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Date: Mon, 11 Nov 2013 20:34:31 +0100 (CET)
From: Thomas Gleixner <tglx@linutronix.de>
To: Geert Uytterhoeven <geert@linux-m68k.org>
cc: Michael Schmitz <schmitz@biophys.uni-duesseldorf.de>,
        LKML <linux-kernel@vger.kernel.org>,
        Linux/m68k <linux-m68k@vger.kernel.org>
Subject: Re: [patch 1/6] hardirq: Make hardirq bits generic
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On Mon, 11 Nov 2013, Thomas Gleixner wrote:
> Not what you would expect, right?

Finally found the issue. The patch below fixes the problem here. The
little missing detail is, that I zapped GET_CURRENT() assuming blindly
that this is only needed for the preempt_count hackery. But in fact
the world and some more depends on it which leads to interesting
explosions.

Thanks,

	tglx
----
Index: linux-2.6/arch/m68k/kernel/entry.S
===================================================================
--- linux-2.6.orig/arch/m68k/kernel/entry.S
+++ linux-2.6/arch/m68k/kernel/entry.S
@@ -274,6 +274,7 @@ do_delayed_trace:
 
 ENTRY(auto_inthandler)
 	SAVE_ALL_INT
+	GET_CURRENT(%d0)
 					|  put exception # in d0
 	bfextu	%sp@(PT_OFF_FORMATVEC){#4,#10},%d0
 	subw	#VEC_SPUR,%d0
@@ -297,6 +298,7 @@ ret_from_interrupt:
 
 ENTRY(user_inthandler)
 	SAVE_ALL_INT
+	GET_CURRENT(%d0)
 					|  put exception # in d0
 	bfextu	%sp@(PT_OFF_FORMATVEC){#4,#10},%d0
 user_irqvec_fixup = . + 2
@@ -313,6 +315,7 @@ user_irqvec_fixup = . + 2
 
 ENTRY(bad_inthandler)
 	SAVE_ALL_INT
+	GET_CURRENT(%d0)
 
 	movel	%sp,%sp@-
 	jsr	handle_badint