From c57da9a09debeaf7d6447e45d7b6ef8379521d21 Mon Sep 17 00:00:00 2001
From: DoctorRFer <224315159+DoctorRFer@users.noreply.github.com>
Date: Fri, 25 Sep 2026 11:09:19 +0000
Subject: [PATCH] fix(logging): don't route USE_SEGGER LOG_* through
 SEGGER_RTT_printf (#11970)

SEGGER_RTT_printf() only supports %c %d %u %x %X %s %p. A %f is
skipped without consuming its double from the va_list, so a later %s
reads part of that double as a pointer and HardFaults.

On CanaryOne (USE_SEGGER defined in variant.h) this resets the device
on every packet retransmission, via PacketHistory's
"Reusing slot aged %.3fs TRACE %s" log line. It also means CanaryOne
emits no logs over USB or the API, only over RTT.

RedirectablePrint::write() already mirrors every character to RTT
when USE_SEGGER is set, so drop the SEGGER-specific LOG_* macros and
use the normal logging path: full printf support, the existing log
semaphore, and RTT output preserved.

Tested on CanaryOne (v2.7.26.54e0d8d + this change, USE_SEGGER still
enabled): unacknowledged want_ack sends now retransmit twice and NAK
(err=5) without a reset, and logs reach USB/API again.
---
 src/DebugConfiguration.h | 19 +++++--------------
 1 file changed, 5 insertions(+), 14 deletions(-)

diff --git a/src/DebugConfiguration.h b/src/DebugConfiguration.h
index d155b1dfb5..99add71ab9 100644
--- a/src/DebugConfiguration.h
+++ b/src/DebugConfiguration.h
@@ -58,19 +58,11 @@ extern MemGet memGet;
 #endif
 #endif
 
-#ifdef USE_SEGGER
-// #undef DEBUG_PORT
-#define LOG_DEBUG(...) SEGGER_RTT_printf(0, __VA_ARGS__)
-#define LOG_INFO(...) SEGGER_RTT_printf(0, __VA_ARGS__)
-#define LOG_WARN(...) SEGGER_RTT_printf(0, __VA_ARGS__)
-#define LOG_ERROR(...) SEGGER_RTT_printf(0, __VA_ARGS__)
-#define LOG_CRIT(...) SEGGER_RTT_printf(0, __VA_ARGS__)
-#if MESHTASTIC_TRACE_LOGGING
-#define LOG_TRACE(...) SEGGER_RTT_printf(0, __VA_ARGS__)
-#else
-#define LOG_TRACE(...)
-#endif
-#else
+// USE_SEGGER no longer maps LOG_* to SEGGER_RTT_printf(): it has no float
+// support, and a skipped %f leaves its argument on the va_list, so a later %s
+// dereferences garbage and HardFaults (e.g. PacketHistory's
+// "Reusing slot aged %.3fs TRACE %s"). RedirectablePrint::write() already
+// mirrors every log character to RTT when USE_SEGGER is set.
 #if defined(DEBUG_PORT) && !defined(DEBUG_MUTE)
 #define LOG_DEBUG(...) DEBUG_PORT.log(MESHTASTIC_LOG_LEVEL_DEBUG, __VA_ARGS__)
 #define LOG_INFO(...) DEBUG_PORT.log(MESHTASTIC_LOG_LEVEL_INFO, __VA_ARGS__)
@@ -90,7 +82,6 @@ extern MemGet memGet;
 #define LOG_CRIT(...)
 #define LOG_TRACE(...)
 #endif
-#endif
 
 #if defined(DEBUG_HEAP)
 #define LOG_HEAP(...) DEBUG_PORT.log(MESHTASTIC_LOG_LEVEL_HEAP, __VA_ARGS__)