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-class-rapidio | 59 +++++++++++++++++++++++++++ 1 file changed, 59 insertions(+) create mode 100644 Documentation/ABI/testing/sysfs-class-rapidio (limited to 'Documentation/ABI/testing/sysfs-class-rapidio') diff --git a/Documentation/ABI/testing/sysfs-class-rapidio b/Documentation/ABI/testing/sysfs-class-rapidio new file mode 100644 index 000000000..81e091455 --- /dev/null +++ b/Documentation/ABI/testing/sysfs-class-rapidio @@ -0,0 +1,59 @@ +What: /sys/class/rapidio_port +Description: + On-chip RapidIO controllers and PCIe-to-RapidIO bridges + (referenced as "Master Port" or "mport") are presented in sysfs + as the special class of devices: "rapidio_port". + The /sys/class/rapidio_port subdirectory contains individual + subdirectories named as "rapidioN" where N = mport ID registered + with RapidIO subsystem. + + NOTE: An mport ID is not a RapidIO destination ID assigned to a + given local mport device. + +What: /sys/class/rapidio_port/rapidio/sys_size +Date: Apr, 2014 +KernelVersion: v3.15 +Contact: Matt Porter , + Alexandre Bounine +Description: + (RO) reports RapidIO common transport system size: + + 0 = small (8-bit destination ID, max. 256 devices), + + 1 = large (16-bit destination ID, max. 65536 devices). + +What: /sys/class/rapidio_port/rapidio/port_destid +Date: Apr, 2014 +KernelVersion: v3.15 +Contact: Matt Porter , + Alexandre Bounine +Description: + +(RO) reports RapidIO destination ID assigned to the given +RapidIO mport device. If value 0xFFFFFFFF is returned this means +that no valid destination ID have been assigned to the mport +(yet). Normally, before enumeration/discovery have been executed +only fabric enumerating mports have a valid destination ID +assigned to them using "hdid=..." rapidio module parameter. + +After enumeration or discovery was performed for a given mport device, +the corresponding subdirectory will also contain subdirectories for each +child RapidIO device connected to the mport. + +The example below shows mport device subdirectory with several child RapidIO +devices attached to it:: + + [rio@rapidio ~]$ ls /sys/class/rapidio_port/rapidio0/ -l + total 0 + drwxr-xr-x 3 root root 0 Feb 11 15:10 00:e:0001 + drwxr-xr-x 3 root root 0 Feb 11 15:10 00:e:0004 + drwxr-xr-x 3 root root 0 Feb 11 15:10 00:e:0007 + drwxr-xr-x 3 root root 0 Feb 11 15:10 00:s:0002 + drwxr-xr-x 3 root root 0 Feb 11 15:10 00:s:0003 + drwxr-xr-x 3 root root 0 Feb 11 15:10 00:s:0005 + lrwxrwxrwx 1 root root 0 Feb 11 15:11 device -> ../../../0000:01:00.0 + -r--r--r-- 1 root root 4096 Feb 11 15:11 port_destid + drwxr-xr-x 2 root root 0 Feb 11 15:11 power + lrwxrwxrwx 1 root root 0 Feb 11 15:04 subsystem -> ../../../../../../class/rapidio_port + -r--r--r-- 1 root root 4096 Feb 11 15:11 sys_size + -rw-r--r-- 1 root root 4096 Feb 11 15:04 uevent -- cgit v1.3.1