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-amd-pmf | 13 +++++++++++++ 1 file changed, 13 insertions(+) create mode 100644 Documentation/ABI/testing/sysfs-amd-pmf (limited to 'Documentation/ABI/testing/sysfs-amd-pmf') diff --git a/Documentation/ABI/testing/sysfs-amd-pmf b/Documentation/ABI/testing/sysfs-amd-pmf new file mode 100644 index 000000000..7fc0e1c2b --- /dev/null +++ b/Documentation/ABI/testing/sysfs-amd-pmf @@ -0,0 +1,13 @@ +What: /sys/devices/platform/*/cnqf_enable +Date: September 2022 +Contact: Shyam Sundar S K +Description: Reading this file tells if the AMD Platform Management(PMF) + Cool n Quiet Framework(CnQF) feature is enabled or not. + + This feature is not enabled by default and gets only turned on + if OEM BIOS passes a "flag" to PMF ACPI function (index 11 or 12) + or in case the user writes "on". + + To turn off CnQF user can write "off" to the sysfs node. + Note: Systems that support auto mode will not have this sysfs file + available. -- cgit v1.3.1