diff --git a/src/ehypercall.h b/src/ehypercall.h
index 8f9def7..3ab906c 100644
--- a/src/ehypercall.h
+++ b/src/ehypercall.h
@@ -48,13 +48,16 @@ static inline unsigned long igloo_hypercall4(unsigned long num, unsigned long ar
     return reg0;
 
 #elif defined(CONFIG_X86_64)
-    unsigned long reg0 = num;
+    register unsigned long reg0 asm("rax") = num;
+    register unsigned long reg1 asm("rdi") = arg1;
+    register unsigned long reg2 asm("rsi") = arg2;
+    register unsigned long reg3 asm("rdx") = arg3;
     register unsigned long reg4 asm("r10") = arg4; // r10 used for 4th arg in syscall ABI
 
     asm volatile(
         "outl %%eax, $0x88"
         : "+a"(reg0)           // hypercall num + return value in rax
-        : "D"(arg1), "S"(arg2), "d"(arg3), "r"(reg4)
+        : "r"(reg1), "r"(reg2), "r"(reg3), "r"(reg4)
         : "memory"
     );
 
@@ -62,12 +65,16 @@ static inline unsigned long igloo_hypercall4(unsigned long num, unsigned long ar
 
 #elif defined(CONFIG_I386)
     // Matches the "other implementation" (standard Linux Syscall ABI)
-    unsigned long reg0 = num;
+    register unsigned long reg0 asm("eax") = num;
+    register unsigned long reg1 asm("ebx") = arg1;
+    register unsigned long reg2 asm("ecx") = arg2;
+    register unsigned long reg3 asm("edx") = arg3;
+    register unsigned long reg4 asm("esi") = arg4;
 
     asm volatile(
         "outl %%eax, $0x88"
         : "+a"(reg0)           // hypercall num + return value in eax
-        : "b"(arg1), "c"(arg2), "d"(arg3), "S"(arg4)
+        : "r"(reg1), "r"(reg2), "r"(reg3), "r"(reg4)
         : "memory"
     );
 
@@ -124,4 +131,4 @@ static inline unsigned long igloo_hypercall4(unsigned long num, unsigned long ar
 #error "No igloo_hypercall4 support for architecture"
 #endif
 }
-#endif
\ No newline at end of file
+#endif
diff --git a/src/hooks/block_mounts.c b/src/hooks/block_mounts.c
index babcc6d..3359640 100644
--- a/src/hooks/block_mounts.c
+++ b/src/hooks/block_mounts.c
@@ -6,7 +6,7 @@
 #include <linux/sched.h>
 #include <linux/slab.h>
 #include <linux/binfmts.h>
-#include "hypercall.h"
+#include "igloo_hypercall.h"
 #include "igloo.h"
 
 bool igloo_should_block_mount(struct path *path);
diff --git a/src/hooks/igloo_open.c b/src/hooks/igloo_open.c
index 0cea9ce..fec3651 100644
--- a/src/hooks/igloo_open.c
+++ b/src/hooks/igloo_open.c
@@ -6,7 +6,7 @@
 #include <linux/sched.h>
 #include <linux/slab.h>
 #include <linux/file.h>
-#include "hypercall.h"
+#include "igloo_hypercall.h"
 #include "igloo.h"
 #include <linux/binfmts.h>
 #include <trace/syscall.h>
diff --git a/src/hooks/ioctl_hc.c b/src/hooks/ioctl_hc.c
index a2fc890..831d6f1 100644
--- a/src/hooks/ioctl_hc.c
+++ b/src/hooks/ioctl_hc.c
@@ -5,7 +5,7 @@
 #include <linux/mm.h>
 #include <linux/sched.h>
 #include <linux/slab.h>
-#include "hypercall.h"
+#include "igloo_hypercall.h"
 #include "igloo.h"
 #include <linux/binfmts.h>
 #include <trace/syscall.h>
diff --git a/src/hooks/signal_hc.c b/src/hooks/signal_hc.c
index 4e5d07b..0fc8058 100644
--- a/src/hooks/signal_hc.c
+++ b/src/hooks/signal_hc.c
@@ -5,7 +5,7 @@
 #include <linux/version.h>
 #include <linux/sched.h>
 #include <linux/slab.h>
-#include "hypercall.h"
+#include "igloo_hypercall.h"
 #include "igloo.h"
 #include "signal_hc.h"
 #include "portal/portal.h"
diff --git a/src/hooks/sock_hc.c b/src/hooks/sock_hc.c
index 93ee2fb..a0c0a37 100644
--- a/src/hooks/sock_hc.c
+++ b/src/hooks/sock_hc.c
@@ -4,7 +4,7 @@
 #include <linux/mm.h>
 #include <linux/sched.h>
 #include <linux/slab.h>
-#include "hypercall.h"
+#include "igloo_hypercall.h"
 #include <linux/unistd.h>
 #include <linux/socket.h>
 #include <linux/ipv6.h>
diff --git a/src/hooks/syscalls_hc.c b/src/hooks/syscalls_hc.c
index da29f0e..52bf0b3 100644
--- a/src/hooks/syscalls_hc.c
+++ b/src/hooks/syscalls_hc.c
@@ -7,7 +7,7 @@
 #include <linux/slab.h>
 #include <linux/ftrace.h>
 #include <asm/ftrace.h>
-#include "hypercall.h" // Content is now included directly below
+#include "igloo_hypercall.h" // Content is now included directly below
 #include "igloo.h"
 #include <linux/binfmts.h>
 #include <linux/ptrace.h>
diff --git a/src/hooks/uname_hc.c b/src/hooks/uname_hc.c
index 55c7957..3233f19 100644
--- a/src/hooks/uname_hc.c
+++ b/src/hooks/uname_hc.c
@@ -5,7 +5,7 @@
 #include <linux/mm.h>
 #include <linux/sched.h>
 #include <linux/slab.h>
-#include "hypercall.h"
+#include "igloo_hypercall.h"
 #include "igloo.h"
 #include <linux/binfmts.h>
 #include <trace/syscall.h>
diff --git a/src/hyperfs/hyperfs.c b/src/hyperfs/hyperfs.c
index 675a6f0..b28d092 100644
--- a/src/hyperfs/hyperfs.c
+++ b/src/hyperfs/hyperfs.c
@@ -6,7 +6,7 @@
 #include <linux/parser.h>
 #include <linux/seq_file.h>
 #include <linux/slab.h>
-#include "hypercall.h"
+#include "igloo_hypercall.h"
 #include "portal/portal.h"
 // #include "../internal.h"
 #include "ioctl_hc.h"
diff --git a/src/igloo_hc.c b/src/igloo_hc.c
index 237047f..c6e17e6 100644
--- a/src/igloo_hc.c
+++ b/src/igloo_hc.c
@@ -11,7 +11,7 @@
 #include <linux/unistd.h>
 #include "syscalls_hc.h"
 #include "portal/portal.h"
-#include "hypercall.h"
+#include "igloo_hypercall.h"
 #include "igloo_hypercall_consts.h"
 #include "hyperfs/hyperfs.h"
 
