From 95b03592dc0b753dfcfa30c1cc17d8e1f2a547f9 Mon Sep 17 00:00:00 2001
From: Theo Arends <11044339+arendst@users.noreply.github.com>
Date: Tue, 30 Jan 2024 16:57:45 +0100
Subject: [PATCH] Add ISR logging failsafe

---
 tasmota/tasmota_support/support.ino | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/tasmota/tasmota_support/support.ino b/tasmota/tasmota_support/support.ino
index 8966df9f2..766a821dc 100755
--- a/tasmota/tasmota_support/support.ino
+++ b/tasmota/tasmota_support/support.ino
@@ -2570,6 +2570,15 @@ uint32_t HighestLogLevel() {
 }
 
 void AddLog(uint32_t loglevel, PGM_P formatP, ...) {
+#ifdef ESP32
+  if (xPortInIsrContext()) {
+    // When called from an ISR, you should not send out logs.
+    // Allocating memory from within an ISR is a big no-no.
+    // Also long-time blocking like sending logs (especially to a syslog server) 
+    // is also really not a good idea from an ISR call.
+    return;
+  }
+#endif
   uint32_t highest_loglevel = HighestLogLevel();
 
   // If no logging is requested then do not access heap to fight fragmentation