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Subject: [PATCH] safty check of MAX_RT_PRIO >= MAX_USER_RT_PRIO
From: Steven Rostedt <rostedt@goodmis.org>
To: Ingo Molnar <mingo@elte.hu>
Cc: LKML <linux-kernel@vger.kernel.org>, Linus Torvalds <torvalds@osdl.org>,
       Andrew Morton <akpm@osdl.org>
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Organization: Kihon Technologies
Date: Wed, 27 Jul 2005 10:47:00 -0400
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On Wed, 2005-07-27 at 16:33 +0200, Ingo Molnar wrote:
> i'm not excluding that this will become necessary in the future. We 
> should also add the safety check to sched.h - all i'm suggesting is to 
> not make it a .config option just now, because that tends to be fiddled 
> with.

So Ingo, would you agree that at least this patch should go in?

-- Steve

(Patched against 2.6.12.2)

Index: vanilla_kernel/include/linux/sched.h
===================================================================
--- vanilla_kernel/include/linux/sched.h	(revision 263)
+++ vanilla_kernel/include/linux/sched.h	(working copy)
@@ -392,6 +392,10 @@
 #define MAX_USER_RT_PRIO	100
 #define MAX_RT_PRIO		MAX_USER_RT_PRIO
 
+#if MAX_USER_RT_PRIO > MAX_RT_PRIO
+#error MAX_USER_RT_PRIO must not be greater than MAX_RT_PRIO
+#endif
+
 #define MAX_PRIO		(MAX_RT_PRIO + 40)
 
 #define rt_task(p)		(unlikely((p)->prio < MAX_RT_PRIO))