diff --git a/src/igloo_hypercall.h b/src/igloo_hypercall.h
new file mode 100644
index 0000000..05e985f
--- /dev/null
+++ b/src/igloo_hypercall.h
@@ -0,0 +1,28 @@
+#ifndef IGLOO_DRIVER_HYPERCALL_H
+#define IGLOO_DRIVER_HYPERCALL_H
+
+#include <linux/types.h>
+#include "ehypercall.h"
+
+static inline unsigned long igloo_hypercall(unsigned long num,
+                                            unsigned long arg1)
+{
+    return igloo_hypercall4(num, arg1, 0, 0, 0);
+}
+
+static inline unsigned long igloo_hypercall2(unsigned long num,
+                                             unsigned long arg1,
+                                             unsigned long arg2)
+{
+    return igloo_hypercall4(num, arg1, arg2, 0, 0);
+}
+
+static inline unsigned long igloo_hypercall3(unsigned long num,
+                                             unsigned long arg1,
+                                             unsigned long arg2,
+                                             unsigned long arg3)
+{
+    return igloo_hypercall4(num, arg1, arg2, arg3, 0);
+}
+
+#endif
diff --git a/src/portal/portal_internal.h b/src/portal/portal_internal.h
index d75a35b..568a6d0 100644
--- a/src/portal/portal_internal.h
+++ b/src/portal/portal_internal.h
@@ -18,7 +18,7 @@
 #include <trace/syscall.h>
 #include <asm/syscall.h>
 #include <linux/printk.h>
-#include "hypercall.h"
+#include "igloo_hypercall.h"
 #include "igloo.h"
 #include "syscalls_hc.h"
 #include "igloo_debug.h"
diff --git a/src/portal/portal_procfs.c b/src/portal/portal_procfs.c
index f659679..f8d0070 100644
--- a/src/portal/portal_procfs.c
+++ b/src/portal/portal_procfs.c
@@ -301,7 +301,8 @@ igloo_convert_ops_to_proc_ops(const struct igloo_proc_ops *ops, struct proc_ops
     out->proc_get_unmapped_area = ops->get_unmapped_area;
     return out;
 }
-#else
+#endif
+
 static inline const struct file_operations *
 igloo_convert_ops_to_fops(const struct igloo_proc_ops *ops, struct file_operations *out)
 {
@@ -325,7 +326,6 @@ igloo_convert_ops_to_fops(const struct igloo_proc_ops *ops, struct file_operatio
     out->get_unmapped_area = ops->get_unmapped_area;
     return out;
 }
-#endif
 
 // Unified proc_create wrapper
 static struct proc_dir_entry *igloo_proc_create_data(const char *name, umode_t mode,
@@ -599,6 +599,18 @@ static struct portal_procfs_entry *find_pid_template(const char *parent, const c
         }
     }
     spin_unlock(&procfs_pid_template_lock);
+    if (entry)
+        return entry;
+
+    spin_lock(&procfs_pid_template_lock);
+    list_for_each_entry(tmpl, &procfs_pid_template_list, list) {
+        if (!strcmp(tmpl->parent, "*") &&
+            strlen(tmpl->name) == len && !memcmp(tmpl->name, name, len)) {
+            entry = tmpl->entry;
+            break;
+        }
+    }
+    spin_unlock(&procfs_pid_template_lock);
     return entry;
 }
 
