diff --git a/3_RootkitTechniques/3.1_syscall_hooking/rootkit.c b/3_RootkitTechniques/3.1_syscall_hooking/rootkit.c
index c7a8f11..fd28767 100644
--- a/3_RootkitTechniques/3.1_syscall_hooking/rootkit.c
+++ b/3_RootkitTechniques/3.1_syscall_hooking/rootkit.c
@@ -61,7 +61,7 @@
  * the WP bit, so we write our own instead */
 inline void cr0_write(unsigned long cr0)
 {
-    asm volatile("mov %0,%%cr0" : "+r"(cr0), "+m"(__force_order));
+    asm volatile("mov %0,%%cr0" : "+r"(cr0) : : "memory");
 }
 
 /* Bit 16 in the cr0 register is the W(rite) P(rotection) bit which
diff --git a/3_RootkitTechniques/3.2_kill_signalling/ftrace_helper.h b/3_RootkitTechniques/3.2_kill_signalling/ftrace_helper.h
index 1624ce4..ab74ace 100644
--- a/3_RootkitTechniques/3.2_kill_signalling/ftrace_helper.h
+++ b/3_RootkitTechniques/3.2_kill_signalling/ftrace_helper.h
@@ -78,8 +78,9 @@
 }
 
 /* See comment below within fh_install_hook() */
-static void notrace fh_ftrace_thunk(unsigned long ip, unsigned long parent_ip, struct ftrace_ops *ops, struct pt_regs *regs)
+static void notrace fh_ftrace_thunk(unsigned long ip, unsigned long parent_ip, struct ftrace_ops *ops, struct ftrace_regs *fregs)
 {
+    struct pt_regs *regs = ftrace_get_regs(fregs);
     struct ftrace_hook *hook = container_of(ops, struct ftrace_hook, ops);
 
 #if USE_FENTRY_OFFSET
@@ -112,7 +113,7 @@
      * (see USE_FENTRY_OFFSET). */
     hook->ops.func = fh_ftrace_thunk;
     hook->ops.flags = FTRACE_OPS_FL_SAVE_REGS
-            | FTRACE_OPS_FL_RECURSION_SAFE
+            | FTRACE_OPS_FL_RECURSION
             | FTRACE_OPS_FL_IPMODIFY;
 
     err = ftrace_set_filter_ip(&hook->ops, hook->address, 0, 0);
diff --git a/3_RootkitTechniques/3.2_kill_signalling/rootkit.c b/3_RootkitTechniques/3.2_kill_signalling/rootkit.c
index 416f275..bc69385 100644
--- a/3_RootkitTechniques/3.2_kill_signalling/rootkit.c
+++ b/3_RootkitTechniques/3.2_kill_signalling/rootkit.c
@@ -60,6 +60,7 @@
     {
         return orig_kill(regs);
     }
+    return -999;
 }
 #else
 /* This is the old way of declaring a syscall hook */
diff --git a/3_RootkitTechniques/3.3_set_root/ftrace_helper.h b/3_RootkitTechniques/3.3_set_root/ftrace_helper.h
index 808453d..ed2d8cd 100644
--- a/3_RootkitTechniques/3.3_set_root/ftrace_helper.h
+++ b/3_RootkitTechniques/3.3_set_root/ftrace_helper.h
@@ -92,8 +92,9 @@
 }
 
 /* See comment below within fh_install_hook() */
-static void notrace fh_ftrace_thunk(unsigned long ip, unsigned long parent_ip, struct ftrace_ops *ops, struct pt_regs *regs)
+static void notrace fh_ftrace_thunk(unsigned long ip, unsigned long parent_ip, struct ftrace_ops *ops, struct ftrace_regs *fregs)
 {
+    struct pt_regs *regs = ftrace_get_regs(fregs);
     struct ftrace_hook *hook = container_of(ops, struct ftrace_hook, ops);
 
