From abae461c3b81b77966c8adfae5438a8b0a813c6b Mon Sep 17 00:00:00 2001
From: Tim Pambor <tim.pambor@codewrights.de>
Date: Mon, 23 Jun 2025 11:28:16 +0200
Subject: [PATCH] logging: Skip messages generated by logging thread

---
 include/zephyr/logging/log_internal.h | 2 ++
 subsys/logging/log_core.c             | 6 +++---
 subsys/logging/log_msg.c              | 4 ++++
 3 files changed, 9 insertions(+), 3 deletions(-)

diff --git a/include/zephyr/logging/log_internal.h b/include/zephyr/logging/log_internal.h
index cc2c8bd0ec648..e1155d48d6644 100644
--- a/include/zephyr/logging/log_internal.h
+++ b/include/zephyr/logging/log_internal.h
@@ -163,6 +163,8 @@ static inline bool z_log_is_local_domain(uint8_t domain_id)
  */
 log_timestamp_t z_log_timestamp(void);
 
+extern k_tid_t log_core_proc_tid;
+
 #ifdef __cplusplus
 }
 #endif
diff --git a/subsys/logging/log_core.c b/subsys/logging/log_core.c
index f5fb7c59101e6..e02aeb1aa7313 100644
--- a/subsys/logging/log_core.c
+++ b/subsys/logging/log_core.c
@@ -104,7 +104,7 @@ static bool panic_mode;
 static bool backend_attached;
 static atomic_t buffered_cnt;
 static atomic_t dropped_cnt;
-static k_tid_t proc_tid;
+k_tid_t log_core_proc_tid;
 static struct k_timer log_process_thread_timer;
 
 static log_timestamp_t dummy_timestamp(void);
@@ -168,7 +168,7 @@ static void z_log_msg_post_finalize(void)
 		(void)log_process();
 
 		k_spin_unlock(&process_lock, key);
-	} else if (proc_tid != NULL) {
+	} else if (log_core_proc_tid != NULL) {
 		/*
 		 * If CONFIG_LOG_PROCESS_TRIGGER_THRESHOLD == 1,
 		 * timer is never needed. We release the processing
@@ -386,7 +386,7 @@ void log_thread_trigger(void)
 
 static void thread_set(k_tid_t process_tid)
 {
-	proc_tid = process_tid;
+	log_core_proc_tid = process_tid;
 
 	if (IS_ENABLED(CONFIG_LOG_MODE_IMMEDIATE)) {
 		return;
diff --git a/subsys/logging/log_msg.c b/subsys/logging/log_msg.c
index f9b760f1e58f3..4b6455885eec7 100644
--- a/subsys/logging/log_msg.c
+++ b/subsys/logging/log_msg.c
@@ -289,6 +289,10 @@ void z_impl_z_log_msg_static_create(const void *source,
 		return;
 	}
 
+	// Do not log messages generated by logging thread
+	if(log_core_proc_tid == k_current_get())
+		return;
+
 	struct log_msg_desc out_desc = desc;
 	int inlen = desc.package_len;
 	struct log_msg *msg;