feat: add crash stack snapshots and context menu annotations

kernel/src/Api/BuildNo.hpp

@@ -12,4 +12,4 @@
 
 #pragma once
 
-#define MONTAUK_BUILD_NUMBER 106
+#define MONTAUK_BUILD_NUMBER 108

kernel/src/Api/CrashReportSyscall.hpp

@@ -34,6 +34,9 @@ namespace montauk::abi {
         out->codeSegment = rep.codeSegment;
         out->flags = rep.flags;
         out->stackSegment = rep.stackSegment;
+        out->stackWordCount = rep.stackWordCount;
+        for (int i = 0; i < rep.stackWordCount && i < CrashReport::StackSnapshotWords; i++)
+            out->stackWords[i] = rep.stackWords[i];
         out->pfPresent = rep.pfPresent;
         out->pfWrite = rep.pfWrite;
         out->pfUser = rep.pfUser;

kernel/src/Api/Syscall.hpp

@@ -780,6 +780,8 @@ namespace montauk::abi {
         uint64_t codeSegment;
         uint64_t flags;
         uint64_t stackSegment;
+        uint64_t stackWords[8];
+        uint8_t stackWordCount;
         uint8_t pfPresent : 1;
         uint8_t pfWrite : 1;
         uint8_t pfUser : 1;

kernel/src/Hal/IDT.cpp

@@ -127,6 +127,21 @@ namespace Hal {
             rep.stackPointer = regs->SP;
             rep.stackSegment = regs->SS;
 
+            // An indirect CALL pushes its real continuation address before a
+            // bad target faults on instruction fetch. Preserve a small stack
+            // snapshot while the dying process address space is still active;
+            // stackWords[0] will usually identify the caller even when RIP is
+            // corrupted data and cannot itself be symbolicated.
+            constexpr uint64_t snapshotBytes =
+                CrashReport::StackSnapshotWords * sizeof(uint64_t);
+            if (Memory::VMM::Paging::IsUserRangeAccessible(
+                    proc->pml4Phys, regs->SP, snapshotBytes, false)) {
+                auto* userStack = (const volatile uint64_t*)regs->SP;
+                for (int word = 0; word < CrashReport::StackSnapshotWords; word++)
+                    rep.stackWords[word] = userStack[word];
+                rep.stackWordCount = CrashReport::StackSnapshotWords;
+            }
+
             if (i == 0x0E) {
                 // Page fault: read CR2 for faulting address
                 asm volatile("mov %%cr2, %0" : "=r"(rep.faultingAddress));

kernel/src/Sched/CrashReport.hpp

@@ -11,6 +11,7 @@
 namespace CrashReport {
 
 static constexpr int MaxReports = 8;
+static constexpr int StackSnapshotWords = 8;
 
 struct Report {
     int pid;
@@ -24,6 +25,8 @@ struct Report {
     uint64_t codeSegment;
     uint64_t flags;
     uint64_t stackSegment;
+    uint64_t stackWords[StackSnapshotWords];
+    uint8_t stackWordCount;
 
     // Page fault error code bits (vector 0xE / page fault only)
     uint8_t pfPresent : 1;

programs/include/Api/Syscall.hpp

@@ -718,6 +718,8 @@ namespace montauk::abi {
         uint64_t codeSegment;
         uint64_t flags;
         uint64_t stackSegment;
+        uint64_t stackWords[8];
+        uint8_t stackWordCount;
         uint8_t pfPresent : 1;
         uint8_t pfWrite : 1;
         uint8_t pfUser : 1;

programs/include/gui/mtk/widgets.hpp

@@ -40,6 +40,8 @@ struct ContextMenuItem {
     const char* label;
     int id;
     bool enabled;
+    const char* shortcut;
+    bool separator_after;
 };
 
 enum ContextMenuResult : int {
@@ -226,6 +228,19 @@ inline void draw_context_menu(Canvas& c,
         Color label_color = items[i].enabled ? theme.text : theme.text_muted;
         context_menu_draw_label(c, menu.x + 12, item.y + (item.h - fh) / 2,
                                 items[i].label, label_color, font, font_size);
+        if (items[i].shortcut && items[i].shortcut[0]) {
+            int shortcut_w = font && font->valid && font_size > 0
+                ? font->measure_text(items[i].shortcut, font_size)
+                : text_width(items[i].shortcut);
+            context_menu_draw_label(c, menu.x + menu.w - 12 - shortcut_w,
+                                    item.y + (item.h - fh) / 2,
+                                    items[i].shortcut, theme.text_muted,
+                                    font, font_size);
+        }
+        if (items[i].separator_after) {
+            c.hline(menu.x + 10, item.y + item.h - 1,
+                    menu.w - 20, theme.border);
+        }
     }
 }
 

programs/src/crashpad/main.cpp

@@ -212,6 +212,28 @@ static void render() {
         y += SECTION_GAP;
     }
 
+    if (g_report.stackWordCount != 0) {
+        section_header(c, y, w, fh, "Stack Snapshot");
+        for (int i = 0; i < g_report.stackWordCount && i < 8; i++) {
+            char label[24] = "Stack + 0x00";
+            static const char digits[] = "0123456789ABCDEF";
+            unsigned offset = (unsigned)i * 8;
+            label[10] = digits[(offset >> 4) & 0xF];
+            label[11] = digits[offset & 0xF];
+            if (i == 0) {
+                label[12] = ' ';
+                label[13] = '(';
+                label[14] = 'r';
+                label[15] = 'e';
+                label[16] = 't';
+                label[17] = ')';
+                label[18] = '\0';
+            }
+            format_hex16(hexbuf, g_report.stackWords[i]);
+            table_row(c, y, row_h, COL1_W, w, rowIdx++, label, hexbuf, VALUE_COL);
+        }
+    }
+
     g_win.present();
 }
 
@@ -248,6 +270,14 @@ static void render_console() {
     emit_kv_hex("RFLAGS", g_report.flags);
     if (g_report.exceptionVector == 0x0E)
         emit_kv_hex("CR2 (fault addr)", g_report.faultingAddress);
+    for (int i = 0; i < g_report.stackWordCount && i < 8; i++) {
+        char key[] = "Stack + 0x00";
+        static const char digits[] = "0123456789ABCDEF";
+        unsigned offset = (unsigned)i * 8;
+        key[10] = digits[(offset >> 4) & 0xF];
+        key[11] = digits[offset & 0xF];
+        emit_kv_hex(key, g_report.stackWords[i]);
+    }
     emit("\n");
 }