 #if USE_FENTRY_OFFSET
@@ -126,7 +127,7 @@
      * (see USE_FENTRY_OFFSET). */
     hook->ops.func = fh_ftrace_thunk;
     hook->ops.flags = FTRACE_OPS_FL_SAVE_REGS
-            | FTRACE_OPS_FL_RECURSION_SAFE
+            | FTRACE_OPS_FL_RECURSION
             | FTRACE_OPS_FL_IPMODIFY;
 
     err = ftrace_set_filter_ip(&hook->ops, hook->address, 0, 0);
diff --git a/3_RootkitTechniques/3.4_hiding_directories/ftrace_helper.h b/3_RootkitTechniques/3.4_hiding_directories/ftrace_helper.h
index 808453d..ed2d8cd 100644
--- a/3_RootkitTechniques/3.4_hiding_directories/ftrace_helper.h
+++ b/3_RootkitTechniques/3.4_hiding_directories/ftrace_helper.h
@@ -92,8 +92,9 @@
 }
 
 /* See comment below within fh_install_hook() */
-static void notrace fh_ftrace_thunk(unsigned long ip, unsigned long parent_ip, struct ftrace_ops *ops, struct pt_regs *regs)
+static void notrace fh_ftrace_thunk(unsigned long ip, unsigned long parent_ip, struct ftrace_ops *ops, struct ftrace_regs *fregs)
 {
+    struct pt_regs *regs = ftrace_get_regs(fregs);
     struct ftrace_hook *hook = container_of(ops, struct ftrace_hook, ops);
 
 #if USE_FENTRY_OFFSET
@@ -126,7 +127,7 @@
      * (see USE_FENTRY_OFFSET). */
     hook->ops.func = fh_ftrace_thunk;
     hook->ops.flags = FTRACE_OPS_FL_SAVE_REGS
-            | FTRACE_OPS_FL_RECURSION_SAFE
+            | FTRACE_OPS_FL_RECURSION
             | FTRACE_OPS_FL_IPMODIFY;
 
     err = ftrace_set_filter_ip(&hook->ops, hook->address, 0, 0);
diff --git a/3_RootkitTechniques/3.5_hiding_processes/ftrace_helper.h b/3_RootkitTechniques/3.5_hiding_processes/ftrace_helper.h
index 808453d..ed2d8cd 100644
--- a/3_RootkitTechniques/3.5_hiding_processes/ftrace_helper.h
+++ b/3_RootkitTechniques/3.5_hiding_processes/ftrace_helper.h
@@ -92,8 +92,9 @@
 }
 
 /* See comment below within fh_install_hook() */
-static void notrace fh_ftrace_thunk(unsigned long ip, unsigned long parent_ip, struct ftrace_ops *ops, struct pt_regs *regs)
+static void notrace fh_ftrace_thunk(unsigned long ip, unsigned long parent_ip, struct ftrace_ops *ops, struct ftrace_regs *fregs)
 {
+    struct pt_regs *regs = ftrace_get_regs(fregs);
     struct ftrace_hook *hook = container_of(ops, struct ftrace_hook, ops);
 
 #if USE_FENTRY_OFFSET
@@ -126,7 +127,7 @@
      * (see USE_FENTRY_OFFSET). */
     hook->ops.func = fh_ftrace_thunk;
     hook->ops.flags = FTRACE_OPS_FL_SAVE_REGS
-            | FTRACE_OPS_FL_RECURSION_SAFE
+            | FTRACE_OPS_FL_RECURSION
             | FTRACE_OPS_FL_IPMODIFY;
 
     err = ftrace_set_filter_ip(&hook->ops, hook->address, 0, 0);
diff --git a/3_RootkitTechniques/3.6_hiding_ports/ftrace_helper.h b/3_RootkitTechniques/3.6_hiding_ports/ftrace_helper.h
index 808453d..ed2d8cd 100644
--- a/3_RootkitTechniques/3.6_hiding_ports/ftrace_helper.h
+++ b/3_RootkitTechniques/3.6_hiding_ports/ftrace_helper.h
@@ -92,8 +92,9 @@
 }
 
