Fix deadlock on thread->times_update in getrusage()

Set thread->in_kernel properly on exiting interrupt handler when entering
it from kernel mode.

Conflicts:
	arch/x86_64/kernel/cpu.c
	kernel/mem.c

kernel/mem.c

@@ -1225,7 +1225,7 @@ out:
 		check_need_resched();
 		check_signal(0, regs, 0);
 	}
-	set_cputime(0);
+	set_cputime(interrupt_from_user(regs)? 0: 1);
 #ifdef PROFILE_ENABLE
 	if (thread->profile)
 		profile_event_add(PROFILE_page_fault, (rdtsc() - t_s));

kernel/process.c

@@ -407,6 +407,9 @@ clone_thread(struct thread *org, unsigned long pc, unsigned long sp,
 	ihk_atomic_set(&thread->refcount, 2);
 	memcpy(&thread->cpu_set, &org->cpu_set, sizeof(thread->cpu_set));
 
+	/* New thread is in kernel until jumping to enter_user_mode */
+	thread->in_kernel = org->in_kernel;
+
 	/* NOTE: sp is the user mode stack! */
 	ihk_mc_init_user_process(&thread->ctx, &thread->uctx, ((char *)thread) +
 				 KERNEL_STACK_NR_PAGES * PAGE_SIZE, pc, sp);