@@ -769,6 +781,7 @@ void handle_op_procfs_create_file(portal_region *mem_region)
     int id;
     char *entry_name;
     bool exists, enable_default_mmap, synthetic_pid_parent = false;
+    const char *pid_template_key = NULL;
 
     req->path[PROCFS_MAX_PATH - 1] = '\0';
     entry_name = req->path;
@@ -780,35 +793,54 @@ void handle_op_procfs_create_file(portal_region *mem_region)
         goto out;
     }
 
-    // Parent must be provided (0 means root)
+    // Parent must be provided (0 means root, PROCFS_PID_PARENT_ID means /proc/<pid>)
     if (req->parent_id) {
-        parent_dir_struct = find_proc_dir_struct_by_id(req->parent_id);
-        if (!parent_dir_struct) {
-            printk(KERN_EMERG "portal_procfs: Invalid parent_id=%d for file '%s'\n", req->parent_id, entry_name);
-            mem_region->header.op = HYPER_RESP_WRITE_FAIL;
-            goto out;
-        }
-        synthetic_pid_parent = parent_dir_struct->synthetic_pid;
-        if (synthetic_pid_parent) {
+        if (req->parent_id == PROCFS_PID_PARENT_ID) {
             parent = ensure_pid_template_parent();
             if (!parent) {
                 printk(KERN_EMERG "portal_procfs: Failed to create pid template parent for '%s'\n", entry_name);
                 mem_region->header.op = HYPER_RESP_WRITE_FAIL;
                 goto out;
             }
+            synthetic_pid_parent = true;
+            pid_template_key = "*";
         } else {
-            parent = parent_dir_struct->entry;
-            if (!parent) {
-                printk(KERN_EMERG "portal_procfs: Invalid empty parent_id=%d for file '%s'\n", req->parent_id, entry_name);
+            parent_dir_struct = find_proc_dir_struct_by_id(req->parent_id);
+            if (!parent_dir_struct) {
+                printk(KERN_EMERG "portal_procfs: Invalid parent_id=%d for file '%s'\n", req->parent_id, entry_name);
                 mem_region->header.op = HYPER_RESP_WRITE_FAIL;
                 goto out;
             }
+            synthetic_pid_parent = parent_dir_struct->synthetic_pid;
+            if (synthetic_pid_parent) {
+                parent = ensure_pid_template_parent();
+                if (!parent) {
+                    printk(KERN_EMERG "portal_procfs: Failed to create pid template parent for '%s'\n", entry_name);
+                    mem_region->header.op = HYPER_RESP_WRITE_FAIL;
+                    goto out;
+                }
+            } else {
+                parent = parent_dir_struct->entry;
+                if (!parent) {
+                    printk(KERN_EMERG "portal_procfs: Invalid empty parent_id=%d for file '%s'\n", req->parent_id, entry_name);
+                    mem_region->header.op = HYPER_RESP_WRITE_FAIL;
+                    goto out;
+                }
+            }
+            if (synthetic_pid_parent)
+                pid_template_key = parent_dir_struct->path;
         }
     }
 
-    // Safety: Fetch the entry to check its type
-    existing = find_proc_subdir_entry(parent, entry_name);
-    exists = (existing != NULL);
+    // Safety: Fetch the entry to check its type. PID-relative entries are
+    // resolved by proc_tgid_base_lookup, not the root procfs rb-tree.
+    if (req->parent_id == PROCFS_PID_PARENT_ID) {
+        existing = NULL;
+        exists = false;
+    } else {
+        existing = find_proc_subdir_entry(parent, entry_name);
+        exists = (existing != NULL);
+    }
 
     // printk(KERN_EMERG "portal_procfs: parent=%p, entry_name='%s'\n", parent, entry_name);
 
@@ -872,8 +904,8 @@ void handle_op_procfs_create_file(portal_region *mem_region)
     list_add(&pe->list, &procfs_entry_list);
     spin_unlock(&procfs_entry_lock);
 
-    if (synthetic_pid_parent)
-        remember_pid_template(parent_dir_struct->path, entry_name, pe);
+    if (synthetic_pid_parent && pid_template_key)
+        remember_pid_template(pid_template_key, entry_name, pe);
 
     // printk(KERN_EMERG "portal_procfs: Created procfs entry '%s' with id %d\n", entry_name, id);
 
diff --git a/src/portal/portal_types.h b/src/portal/portal_types.h
index 59b73f3..4304412 100644
--- a/src/portal/portal_types.h
+++ b/src/portal/portal_types.h
@@ -126,6 +126,7 @@ struct portal_hyperfs_add_hyperfile_args {
 
 
 #define PROCFS_MAX_PATH 256
+#define PROCFS_PID_PARENT_ID -1
 
 // Universal proc ops struct
 struct igloo_proc_ops {