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-mei | 105 ++++++++++++++++++++++++++++++ 1 file changed, 105 insertions(+) create mode 100644 Documentation/ABI/testing/sysfs-class-mei (limited to 'Documentation/ABI/testing/sysfs-class-mei') diff --git a/Documentation/ABI/testing/sysfs-class-mei b/Documentation/ABI/testing/sysfs-class-mei new file mode 100644 index 000000000..1db36ddf8 --- /dev/null +++ b/Documentation/ABI/testing/sysfs-class-mei @@ -0,0 +1,105 @@ +What: /sys/class/mei/ +Date: May 2014 +KernelVersion: 3.17 +Contact: Tomas Winkler +Description: + The mei/ class sub-directory belongs to mei device class + + +What: /sys/class/mei/mei/ +Date: May 2014 +KernelVersion: 3.17 +Contact: Tomas Winkler +Description: + The /sys/class/mei/meiN directory is created for + each probed mei device + +What: /sys/class/mei/mei/fw_status +Date: Nov 2014 +KernelVersion: 3.19 +Contact: Tomas Winkler +Description: Display fw status registers content + + The ME FW writes its status information into fw status + registers for BIOS and OS to monitor fw health. + + The register contains running state, power management + state, error codes, and others. The way the registers + are decoded depends on PCH or SoC generation. + Also number of registers varies between 1 and 6 + depending on generation. + +What: /sys/class/mei/mei/hbm_ver +Date: Aug 2016 +KernelVersion: 4.9 +Contact: Tomas Winkler +Description: Display the negotiated HBM protocol version. + + The HBM protocol version negotiated + between the driver and the device. + +What: /sys/class/mei/mei/hbm_ver_drv +Date: Aug 2016 +KernelVersion: 4.9 +Contact: Tomas Winkler +Description: Display the driver HBM protocol version. + + The HBM protocol version supported by the driver. + +What: /sys/class/mei/mei/tx_queue_limit +Date: Jan 2018 +KernelVersion: 4.16 +Contact: Tomas Winkler +Description: Configure tx queue limit + + Set maximal number of pending writes + per opened session. + +What: /sys/class/mei/mei/fw_ver +Date: May 2018 +KernelVersion: 4.18 +Contact: Tomas Winkler +Description: Display the ME firmware version. + + The version of the platform ME firmware is in format: + :.... + There can be up to three such blocks for different + FW components. + +What: /sys/class/mei/mei/dev_state +Date: Mar 2019 +KernelVersion: 5.1 +Contact: Tomas Winkler +Description: Display the ME device state. + + The device state can have following values: + INITIALIZING + INIT_CLIENTS + ENABLED + RESETTING + DISABLED + POWER_DOWN + POWER_UP + +What: /sys/class/mei/mei/trc +Date: Nov 2019 +KernelVersion: 5.5 +Contact: Tomas Winkler +Description: Display trc status register content + + The ME FW writes Glitch Detection HW (TRC) + status information into trc status register + for BIOS and OS to monitor fw health. + +What: /sys/class/mei/mei/kind +Date: Jul 2020 +KernelVersion: 5.8 +Contact: Tomas Winkler +Description: Display kind of the device + + Generic devices are marked as "mei" + while special purpose have their own + names. + Available options: + - mei: generic mei device. + - itouch: itouch (ipts) mei device. -- cgit v1.3.1