From 41a6f2bc8da53e3277c6b183bdc167399245c858 Mon Sep 17 00:00:00 2001
From: Chris <52449218+shadow578@users.noreply.github.com>
Date: Wed, 1 Nov 2023 01:10:37 +0100
Subject: [PATCH] =?UTF-8?q?=F0=9F=A7=91=E2=80=8D=F0=9F=92=BB=20Improve=20P?=
=?UTF-8?q?OSTMORTEM=5FDEBUGGING=20(#26374)?=
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Co-authored-by: Scott Lahteine <thinkyhead@users.noreply.github.com>
---
Marlin/src/HAL/shared/backtrace/unwarmbytab.cpp | 7 ++++++-
Marlin/src/HAL/shared/cpu_exception/exception_arm.cpp | 2 --
2 files changed, 6 insertions(+), 3 deletions(-)
diff --git a/Marlin/src/HAL/shared/backtrace/unwarmbytab.cpp b/Marlin/src/HAL/shared/backtrace/unwarmbytab.cpp
index 148927a19f5..bd87b6731cd 100644
--- a/Marlin/src/HAL/shared/backtrace/unwarmbytab.cpp
+++ b/Marlin/src/HAL/shared/backtrace/unwarmbytab.cpp
@@ -55,7 +55,12 @@ static const char *UnwTabGetFunctionName(const UnwindCallbacks *cb, uint32_t add
return nullptr;
if ((flag_word & 0xFF000000) == 0xFF000000) {
- return (const char *)(address - 4 - (flag_word & 0x00FFFFFF));
+ const uint32_t fn_name_addr = address - 4 - (flag_word & 0x00FFFFFF);
+
+ // Ensure the address is readable to avoid returning a bogus pointer
+ uint8_t dummy = 0;
+ if (cb->readB(fn_name_addr, &dummy))
+ return (const char *)fn_name_addr;
}
return nullptr;
}
diff --git a/Marlin/src/HAL/shared/cpu_exception/exception_arm.cpp b/Marlin/src/HAL/shared/cpu_exception/exception_arm.cpp
index e54661c7707..3c514f58a9c 100644
--- a/Marlin/src/HAL/shared/cpu_exception/exception_arm.cpp
+++ b/Marlin/src/HAL/shared/cpu_exception/exception_arm.cpp
@@ -279,8 +279,6 @@ void CommonHandler_C(ContextStateFrame * frame, unsigned long lr, unsigned long
if (!faulted_from_exception) { // Not sure about the non_usage_fault, we want to try anyway, don't we ? && !non_usage_fault_occurred)
// Try to resume to our handler here
CFSR |= CFSR; // The ARM programmer manual says you must write to 1 all fault bits to clear them so this instruction is correct
- // The frame will not be valid when returning anymore, let's clean it
- savedFrame.CFSR = 0;
frame->pc = (uint32_t)resume_from_fault; // Patch where to return to
frame->lr = 0xDEADBEEF; // If our handler returns (it shouldn't), let's make it trigger an exception immediately