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 --- sound/synth/util_mem.c | 175 +++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 175 insertions(+) create mode 100644 sound/synth/util_mem.c (limited to 'sound/synth/util_mem.c') diff --git a/sound/synth/util_mem.c b/sound/synth/util_mem.c new file mode 100644 index 000000000..21893e561 --- /dev/null +++ b/sound/synth/util_mem.c @@ -0,0 +1,175 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Copyright (C) 2000 Takashi Iwai + * + * Generic memory management routines for soundcard memory allocation + */ + +#include +#include +#include +#include +#include +#include + +MODULE_AUTHOR("Takashi Iwai"); +MODULE_DESCRIPTION("Generic memory management routines for soundcard memory allocation"); +MODULE_LICENSE("GPL"); + +#define get_memblk(p) list_entry(p, struct snd_util_memblk, list) + +/* + * create a new memory manager + */ +struct snd_util_memhdr * +snd_util_memhdr_new(int memsize) +{ + struct snd_util_memhdr *hdr; + + hdr = kzalloc_obj(*hdr); + if (hdr == NULL) + return NULL; + hdr->size = memsize; + mutex_init(&hdr->block_mutex); + INIT_LIST_HEAD(&hdr->block); + + return hdr; +} + +/* + * free a memory manager + */ +void snd_util_memhdr_free(struct snd_util_memhdr *hdr) +{ + struct list_head *p; + + if (!hdr) + return; + /* release all blocks */ + while ((p = hdr->block.next) != &hdr->block) { + list_del(p); + kfree(get_memblk(p)); + } + kfree(hdr); +} + +/* + * allocate a memory block (without mutex) + */ +struct snd_util_memblk * +__snd_util_mem_alloc(struct snd_util_memhdr *hdr, int size) +{ + struct snd_util_memblk *blk; + unsigned int units, prev_offset; + struct list_head *p; + + if (snd_BUG_ON(!hdr || size <= 0)) + return NULL; + + /* word alignment */ + units = size; + if (units & 1) + units++; + if (units > hdr->size) + return NULL; + + /* look for empty block */ + prev_offset = 0; + list_for_each(p, &hdr->block) { + blk = get_memblk(p); + if (blk->offset - prev_offset >= units) + goto __found; + prev_offset = blk->offset + blk->size; + } + if (hdr->size - prev_offset < units) + return NULL; + +__found: + return __snd_util_memblk_new(hdr, units, p->prev); +} + + +/* + * create a new memory block with the given size + * the block is linked next to prev + */ +struct snd_util_memblk * +__snd_util_memblk_new(struct snd_util_memhdr *hdr, unsigned int units, + struct list_head *prev) +{ + struct snd_util_memblk *blk; + + blk = kmalloc(sizeof(struct snd_util_memblk) + hdr->block_extra_size, + GFP_KERNEL); + if (blk == NULL) + return NULL; + + if (prev == &hdr->block) + blk->offset = 0; + else { + struct snd_util_memblk *p = get_memblk(prev); + blk->offset = p->offset + p->size; + } + blk->size = units; + list_add(&blk->list, prev); + hdr->nblocks++; + hdr->used += units; + return blk; +} + + +/* + * allocate a memory block (with mutex) + */ +struct snd_util_memblk * +snd_util_mem_alloc(struct snd_util_memhdr *hdr, int size) +{ + guard(mutex)(&hdr->block_mutex); + return __snd_util_mem_alloc(hdr, size); +} + + +/* + * remove the block from linked-list and free resource + * (without mutex) + */ +void +__snd_util_mem_free(struct snd_util_memhdr *hdr, struct snd_util_memblk *blk) +{ + list_del(&blk->list); + hdr->nblocks--; + hdr->used -= blk->size; + kfree(blk); +} + +/* + * free a memory block (with mutex) + */ +int snd_util_mem_free(struct snd_util_memhdr *hdr, struct snd_util_memblk *blk) +{ + if (snd_BUG_ON(!hdr || !blk)) + return -EINVAL; + + guard(mutex)(&hdr->block_mutex); + __snd_util_mem_free(hdr, blk); + return 0; +} + +/* + * return available memory size + */ +int snd_util_mem_avail(struct snd_util_memhdr *hdr) +{ + guard(mutex)(&hdr->block_mutex); + return hdr->size - hdr->used; +} + + +EXPORT_SYMBOL(snd_util_memhdr_new); +EXPORT_SYMBOL(snd_util_memhdr_free); +EXPORT_SYMBOL(snd_util_mem_alloc); +EXPORT_SYMBOL(snd_util_mem_free); +EXPORT_SYMBOL(snd_util_mem_avail); +EXPORT_SYMBOL(__snd_util_mem_alloc); +EXPORT_SYMBOL(__snd_util_mem_free); +EXPORT_SYMBOL(__snd_util_memblk_new); -- cgit v1.3.1