rockchip: Decode drive strength in the get function pinctrl: fix PINCTRL_GENERIC_MUX not always being selectable pinctrl: airoha: add support of an7563 SoC dt-bindings: pinctrl: airoha: add support of an7563 pin controller pinctrl: airoha: try to find chip scu node by phandle first pinctrl: airoha: add support of en7523 SoC dt-bindings: pinctrl: airoha: add support of en7523 pin controller pinctrl: airoha: an7583: add support for olt pinmux pinctrl: airoha: an7583: add support for pon_alt pinmux pinctrl: airoha: an7583: add support for npu_uart pinmux dt-bindings: pinctrl: airoha: an7583: add missed features ...
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+What: /sys/kernel/debug/cxl/memX/inject_poison
+Date: April, 2023
+KernelVersion: v6.4
+Contact: linux-cxl@vger.kernel.org
+Description:
+ (WO) When a Device Physical Address (DPA) is written to this
+ attribute, the memdev driver sends an inject poison command to
+ the device for the specified address. The DPA must be 64-byte
+ aligned and the length of the injected poison is 64-bytes. If
+ successful, the device returns poison when the address is
+ accessed through the CXL.mem bus. Injecting poison adds the
+ address to the device's Poison List and the error source is set
+ to Injected. In addition, the device adds a poison creation
+ event to its internal Informational Event log, updates the
+ Event Status register, and if configured, interrupts the host.
+ It is not an error to inject poison into an address that
+ already has poison present and no error is returned. If the
+ device returns 'Inject Poison Limit Reached' an -EBUSY error
+ is returned to the user. The inject_poison attribute is only
+ visible for devices supporting the capability.
+
+ TEST-ONLY INTERFACE: This interface is intended for testing
+ and validation purposes only. It is not a data repair mechanism
+ and should never be used on production systems or live data.
+
+ DATA LOSS RISK: For CXL persistent memory (PMEM) devices,
+ poison injection can result in permanent data loss. Injected
+ poison may render data permanently inaccessible even after
+ clearing, as the clear operation writes zeros and does not
+ recover original data.
+
+ SYSTEM STABILITY RISK: For volatile memory, poison injection
+ can cause kernel crashes, system instability, or unpredictable
+ behavior if the poisoned addresses are accessed by running code
+ or critical kernel structures.
+
+What: /sys/kernel/debug/cxl/memX/clear_poison
+Date: April, 2023
+KernelVersion: v6.4
+Contact: linux-cxl@vger.kernel.org
+Description:
+ (WO) When a Device Physical Address (DPA) is written to this
+ attribute, the memdev driver sends a clear poison command to
+ the device for the specified address. Clearing poison removes
+ the address from the device's Poison List and writes 0 (zero)
+ for 64 bytes starting at address. It is not an error to clear
+ poison from an address that does not have poison set. If the
+ device cannot clear poison from the address, -ENXIO is returned.
+ The clear_poison attribute is only visible for devices
+ supporting the capability.
+
+ TEST-ONLY INTERFACE: This interface is intended for testing
+ and validation purposes only. It is not a data repair mechanism
+ and should never be used on production systems or live data.
+
+ CLEAR IS NOT DATA RECOVERY: This operation writes zeros to the
+ specified address range and removes the address from the poison
+ list. It does NOT recover or restore original data that may have
+ been present before poison injection. Any original data at the
+ cleared address is permanently lost and replaced with zeros.
+
+ CLEAR IS NOT A REPAIR MECHANISM: This interface is for testing
+ purposes only and should not be used as a data repair tool.
+ Clearing poison is fundamentally different from data recovery
+ or error correction.
+
+What: /sys/kernel/debug/cxl/regionX/inject_poison
+Date: August, 2025
+Contact: linux-cxl@vger.kernel.org
+Description:
+ (WO) When a Host Physical Address (HPA) is written to this
+ attribute, the region driver translates it to a Device
+ Physical Address (DPA) and identifies the corresponding
+ memdev. It then sends an inject poison command to that memdev
+ at the translated DPA. Refer to the memdev ABI entry at:
+ /sys/kernel/debug/cxl/memX/inject_poison for the detailed
+ behavior. This attribute is only visible if all memdevs
+ participating in the region support both inject and clear
+ poison commands.
+
+ TEST-ONLY INTERFACE: This interface is intended for testing
+ and validation purposes only. It is not a data repair mechanism
+ and should never be used on production systems or live data.
+
+ DATA LOSS RISK: For CXL persistent memory (PMEM) devices,
+ poison injection can result in permanent data loss. Injected
+ poison may render data permanently inaccessible even after
+ clearing, as the clear operation writes zeros and does not
+ recover original data.
+
+ SYSTEM STABILITY RISK: For volatile memory, poison injection
+ can cause kernel crashes, system instability, or unpredictable
+ behavior if the poisoned addresses are accessed by running code
+ or critical kernel structures.
+
+What: /sys/kernel/debug/cxl/regionX/clear_poison
+Date: August, 2025
+Contact: linux-cxl@vger.kernel.org
+Description:
+ (WO) When a Host Physical Address (HPA) is written to this
+ attribute, the region driver translates it to a Device
+ Physical Address (DPA) and identifies the corresponding
+ memdev. It then sends a clear poison command to that memdev
+ at the translated DPA. Refer to the memdev ABI entry at:
+ /sys/kernel/debug/cxl/memX/clear_poison for the detailed
+ behavior. This attribute is only visible if all memdevs
+ participating in the region support both inject and clear
+ poison commands.
+
+ TEST-ONLY INTERFACE: This interface is intended for testing
+ and validation purposes only. It is not a data repair mechanism
+ and should never be used on production systems or live data.
+
+ CLEAR IS NOT DATA RECOVERY: This operation writes zeros to the
+ specified address range and removes the address from the poison
+ list. It does NOT recover or restore original data that may have
+ been present before poison injection. Any original data at the
+ cleared address is permanently lost and replaced with zeros.
+
+ CLEAR IS NOT A REPAIR MECHANISM: This interface is for testing
+ purposes only and should not be used as a data repair tool.
+ Clearing poison is fundamentally different from data recovery
+ or error correction.
+
+What: /sys/kernel/debug/cxl/einj_types
+Date: January, 2024
+KernelVersion: v6.9
+Contact: linux-cxl@vger.kernel.org
+Description:
+ (RO) Prints the CXL protocol error types made available by
+ the platform in the format:
+
+ 0x<error number> <error type>
+
+ The possible error types are (as of ACPI v6.5):
+
+ 0x1000 CXL.cache Protocol Correctable
+ 0x2000 CXL.cache Protocol Uncorrectable non-fatal
+ 0x4000 CXL.cache Protocol Uncorrectable fatal
+ 0x8000 CXL.mem Protocol Correctable
+ 0x10000 CXL.mem Protocol Uncorrectable non-fatal
+ 0x20000 CXL.mem Protocol Uncorrectable fatal
+
+ The <error number> can be written to einj_inject to inject
+ <error type> into a chosen dport.
+
+What: /sys/kernel/debug/cxl/$dport_dev/einj_inject
+Date: January, 2024
+KernelVersion: v6.9
+Contact: linux-cxl@vger.kernel.org
+Description:
+ (WO) Writing an integer to this file injects the corresponding
+ CXL protocol error into $dport_dev ($dport_dev will be a device
+ name from /sys/bus/pci/devices). The integer to type mapping for
+ injection can be found by reading from einj_types. If the dport
+ was enumerated in RCH mode, a CXL 1.1 error is injected, otherwise
+ a CXL 2.0 error is injected.