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/net/wireguard/queueing.c | 109 +++++++++++++++++++++++++++++++++++++++ 1 file changed, 109 insertions(+) create mode 100644 drivers/net/wireguard/queueing.c (limited to 'drivers/net/wireguard/queueing.c') diff --git a/drivers/net/wireguard/queueing.c b/drivers/net/wireguard/queueing.c new file mode 100644 index 000000000..26d235d15 --- /dev/null +++ b/drivers/net/wireguard/queueing.c @@ -0,0 +1,109 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (C) 2015-2019 Jason A. Donenfeld . All Rights Reserved. + */ + +#include "queueing.h" +#include + +struct multicore_worker __percpu * +wg_packet_percpu_multicore_worker_alloc(work_func_t function, void *ptr) +{ + int cpu; + struct multicore_worker __percpu *worker = alloc_percpu(struct multicore_worker); + + if (!worker) + return NULL; + + for_each_possible_cpu(cpu) { + per_cpu_ptr(worker, cpu)->ptr = ptr; + INIT_WORK(&per_cpu_ptr(worker, cpu)->work, function); + } + return worker; +} + +int wg_packet_queue_init(struct crypt_queue *queue, work_func_t function, + unsigned int len) +{ + int ret; + + memset(queue, 0, sizeof(*queue)); + queue->last_cpu = -1; + ret = ptr_ring_init(&queue->ring, len, GFP_KERNEL); + if (ret) + return ret; + queue->worker = wg_packet_percpu_multicore_worker_alloc(function, queue); + if (!queue->worker) { + ptr_ring_cleanup(&queue->ring, NULL); + return -ENOMEM; + } + return 0; +} + +void wg_packet_queue_free(struct crypt_queue *queue, bool purge) +{ + free_percpu(queue->worker); + WARN_ON(!purge && !__ptr_ring_empty(&queue->ring)); + ptr_ring_cleanup(&queue->ring, purge ? __skb_array_destroy_skb : NULL); +} + +#define NEXT(skb) ((skb)->prev) +#define STUB(queue) ((struct sk_buff *)&queue->empty) + +void wg_prev_queue_init(struct prev_queue *queue) +{ + NEXT(STUB(queue)) = NULL; + queue->head = queue->tail = STUB(queue); + queue->peeked = NULL; + atomic_set(&queue->count, 0); + BUILD_BUG_ON( + offsetof(struct sk_buff, next) != offsetof(struct prev_queue, empty.next) - + offsetof(struct prev_queue, empty) || + offsetof(struct sk_buff, prev) != offsetof(struct prev_queue, empty.prev) - + offsetof(struct prev_queue, empty)); +} + +static void __wg_prev_queue_enqueue(struct prev_queue *queue, struct sk_buff *skb) +{ + WRITE_ONCE(NEXT(skb), NULL); + WRITE_ONCE(NEXT(xchg_release(&queue->head, skb)), skb); +} + +bool wg_prev_queue_enqueue(struct prev_queue *queue, struct sk_buff *skb) +{ + if (!atomic_add_unless(&queue->count, 1, MAX_QUEUED_PACKETS)) + return false; + __wg_prev_queue_enqueue(queue, skb); + return true; +} + +struct sk_buff *wg_prev_queue_dequeue(struct prev_queue *queue) +{ + struct sk_buff *tail = queue->tail, *next = smp_load_acquire(&NEXT(tail)); + + if (tail == STUB(queue)) { + if (!next) + return NULL; + queue->tail = next; + tail = next; + next = smp_load_acquire(&NEXT(next)); + } + if (next) { + queue->tail = next; + atomic_dec(&queue->count); + return tail; + } + if (tail != READ_ONCE(queue->head)) + return NULL; + __wg_prev_queue_enqueue(queue, STUB(queue)); + next = smp_load_acquire(&NEXT(tail)); + if (next) { + queue->tail = next; + atomic_dec(&queue->count); + return tail; + } + return NULL; +} + +#undef NEXT +#undef STUB -- cgit v1.3.1