8294160: misc crash dump improvements

Reviewed-by: dholmes, vlivanov

src/hotspot/os/posix/signals_posix.cpp

@@ -627,9 +627,7 @@ int JVM_HANDLE_XXX_SIGNAL(int sig, siginfo_t* info,
 #ifndef ZERO
   // Check for UD trap caused by NOP patching.
   // If it is, patch return address to be deopt handler.
-  if (!signal_was_handled) {
-    address pc = os::Posix::ucontext_get_pc(uc);
-    assert(pc != NULL, "");
+  if (!signal_was_handled && pc != NULL && os::is_readable_pointer(pc)) {
     if (NativeDeoptInstruction::is_deopt_at(pc)) {
       CodeBlob* cb = CodeCache::find_blob(pc);
       if (cb != NULL && cb->is_compiled()) {

src/hotspot/os_cpu/linux_aarch64/os_linux_aarch64.cpp

@@ -129,6 +129,12 @@ frame os::fetch_frame_from_context(const void* ucVoid) {
   intptr_t* sp;
   intptr_t* fp;
   address epc = fetch_frame_from_context(ucVoid, &sp, &fp);
+  if (!is_readable_pointer(epc)) {
+    // Try to recover from calling into bad memory
+    // Assume new frame has not been set up, the same as
+    // compiled frame stack bang
+    return fetch_compiled_frame_from_context(ucVoid);
+  }
   return frame(sp, fp, epc);
 }
 
@@ -348,7 +354,7 @@ void os::print_tos_pc(outputStream *st, const void *context) {
   // Note: it may be unsafe to inspect memory near pc. For example, pc may
   // point to garbage if entry point in an nmethod is corrupted. Leave
   // this at the end, and hope for the best.
-  address pc = os::Posix::ucontext_get_pc(uc);
+  address pc = os::fetch_frame_from_context(uc).pc();
   print_instructions(st, pc, 4/*native instruction size*/);
   st->cr();
 }

src/hotspot/os_cpu/linux_x86/os_linux_x86.cpp

@@ -143,6 +143,12 @@ frame os::fetch_frame_from_context(const void* ucVoid) {
   intptr_t* sp;
   intptr_t* fp;
   address epc = fetch_frame_from_context(ucVoid, &sp, &fp);
+  if (!is_readable_pointer(epc)) {
+    // Try to recover from calling into bad memory
+    // Assume new frame has not been set up, the same as
+    // compiled frame stack bang
+    return fetch_compiled_frame_from_context(ucVoid);
+  }
   return frame(sp, fp, epc);
 }
 
@@ -582,7 +588,7 @@ void os::print_tos_pc(outputStream *st, const void *context) {
   // Note: it may be unsafe to inspect memory near pc. For example, pc may
   // point to garbage if entry point in an nmethod is corrupted. Leave
   // this at the end, and hope for the best.
-  address pc = os::Posix::ucontext_get_pc(uc);
+  address pc = os::fetch_frame_from_context(uc).pc();
   print_instructions(st, pc, sizeof(char));
   st->cr();
 }

src/hotspot/os_cpu/windows_x86/os_windows_x86.cpp

@@ -320,6 +320,12 @@ frame os::fetch_frame_from_context(const void* ucVoid) {
   intptr_t* sp;
   intptr_t* fp;
   address epc = fetch_frame_from_context(ucVoid, &sp, &fp);
+  if (!is_readable_pointer(epc)) {
+    // Try to recover from calling into bad memory
+    // Assume new frame has not been set up, the same as
+    // compiled frame stack bang
+    return frame(sp + 1, fp, (address)*sp);
+  }
   return frame(sp, fp, epc);
 }
 
@@ -456,7 +462,7 @@ void os::print_tos_pc(outputStream *st, const void *context) {
   // Note: it may be unsafe to inspect memory near pc. For example, pc may
   // point to garbage if entry point in an nmethod is corrupted. Leave
   // this at the end, and hope for the best.
-  address pc = (address)uc->REG_PC;
+  address pc = os::fetch_frame_from_context(uc).pc();
   print_instructions(st, pc, sizeof(char));
   st->cr();
 }

src/hotspot/share/oops/method.cpp

@@ -2323,6 +2323,8 @@ bool Method::is_valid_method(const Method* m) {
   } else if ((intptr_t(m) & (wordSize-1)) != 0) {
     // Quick sanity check on pointer.
     return false;
+  } else if (!os::is_readable_range(m, m + 1)) {
+    return false;
   } else if (m->is_shared()) {
     return CppVtables::is_valid_shared_method(m);
   } else if (Metaspace::contains_non_shared(m)) {