From 27600805e62f800bacf990354632eae4e487d34c Mon Sep 17 00:00:00 2001 From: Yazen Ghannam Date: Thu, 3 Sep 2026 10:43:25 -0500 Subject: x86/amd_node: Fix PCI device reference counting in amd_smn_init() The local "root" pointer is a temporary variable used during the device search. Therefore, refcount related to the search iterators should be cleaned up after the search is complete. Use the __free() cleanup macro to ensure the refcount is decremented when the temporary pointer goes out of scope. Additionally, increment the refcount when caching a root pointer. This ensures the in-use refcount is separate from the temporary search refcounting. Finally, drop the redundant "root = NULL" before the second search loop. The pci_get_class() iterator always decrements the refcount of its "from" argument, so the first loop can only fall through with "root" already NULL. Fixes: 0a4b61d9c2e4 ("x86/amd_node: Fix AMD root device caching") Closes: https://sashiko.dev/#/patchset/20260806160159.230453-1-jason.andryuk%40amd.com Reported-by: Sashiko Assisted-by: LLM Signed-off-by: Yazen Ghannam Signed-off-by: Borislav Petkov (AMD) Reviewed-by: Mario Limonciello (AMD) Cc: Link: https://patch.msgid.link/20260903154325.74343-1-yazen.ghannam@amd.com --- Documentation/ABI/testing/sysfs-driver-ppi | 75 ++++++++++++++++++++++++++++++ 1 file changed, 75 insertions(+) create mode 100644 Documentation/ABI/testing/sysfs-driver-ppi (limited to 'Documentation/ABI/testing/sysfs-driver-ppi') diff --git a/Documentation/ABI/testing/sysfs-driver-ppi b/Documentation/ABI/testing/sysfs-driver-ppi new file mode 100644 index 000000000..1a56fc507 --- /dev/null +++ b/Documentation/ABI/testing/sysfs-driver-ppi @@ -0,0 +1,75 @@ +What: /sys/class/tpm/tpmX/ppi/ +Date: August 2012 +KernelVersion: 3.6 +Contact: xiaoyan.zhang@intel.com +Description: + This folder includes the attributes related with PPI (Physical + Presence Interface). Only if TPM is supported by BIOS, this + folder makes sense. The folder path can be got by command + 'find /sys/ -name 'pcrs''. For the detail information of PPI, + please refer to the PPI specification from + + http://www.trustedcomputinggroup.org/ + + In Linux 4.2 ppi was moved to the character device directory. + A symlink from tpmX/device/ppi to tpmX/ppi to provide backwards + compatibility. + +What: /sys/class/tpm/tpmX/ppi/version +Date: August 2012 +Contact: xiaoyan.zhang@intel.com +Description: + This attribute shows the version of the PPI supported by the + platform. + This file is readonly. + +What: /sys/class/tpm/tpmX/ppi/request +Date: August 2012 +Contact: xiaoyan.zhang@intel.com +Description: + This attribute shows the request for an operation to be + executed in the pre-OS environment. It is the only input from + the OS to the pre-OS environment. The request should be an + integer value range from 1 to 160, and 0 means no request. + This file can be read and written. + +What: /sys/class/tpm/tpmX/ppi/response +Date: August 2012 +Contact: xiaoyan.zhang@intel.com +Description: + This attribute shows the response to the most recent operation + request it acted upon. The format is " + : ". + This file is readonly. + +What: /sys/class/tpm/tpmX/ppi/transition_action +Date: August 2012 +Contact: xiaoyan.zhang@intel.com +Description: + This attribute shows the platform-specific action that should + take place in order to transition to the BIOS for execution of + a requested operation. The format is ": ". + This file is readonly. + +What: /sys/class/tpm/tpmX/ppi/tcg_operations +Date: August 2012 +Contact: xiaoyan.zhang@intel.com +Description: + This attribute shows whether it is allowed to request an + operation to be executed in the pre-OS environment by the BIOS + for the requests defined by TCG, i.e. requests from 1 to 22. + The format is " : ". + This attribute is only supported by PPI version 1.2+. + This file is readonly. + +What: /sys/class/tpm/tpmX/ppi/vs_operations +Date: August 2012 +Contact: xiaoyan.zhang@intel.com +Description: + This attribute shows whether it is allowed to request an + operation to be executed in the pre-OS environment by the BIOS + for the verdor specific requests, i.e. requests from 128 to + 255. The format is same with tcg_operations. This attribute + is also only supported by PPI version 1.2+. + This file is readonly. -- cgit v1.3.1