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 --- drivers/dax/bus.h | 81 +++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 81 insertions(+) create mode 100644 drivers/dax/bus.h (limited to 'drivers/dax/bus.h') diff --git a/drivers/dax/bus.h b/drivers/dax/bus.h new file mode 100644 index 000000000..bfc31923f --- /dev/null +++ b/drivers/dax/bus.h @@ -0,0 +1,81 @@ +// SPDX-License-Identifier: GPL-2.0 +/* Copyright(c) 2016 - 2018 Intel Corporation. All rights reserved. */ +#ifndef __DAX_BUS_H__ +#define __DAX_BUS_H__ +#include +#include +#include +#include + +struct dev_dax; +struct resource; +struct dax_device; +struct dax_region; + +/* dax bus specific ioresource flags */ +#define IORESOURCE_DAX_STATIC BIT(0) +#define IORESOURCE_DAX_KMEM BIT(1) + +#define DAX_KMEM_UNPLUGGED (-1) /* Do not create memory blocks */ + +struct dax_region *alloc_dax_region(struct device *parent, int region_id, + struct range *range, int target_node, unsigned int align, + unsigned long flags); + +struct dev_dax_data { + struct dax_region *dax_region; + struct dev_pagemap *pgmap; + resource_size_t size; + int id; + bool memmap_on_memory; +}; + +struct dev_dax *devm_create_dev_dax(struct dev_dax_data *data); + +enum dax_driver_type { + DAXDRV_KMEM_TYPE, + DAXDRV_DEVICE_TYPE, + DAXDRV_FSDEV_TYPE, +}; + +struct dax_device_driver { + struct device_driver drv; + struct list_head ids; + enum dax_driver_type type; + int (*probe)(struct dev_dax *dev); + void (*remove)(struct dev_dax *dev); +}; + +#define to_dax_drv(__drv) container_of_const(__drv, struct dax_device_driver, drv) + +int __dax_driver_register(struct dax_device_driver *dax_drv, + struct module *module, const char *mod_name); +#define dax_driver_register(driver) \ + __dax_driver_register(driver, THIS_MODULE, KBUILD_MODNAME) +void dax_driver_unregister(struct dax_device_driver *dax_drv); +void kill_dev_dax(struct dev_dax *dev_dax); +bool static_dev_dax(struct dev_dax *dev_dax); + +struct hmem_platform_device { + struct platform_device pdev; + struct work_struct work; + bool did_probe; +}; + +static inline struct hmem_platform_device * +to_hmem_platform_device(struct platform_device *pdev) +{ + return container_of(pdev, struct hmem_platform_device, pdev); +} + +#if IS_ENABLED(CONFIG_DEV_DAX_HMEM) +void dax_hmem_flush_work(void); +#else +static inline void dax_hmem_flush_work(void) { } +#endif + +#define MODULE_ALIAS_DAX_DEVICE(type) \ + MODULE_ALIAS("dax:t" __stringify(type) "*") +#define DAX_DEVICE_MODALIAS_FMT "dax:t%d" + +#endif /* __DAX_BUS_H__ */ -- cgit v1.3.1