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These notifiers were tied to the former KHO finalize and abort events, which are no longer used. Memblock now preserves its `reserve_mem` regions and registers its metadata by calling kho_preserve_phys(), kho_preserve_folio(), and kho_add_subtree() directly within its initialization function. Signed-off-by: Jason Miu --- include/linux/kexec_handover.h | 5 ++-- kernel/kexec_handover.c | 48 +++++++++++++++++++++------------- mm/memblock.c | 45 +++++++------------------------ 3 files changed, 42 insertions(+), 56 deletions(-) diff --git a/include/linux/kexec_handover.h b/include/linux/kexec_handover.h index c8229cb11f4b..9566c90a3501 100644 --- a/include/linux/kexec_handover.h +++ b/include/linux/kexec_handover.h @@ -27,7 +27,7 @@ bool kho_is_enabled(void); int kho_preserve_folio(struct folio *folio); int kho_preserve_phys(phys_addr_t phys, size_t size); struct folio *kho_restore_folio(phys_addr_t phys); -int kho_add_subtree(struct kho_serialization *ser, const char *name, void *fdt); +int kho_add_subtree(const char *name, void *fdt); int kho_retrieve_subtree(const char *name, phys_addr_t *phys); int register_kho_notifier(struct notifier_block *nb); @@ -58,8 +58,7 @@ static inline struct folio *kho_restore_folio(phys_addr_t phys) return NULL; } -static inline int kho_add_subtree(struct kho_serialization *ser, - const char *name, void *fdt) +static inline int kho_add_subtree(const char *name, void *fdt) { return -EOPNOTSUPP; } diff --git a/kernel/kexec_handover.c b/kernel/kexec_handover.c index 34cf0ce4f359..ee4f430dfae0 100644 --- a/kernel/kexec_handover.c +++ b/kernel/kexec_handover.c @@ -640,9 +640,21 @@ static int kho_debugfs_fdt_add(struct list_head *list, struct dentry *dir, return 0; } +struct kho_out { + struct blocking_notifier_head chain_head; + struct dentry *dir; + struct kho_serialization ser; +}; + +static struct kho_out kho_out = { + .chain_head = BLOCKING_NOTIFIER_INIT(kho_out.chain_head), + .ser = { + .fdt_list = LIST_HEAD_INIT(kho_out.ser.fdt_list), + }, +}; + /** * kho_add_subtree - record the physical address of a sub FDT in KHO root tree. - * @ser: serialization control object passed by KHO notifiers. * @name: name of the sub tree. * @fdt: the sub tree blob. * @@ -655,16 +667,29 @@ static int kho_debugfs_fdt_add(struct list_head *list, struct dentry *dir, * * Return: 0 on success, error code on failure */ -int kho_add_subtree(struct kho_serialization *ser, const char *name, void *fdt) +int kho_add_subtree(const char *name, void *fdt) { + struct kho_serialization *ser = &kho_out.ser; int err = 0; + int root_node_offset, subnode_offset; u64 phys = (u64)virt_to_phys(fdt); void *root = page_to_virt(ser->fdt); - err |= fdt_begin_node(root, name); - err |= fdt_property(root, PROP_SUB_FDT, &phys, sizeof(phys)); - err |= fdt_end_node(root); + /* Reload the KHO root FDT to the same buffer */ + err = fdt_open_into(root, root, PAGE_SIZE); + if (err) + return err; + + root_node_offset = fdt_path_offset(fdt, "/"); + if (root_node_offset < 0) + return root_node_offset; + + subnode_offset = fdt_add_subnode(root, root_node_offset, name); + if (subnode_offset < 0) + return subnode_offset; + err = fdt_setprop(root, subnode_offset, + PROP_SUB_FDT, &phys, sizeof(phys)); if (err) return err; @@ -672,19 +697,6 @@ int kho_add_subtree(struct kho_serialization *ser, const char *name, void *fdt) } EXPORT_SYMBOL_GPL(kho_add_subtree); -struct kho_out { - struct blocking_notifier_head chain_head; - struct dentry *dir; - struct kho_serialization ser; -}; - -static struct kho_out kho_out = { - .chain_head = BLOCKING_NOTIFIER_INIT(kho_out.chain_head), - .ser = { - .fdt_list = LIST_HEAD_INIT(kho_out.ser.fdt_list), - }, -}; - int register_kho_notifier(struct notifier_block *nb) { return blocking_notifier_chain_register(&kho_out.chain_head, nb); diff --git a/mm/memblock.c b/mm/memblock.c index 117d963e677c..602a16cb467a 100644 --- a/mm/memblock.c +++ b/mm/memblock.c @@ -2510,39 +2510,6 @@ int reserve_mem_release_by_name(const char *name) #define RESERVE_MEM_KHO_NODE_COMPATIBLE "reserve-mem-v1" static struct page *kho_fdt; -static int reserve_mem_kho_finalize(struct kho_serialization *ser) -{ - int err = 0, i; - - for (i = 0; i < reserved_mem_count; i++) { - struct reserve_mem_table *map = &reserved_mem_table[i]; - - err |= kho_preserve_phys(map->start, map->size); - } - - err |= kho_preserve_folio(page_folio(kho_fdt)); - err |= kho_add_subtree(ser, MEMBLOCK_KHO_FDT, page_to_virt(kho_fdt)); - - return notifier_from_errno(err); -} - -static int reserve_mem_kho_notifier(struct notifier_block *self, - unsigned long cmd, void *v) -{ - switch (cmd) { - case KEXEC_KHO_FINALIZE: - return reserve_mem_kho_finalize((struct kho_serialization *)v); - case KEXEC_KHO_ABORT: - return NOTIFY_DONE; - default: - return NOTIFY_BAD; - } -} - -static struct notifier_block reserve_mem_kho_nb = { - .notifier_call = reserve_mem_kho_notifier, -}; - static int __init prepare_kho_fdt(void) { int err = 0, i; @@ -2583,7 +2550,7 @@ static int __init prepare_kho_fdt(void) static int __init reserve_mem_init(void) { - int err; + int err, i; if (!kho_is_enabled() || !reserved_mem_count) return 0; @@ -2592,7 +2559,15 @@ static int __init reserve_mem_init(void) if (err) return err; - err = register_kho_notifier(&reserve_mem_kho_nb); + for (i = 0; i < reserved_mem_count; i++) { + struct reserve_mem_table *map = &reserved_mem_table[i]; + + err |= kho_preserve_phys(map->start, map->size); + } + + err |= kho_preserve_folio(page_folio(kho_fdt)); + err |= kho_add_subtree(MEMBLOCK_KHO_FDT, page_to_virt(kho_fdt)); + if (err) { put_page(kho_fdt); kho_fdt = NULL; -- 2.51.0.618.g983fd99d29-goog