fixup! chore(core): use cortex-m33 stack protection

trezor · Nov 15, 2023 · 3f94ef5 · 3f94ef5
1 parent 26e3e41
commit 3f94ef5
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Showing 2 changed files with 7 additions and 2 deletions.
diff --git a/core/embed/bootloader_ci/memory_stm32u5a.ld b/core/embed/bootloader_ci/memory_stm32u5a.ld
@@ -14,7 +14,7 @@ MEMORY {
 }
 
 main_stack_base = ORIGIN(SRAM2) + SIZEOF(.stack); /* 8-byte aligned full descending stack */
-_sstack = ORIGIN(SRAM2) + 0x100;
+_sstack = ORIGIN(SRAM2);
 _estack = main_stack_base;
 
 /* used by the startup code to populate variables used by the C code */
@@ -81,7 +81,7 @@ SECTIONS {
   } >SRAM1
 
   .stack : ALIGN(8) {
-    . = 16K + 0x100; /* Exactly 16K allocated for stack. Overflow causes MemManage fault (when using MPU). */
+    . = 16K; /* Overflow causes UsageFault */
   } >SRAM2
 
   .sensitive : ALIGN(512) {

diff --git a/core/embed/bootloader_ci/startup_stm32u5.s b/core/embed/bootloader_ci/startup_stm32u5.s
@@ -5,6 +5,11 @@
   .global reset_handler
   .type reset_handler, STT_FUNC
 reset_handler:
+  // set the stack protection
+  ldr r0, =_sstack
+  add r0, r0, #16        // padding
+  msr MSPLIM, r0
+
   // setup environment for subsequent stage of code
   ldr r2, =0             // r2 - the word-sized value to be written