 /* See comment below within fh_install_hook() */
-static void notrace fh_ftrace_thunk(unsigned long ip, unsigned long parent_ip, struct ftrace_ops *ops, struct pt_regs *regs)
+static void notrace fh_ftrace_thunk(unsigned long ip, unsigned long parent_ip, struct ftrace_ops *ops, struct ftrace_regs *fregs)
 {
+    struct pt_regs *regs = ftrace_get_regs(fregs);
     struct ftrace_hook *hook = container_of(ops, struct ftrace_hook, ops);
 
 #if USE_FENTRY_OFFSET
@@ -126,7 +127,7 @@
      * (see USE_FENTRY_OFFSET). */
     hook->ops.func = fh_ftrace_thunk;
     hook->ops.flags = FTRACE_OPS_FL_SAVE_REGS
-            | FTRACE_OPS_FL_RECURSION_SAFE
+            | FTRACE_OPS_FL_RECURSION
             | FTRACE_OPS_FL_IPMODIFY;
 
     err = ftrace_set_filter_ip(&hook->ops, hook->address, 0, 0);
diff --git a/3_RootkitTechniques/3.7_char_interfering/ftrace_helper.h b/3_RootkitTechniques/3.7_char_interfering/ftrace_helper.h
index 808453d..ed2d8cd 100644
--- a/3_RootkitTechniques/3.7_char_interfering/ftrace_helper.h
+++ b/3_RootkitTechniques/3.7_char_interfering/ftrace_helper.h
@@ -92,8 +92,9 @@
 }
 
 /* See comment below within fh_install_hook() */
-static void notrace fh_ftrace_thunk(unsigned long ip, unsigned long parent_ip, struct ftrace_ops *ops, struct pt_regs *regs)
+static void notrace fh_ftrace_thunk(unsigned long ip, unsigned long parent_ip, struct ftrace_ops *ops, struct ftrace_regs *fregs)
 {
+    struct pt_regs *regs = ftrace_get_regs(fregs);
     struct ftrace_hook *hook = container_of(ops, struct ftrace_hook, ops);
 
 #if USE_FENTRY_OFFSET
@@ -126,7 +127,7 @@
      * (see USE_FENTRY_OFFSET). */
     hook->ops.func = fh_ftrace_thunk;
     hook->ops.flags = FTRACE_OPS_FL_SAVE_REGS
-            | FTRACE_OPS_FL_RECURSION_SAFE
+            | FTRACE_OPS_FL_RECURSION
             | FTRACE_OPS_FL_IPMODIFY;
 
     err = ftrace_set_filter_ip(&hook->ops, hook->address, 0, 0);
diff --git a/3_RootkitTechniques/3.9_hiding_logged_in_users/ftrace_helper.h b/3_RootkitTechniques/3.9_hiding_logged_in_users/ftrace_helper.h
index 808453d..ed2d8cd 100644
--- a/3_RootkitTechniques/3.9_hiding_logged_in_users/ftrace_helper.h
+++ b/3_RootkitTechniques/3.9_hiding_logged_in_users/ftrace_helper.h
@@ -92,8 +92,9 @@
 }
 
 /* See comment below within fh_install_hook() */
-static void notrace fh_ftrace_thunk(unsigned long ip, unsigned long parent_ip, struct ftrace_ops *ops, struct pt_regs *regs)
+static void notrace fh_ftrace_thunk(unsigned long ip, unsigned long parent_ip, struct ftrace_ops *ops, struct ftrace_regs *fregs)
 {
+    struct pt_regs *regs = ftrace_get_regs(fregs);
     struct ftrace_hook *hook = container_of(ops, struct ftrace_hook, ops);
 
 #if USE_FENTRY_OFFSET
@@ -126,7 +127,7 @@
      * (see USE_FENTRY_OFFSET). */
     hook->ops.func = fh_ftrace_thunk;
     hook->ops.flags = FTRACE_OPS_FL_SAVE_REGS
-            | FTRACE_OPS_FL_RECURSION_SAFE
+            | FTRACE_OPS_FL_RECURSION
             | FTRACE_OPS_FL_IPMODIFY;
 
     err = ftrace_set_filter_ip(&hook->ops, hook->address, 0, 0);