Index: uspace/lib/libc/arch/amd64/src/entry.s
===================================================================
--- uspace/lib/libc/arch/amd64/src/entry.s	(revision d51db079aa01ad329ce298e255b1840cd48189bb)
+++ uspace/lib/libc/arch/amd64/src/entry.s	(revision c98e6ee244a8e271a395a052069c23bca4f8b538)
@@ -35,7 +35,10 @@
 ## User-space task entry point
 #
+# %rdi contains the PCB pointer
 #
 __entry:
+	# %rdi was deliberately chosen as the first argument is also in %rdi
+	# Pass PCB pointer to __main (no operation)
 	call __main
-	call main
+
 	call __exit