From 83e09bfa79d0ef588a38c04c997ee8091ea52617 Mon Sep 17 00:00:00 2001
From: zxystd <1051244836@qq.com>
Date: Wed, 13 Mar 2024 01:07:31 +0800
Subject: [PATCH] task: check if task is already in queue before trying lock,
 potentially fixing thread race crash issue.

---
 itl80211/openbsd/sys/_task.cpp | 14 ++++++++++----
 1 file changed, 10 insertions(+), 4 deletions(-)

diff --git a/itl80211/openbsd/sys/_task.cpp b/itl80211/openbsd/sys/_task.cpp
index df69a1a6f..8188b5426 100644
--- a/itl80211/openbsd/sys/_task.cpp
+++ b/itl80211/openbsd/sys/_task.cpp
@@ -276,16 +276,19 @@ int
 task_add(struct taskq *tq, struct task *w)
 {
     int rv = 0;
-//    IOLog("itlwm: taskq task_add %s\n", w->name);
+//    IOLog("itlwm: taskq task_add %s thread: %lld\n", w->name, thread_tid(current_thread()));
+    
+    if (ISSET(w->t_flags, TASK_ONQUEUE))
+        return (0);
 
     IORecursiveLockLock(tq->tq_mtx);
     if (ISSET(w->t_flags, TASK_ONQUEUE)) {
-        IOLog("itlwm: taskq task_add %s is already on queue\n", w->name);
+//        IOLog("itlwm: taskq task_add %s is already on queue thread: %lld\n", w->name, thread_tid(current_thread()));
         IORecursiveLockUnlock(tq->tq_mtx);
         return (0);
     }
     if (!ISSET(w->t_flags, TASK_ONQUEUE)) {
-        IOLog("itlwm: taskq task_add %s add to queue\n", w->name);
+//        IOLog("itlwm: taskq task_add %s add to queue thread: %lld\n", w->name, thread_tid(current_thread()));
         rv = 1;
         SET(w->t_flags, TASK_ONQUEUE);
         TAILQ_INSERT_TAIL(&tq->tq_worklist, w, t_entry);
@@ -302,7 +305,10 @@ int
 task_del(struct taskq *tq, struct task *w)
 {
     int rv = 0;
-//    IOLog("itlwm: taskq task_del %s\n", w->name);
+//    IOLog("itlwm: taskq task_del %s thread: %lld\n", w->name, thread_tid(current_thread()));
+    
+    if (!ISSET(w->t_flags, TASK_ONQUEUE))
+        return (0);
 
     IORecursiveLockLock(tq->tq_mtx);
     if (ISSET(w->t_flags, TASK_ONQUEUE)) {