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/dibs/dibs_loopback.h | 57 ++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 57 insertions(+) create mode 100644 drivers/dibs/dibs_loopback.h (limited to 'drivers/dibs/dibs_loopback.h') diff --git a/drivers/dibs/dibs_loopback.h b/drivers/dibs/dibs_loopback.h new file mode 100644 index 000000000..0664f6a8e --- /dev/null +++ b/drivers/dibs/dibs_loopback.h @@ -0,0 +1,57 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * dibs loopback (aka loopback-ism) device structure definitions. + * + * Copyright (c) 2024, Alibaba Inc. + * + * Author: Wen Gu + * Tony Lu + * + */ + +#ifndef _DIBS_LOOPBACK_H +#define _DIBS_LOOPBACK_H + +#include +#include +#include +#include +#include + +#if IS_ENABLED(CONFIG_DIBS_LO) +#define DIBS_LO_DMBS_HASH_BITS 12 +#define DIBS_LO_MAX_DMBS 5000 + +struct dibs_lo_dmb_node { + struct hlist_node list; + u64 token; + u32 len; + u32 sba_idx; + void *cpu_addr; + dma_addr_t dma_addr; + refcount_t refcnt; +}; + +struct dibs_lo_dev { + struct dibs_dev *dibs; + atomic_t dmb_cnt; + rwlock_t dmb_ht_lock; + DECLARE_BITMAP(sba_idx_mask, DIBS_LO_MAX_DMBS); + DECLARE_HASHTABLE(dmb_ht, DIBS_LO_DMBS_HASH_BITS); + wait_queue_head_t ldev_release; +}; + +int dibs_loopback_init(void); +void dibs_loopback_exit(void); +#else +static inline int dibs_loopback_init(void) +{ + return 0; +} + +static inline void dibs_loopback_exit(void) +{ +} +#endif + +#endif /* _DIBS_LOOPBACK_H */ -- cgit v1.3.1