From cf9610f9116d55c5a66ef9f1faecacabd93a9322 Mon Sep 17 00:00:00 2001 From: Linus Torvalds Date: Mon, 24 Aug 2026 08:46:03 -0700 Subject: Merge tag 'pinctrl-v7.3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrl 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 ... --- Documentation/driver-api/nvdimm/security.rst | 143 +++++++++++++++++++++++++++ 1 file changed, 143 insertions(+) create mode 100644 Documentation/driver-api/nvdimm/security.rst (limited to 'Documentation/driver-api/nvdimm/security.rst') diff --git a/Documentation/driver-api/nvdimm/security.rst b/Documentation/driver-api/nvdimm/security.rst new file mode 100644 index 000000000..eb3d35e6a --- /dev/null +++ b/Documentation/driver-api/nvdimm/security.rst @@ -0,0 +1,143 @@ +=============== +NVDIMM Security +=============== + +1. Introduction +--------------- + +With the introduction of Intel Device Specific Methods (DSM) v1.8 +specification [1], security DSMs are introduced. The spec added the following +security DSMs: "get security state", "set passphrase", "disable passphrase", +"unlock unit", "freeze lock", "secure erase", and "overwrite". A security_ops +data structure has been added to struct dimm in order to support the security +operations and generic APIs are exposed to allow vendor neutral operations. + +2. Sysfs Interface +------------------ +The "security" sysfs attribute is provided in the nvdimm sysfs directory. For +example: +/sys/devices/LNXSYSTM:00/LNXSYBUS:00/ACPI0012:00/ndbus0/nmem0/security + +The "show" attribute of that attribute will display the security state for +that DIMM. The following states are available: disabled, unlocked, locked, +frozen, and overwrite. If security is not supported, the sysfs attribute +will not be visible. + +The "store" attribute takes several commands when it is being written to +in order to support some of the security functionalities: +update - enable or update passphrase. +disable - disable enabled security and remove key. +freeze - freeze changing of security states. +erase - delete existing user encryption key. +overwrite - wipe the entire nvdimm. +master_update - enable or update master passphrase. +master_erase - delete existing user encryption key. + +3. Key Management +----------------- + +The key is associated to the payload by the DIMM id. For example: +# cat /sys/devices/LNXSYSTM:00/LNXSYBUS:00/ACPI0012:00/ndbus0/nmem0/nfit/id +8089-a2-1740-00000133 +The DIMM id would be provided along with the key payload (passphrase) to +the kernel. + +The security keys are managed on the basis of a single key per DIMM. The +key "passphrase" is expected to be 32bytes long. This is similar to the ATA +security specification [2]. A key is initially acquired via the request_key() +kernel API call during nvdimm unlock. It is up to the user to make sure that +all the keys are in the kernel user keyring for unlock. + +A nvdimm encrypted-key of format enc32 has the description format of: +nvdimm: + +See file ``Documentation/security/keys/trusted-encrypted.rst`` for creating +encrypted-keys of enc32 format. TPM usage with a master trusted key is +preferred for sealing the encrypted-keys. + +4. Unlocking +------------ +When the DIMMs are being enumerated by the kernel, the kernel will attempt to +retrieve the key from the kernel user keyring. This is the only time +a locked DIMM can be unlocked. Once unlocked, the DIMM will remain unlocked +until reboot. Typically an entity (i.e. shell script) will inject all the +relevant encrypted-keys into the kernel user keyring during the initramfs phase. +This provides the unlock function access to all the related keys that contain +the passphrase for the respective nvdimms. It is also recommended that the +keys are injected before libnvdimm is loaded by modprobe. + +5. Update +--------- +When doing an update, it is expected that the existing key is removed from +the kernel user keyring and reinjected as different (old) key. It's irrelevant +what the key description is for the old key since we are only interested in the +keyid when doing the update operation. It is also expected that the new key +is injected with the description format described from earlier in this +document. The update command written to the sysfs attribute will be with +the format: +update + +If there is no old keyid due to a security enabling, then a 0 should be +passed in. + +6. Freeze +--------- +The freeze operation does not require any keys. The security config can be +frozen by a user with root privilege. + +7. Disable +---------- +The security disable command format is: +disable + +An key with the current passphrase payload that is tied to the nvdimm should be +in the kernel user keyring. + +8. Secure Erase +--------------- +The command format for doing a secure erase is: +erase + +An key with the current passphrase payload that is tied to the nvdimm should be +in the kernel user keyring. + +9. Overwrite +------------ +The command format for doing an overwrite is: +overwrite + +Overwrite can be done without a key if security is not enabled. A key serial +of 0 can be passed in to indicate no key. + +The sysfs attribute "security" can be polled to wait on overwrite completion. +Overwrite can last tens of minutes or more depending on nvdimm size. + +An encrypted-key with the current user passphrase that is tied to the nvdimm +should be injected and its keyid should be passed in via sysfs. + +10. Master Update +----------------- +The command format for doing a master update is: +update + +The operating mechanism for master update is identical to update except the +master passphrase key is passed to the kernel. The master passphrase key +is just another encrypted-key. + +This command is only available when security is disabled. + +11. Master Erase +---------------- +The command format for doing a master erase is: +master_erase + +This command has the same operating mechanism as erase except the master +passphrase key is passed to the kernel. The master passphrase key is just +another encrypted-key. + +This command is only available when the master security is enabled, indicated +by the extended security status. + +[1]: https://pmem.io/documents/NVDIMM_DSM_Interface-V1.8.pdf + +[2]: http://www.t13.org/documents/UploadedDocuments/docs2006/e05179r4-ACS-SecurityClarifications.pdf -- cgit v1.3.1