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/md/persistent-data/dm-space-map.h | 169 ++++++++++++++++++++++++++++++ 1 file changed, 169 insertions(+) create mode 100644 drivers/md/persistent-data/dm-space-map.h (limited to 'drivers/md/persistent-data/dm-space-map.h') diff --git a/drivers/md/persistent-data/dm-space-map.h b/drivers/md/persistent-data/dm-space-map.h new file mode 100644 index 000000000..6bf69922b --- /dev/null +++ b/drivers/md/persistent-data/dm-space-map.h @@ -0,0 +1,169 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* + * Copyright (C) 2011 Red Hat, Inc. + * + * This file is released under the GPL. + */ + +#ifndef _LINUX_DM_SPACE_MAP_H +#define _LINUX_DM_SPACE_MAP_H + +#include "dm-block-manager.h" + +typedef void (*dm_sm_threshold_fn)(void *context); + +/* + * struct dm_space_map keeps a record of how many times each block in a device + * is referenced. It needs to be fixed on disk as part of the transaction. + */ +struct dm_space_map { + void (*destroy)(struct dm_space_map *sm); + + /* + * You must commit before allocating the newly added space. + */ + int (*extend)(struct dm_space_map *sm, dm_block_t extra_blocks); + + /* + * Extensions do not appear in this count until after commit has + * been called. + */ + int (*get_nr_blocks)(struct dm_space_map *sm, dm_block_t *count); + + /* + * Space maps must never allocate a block from the previous + * transaction, in case we need to rollback. This complicates the + * semantics of get_nr_free(), it should return the number of blocks + * that are available for allocation _now_. For instance you may + * have blocks with a zero reference count that will not be + * available for allocation until after the next commit. + */ + int (*get_nr_free)(struct dm_space_map *sm, dm_block_t *count); + + int (*get_count)(struct dm_space_map *sm, dm_block_t b, uint32_t *result); + int (*count_is_more_than_one)(struct dm_space_map *sm, dm_block_t b, + int *result); + int (*set_count)(struct dm_space_map *sm, dm_block_t b, uint32_t count); + + int (*commit)(struct dm_space_map *sm); + + int (*inc_blocks)(struct dm_space_map *sm, dm_block_t b, dm_block_t e); + int (*dec_blocks)(struct dm_space_map *sm, dm_block_t b, dm_block_t e); + + /* + * new_block will increment the returned block. + */ + int (*new_block)(struct dm_space_map *sm, dm_block_t *b); + + /* + * The root contains all the information needed to fix the space map. + * Generally this info is small, so squirrel it away in a disk block + * along with other info. + */ + int (*root_size)(struct dm_space_map *sm, size_t *result); + int (*copy_root)(struct dm_space_map *sm, void *copy_to_here_le, size_t len); + + /* + * You can register one threshold callback which is edge-triggered + * when the free space in the space map drops below the threshold. + */ + int (*register_threshold_callback)(struct dm_space_map *sm, + dm_block_t threshold, + dm_sm_threshold_fn fn, + void *context); +}; + +/*----------------------------------------------------------------*/ + +static inline void dm_sm_destroy(struct dm_space_map *sm) +{ + if (sm) + sm->destroy(sm); +} + +static inline int dm_sm_extend(struct dm_space_map *sm, dm_block_t extra_blocks) +{ + return sm->extend(sm, extra_blocks); +} + +static inline int dm_sm_get_nr_blocks(struct dm_space_map *sm, dm_block_t *count) +{ + return sm->get_nr_blocks(sm, count); +} + +static inline int dm_sm_get_nr_free(struct dm_space_map *sm, dm_block_t *count) +{ + return sm->get_nr_free(sm, count); +} + +static inline int dm_sm_get_count(struct dm_space_map *sm, dm_block_t b, + uint32_t *result) +{ + return sm->get_count(sm, b, result); +} + +static inline int dm_sm_count_is_more_than_one(struct dm_space_map *sm, + dm_block_t b, int *result) +{ + return sm->count_is_more_than_one(sm, b, result); +} + +static inline int dm_sm_set_count(struct dm_space_map *sm, dm_block_t b, + uint32_t count) +{ + return sm->set_count(sm, b, count); +} + +static inline int dm_sm_commit(struct dm_space_map *sm) +{ + return sm->commit(sm); +} + +static inline int dm_sm_inc_blocks(struct dm_space_map *sm, dm_block_t b, dm_block_t e) +{ + return sm->inc_blocks(sm, b, e); +} + +static inline int dm_sm_inc_block(struct dm_space_map *sm, dm_block_t b) +{ + return dm_sm_inc_blocks(sm, b, b + 1); +} + +static inline int dm_sm_dec_blocks(struct dm_space_map *sm, dm_block_t b, dm_block_t e) +{ + return sm->dec_blocks(sm, b, e); +} + +static inline int dm_sm_dec_block(struct dm_space_map *sm, dm_block_t b) +{ + return dm_sm_dec_blocks(sm, b, b + 1); +} + +static inline int dm_sm_new_block(struct dm_space_map *sm, dm_block_t *b) +{ + return sm->new_block(sm, b); +} + +static inline int dm_sm_root_size(struct dm_space_map *sm, size_t *result) +{ + return sm->root_size(sm, result); +} + +static inline int dm_sm_copy_root(struct dm_space_map *sm, void *copy_to_here_le, size_t len) +{ + return sm->copy_root(sm, copy_to_here_le, len); +} + +static inline int dm_sm_register_threshold_callback(struct dm_space_map *sm, + dm_block_t threshold, + dm_sm_threshold_fn fn, + void *context) +{ + if (sm->register_threshold_callback) + return sm->register_threshold_callback(sm, threshold, fn, context); + + return -EINVAL; +} + + +#endif /* _LINUX_DM_SPACE_MAP_H */ -- cgit v1.3.1