From 263f7d61a4201cde16849b2d016251806e7418be Mon Sep 17 00:00:00 2001 From: Fan Wu Date: Thu, 20 Aug 2026 13:53:06 +0000 Subject: usb: typec: qcom-pmic-typec: disable cc_debounce_dwork on stop cc_debounce_dwork is queued from the set_cc() and start_toggling() callbacks, which run from TCPM's kthread worker. port_stop() returns before tcpm_unregister_port() destroys that worker. Flushing the worker during unregister may therefore run a callback which queues the delayed work after port_stop() has returned. The delayed work can then run after devres has freed pmic_typec_port. Use disable_delayed_work_sync() in port_stop() to cancel a pending instance and prevent the TCPM callbacks from queueing another one. This issue was found by an in-house static analysis tool. Fixes: a4422ff22142 ("usb: typec: qcom: Add Qualcomm PMIC Type-C driver") Cc: stable # v6.10+ Assisted-by: Codex:gpt-5.6 Signed-off-by: Fan Wu Acked-by: Heikki Krogerus Link: https://patch.msgid.link/20260820135307.153773-2-fanwu01@zju.edu.cn Signed-off-by: Greg Kroah-Hartman --- lib/llist.c | 94 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 94 insertions(+) create mode 100644 lib/llist.c (limited to 'lib/llist.c') diff --git a/lib/llist.c b/lib/llist.c new file mode 100644 index 000000000..f574c17a2 --- /dev/null +++ b/lib/llist.c @@ -0,0 +1,94 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Lock-less NULL terminated single linked list + * + * The basic atomic operation of this list is cmpxchg on long. On + * architectures that don't have NMI-safe cmpxchg implementation, the + * list can NOT be used in NMI handlers. So code that uses the list in + * an NMI handler should depend on CONFIG_ARCH_HAVE_NMI_SAFE_CMPXCHG. + * + * Copyright 2010,2011 Intel Corp. + * Author: Huang Ying + */ +#include +#include +#include + +/** + * llist_del_first - delete the first entry of lock-less list + * @head: the head for your lock-less list + * + * If list is empty, return NULL, otherwise, return the first entry + * deleted, this is the newest added one. + * + * Only one llist_del_first user can be used simultaneously with + * multiple llist_add users without lock. Because otherwise + * llist_del_first, llist_add, llist_add (or llist_del_all, llist_add, + * llist_add) sequence in another user may change @head->first->next, + * but keep @head->first. If multiple consumers are needed, please + * use llist_del_all or use lock between consumers. + */ +struct llist_node *llist_del_first(struct llist_head *head) +{ + struct llist_node *entry, *next; + + entry = smp_load_acquire(&head->first); + do { + if (entry == NULL) + return NULL; + next = READ_ONCE(entry->next); + } while (!try_cmpxchg(&head->first, &entry, next)); + + return entry; +} +EXPORT_SYMBOL_GPL(llist_del_first); + +/** + * llist_del_first_this - delete given entry of lock-less list if it is first + * @head: the head for your lock-less list + * @this: a list entry. + * + * If head of the list is given entry, delete and return %true else + * return %false. + * + * Multiple callers can safely call this concurrently with multiple + * llist_add() callers, providing all the callers offer a different @this. + */ +bool llist_del_first_this(struct llist_head *head, + struct llist_node *this) +{ + struct llist_node *entry, *next; + + /* acquire ensures orderig wrt try_cmpxchg() is llist_del_first() */ + entry = smp_load_acquire(&head->first); + do { + if (entry != this) + return false; + next = READ_ONCE(entry->next); + } while (!try_cmpxchg(&head->first, &entry, next)); + + return true; +} +EXPORT_SYMBOL_GPL(llist_del_first_this); + +/** + * llist_reverse_order - reverse order of a llist chain + * @head: first item of the list to be reversed + * + * Reverse the order of a chain of llist entries and return the + * new first entry. + */ +struct llist_node *llist_reverse_order(struct llist_node *head) +{ + struct llist_node *new_head = NULL; + + while (head) { + struct llist_node *tmp = head; + head = head->next; + tmp->next = new_head; + new_head = tmp; + } + + return new_head; +} +EXPORT_SYMBOL_GPL(llist_reverse_order); -- cgit v1.3.1