From 1def26f83e83556d767754581fa52081ffb54b09 Mon Sep 17 00:00:00 2001
From: Sergej Schumilo <sergej@schumilo.de>
Date: Sat, 20 Jan 2024 21:26:18 +0100
Subject: [PATCH] fix non-ipt mode

---
 nyx/hypercall/hypercall.c | 13 +++++++++----
 nyx/interface.c           |  3 ---
 nyx/pt.c                  |  9 +++++++++
 3 files changed, 18 insertions(+), 7 deletions(-)

diff --git a/nyx/hypercall/hypercall.c b/nyx/hypercall/hypercall.c
index fa06af3201..7ee3025999 100644
--- a/nyx/hypercall/hypercall.c
+++ b/nyx/hypercall/hypercall.c
@@ -110,12 +110,17 @@ bool handle_hypercall_kafl_next_payload(struct kvm_run *run,
                                        REQUEST_SAVE_SNAPSHOT_ROOT_FIX_RIP);
                 setup_snapshot_once = true;
 
-                for (int i = 0; i < INTEL_PT_MAX_RANGES; i++) {
-                    if (GET_GLOBAL_STATE()->pt_ip_filter_configured[i]) {
-                        pt_enable_ip_filtering(cpu, i, true, false);
+                /* At this point we need to check if PT mode is enabled
+                 * and configured. Otherwise, libxdc_init() will fail.
+                 */
+                if(GET_GLOBAL_STATE()->nyx_pt && GET_GLOBAL_STATE()->cap_compile_time_tracing == false) {
+                    for (int i = 0; i < INTEL_PT_MAX_RANGES; i++) {
+                        if (GET_GLOBAL_STATE()->pt_ip_filter_configured[i]) {
+                            pt_enable_ip_filtering(cpu, i, true, false);
+                        }
                     }
+                    pt_init_decoder(cpu);
                 }
-                pt_init_decoder(cpu);
                 request_fast_vm_reload(GET_GLOBAL_STATE()->reload_state,
                                        REQUEST_LOAD_SNAPSHOT_ROOT);
 
diff --git a/nyx/interface.c b/nyx/interface.c
index 91ccd95986..6d1ced61b3 100644
--- a/nyx/interface.c
+++ b/nyx/interface.c
@@ -376,9 +376,6 @@ static void check_available_ipt_ranges(nyx_interface_state *s)
             }
         }
     }
-    else{
-        nyx_abort("KVM-Nyx support is missing...\n");
-    }
     close(kvm_fd);
 }
 
diff --git a/nyx/pt.c b/nyx/pt.c
index d78bc58522..33035ec671 100644
--- a/nyx/pt.c
+++ b/nyx/pt.c
@@ -227,6 +227,15 @@ void pt_init_decoder(CPUState *cpu)
     assert(GET_GLOBAL_STATE()->decoder == NULL);
     assert(GET_GLOBAL_STATE()->shared_bitmap_ptr != NULL);
     assert(GET_GLOBAL_STATE()->shared_bitmap_size != 0);
+
+
+    if (GET_GLOBAL_STATE()->pt_ip_filter_configured[0] == false && 
+        GET_GLOBAL_STATE()->pt_ip_filter_configured[1] == false && 
+        GET_GLOBAL_STATE()->pt_ip_filter_configured[2] == false && 
+        GET_GLOBAL_STATE()->pt_ip_filter_configured[3] == false) {
+        nyx_abort("Intel PT mode cannot be enabled without any IP filters configured...\n");
+    }
+
     GET_GLOBAL_STATE()->decoder =
         libxdc_init(filters, (void *(*)(void *, uint64_t, bool *))page_cache_fetch2,
                     GET_GLOBAL_STATE()->page_cache,