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Date: Wed, 31 Mar 2010 22:05:55 +0100
From: Russell King <rmk@arm.linux.org.uk>
To: Yinghai Lu <yinghai@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>, Rabin Vincent <rabin@rab.in>,
       lkml <linux-kernel@vger.kernel.org>, hpa@zytor.com,
       penberg@cs.helsinki.fi, cl@linux-foundation.org,
       Benjamin Herrenschmidt <benh@kernel.crashing.org>,
       linux-arch@vger.kernel.org
Subject: Re: start_kernel(): bug: interrupts were enabled early
Message-ID: <20100331210555.GA17715@flint.arm.linux.org.uk>
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	Andrew Morton <akpm@linux-foundation.org>,
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	Benjamin Herrenschmidt <benh@kernel.crashing.org>,
	linux-arch@vger.kernel.org
References: <20100325194100.GA2364@debian> <20100331134048.da4e35a7.akpm@linux-foundation.org> <4BB3B4DB.7040904@kernel.org>
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On Wed, Mar 31, 2010 at 01:47:23PM -0700, Yinghai Lu wrote:
> On 03/31/2010 01:40 PM, Andrew Morton wrote:
> > We have two checks in start_kernel():
> > 
> > 	if (!irqs_disabled()) {
> > 		printk(KERN_WARNING "start_kernel(): bug: interrupts were "
> > 				"enabled *very* early, fixing it\n");
> > 		local_irq_disable();
> > 	}
> > 	rcu_init();
> > 	radix_tree_init();
> > 	/* init some links before init_ISA_irqs() */
> > 	early_irq_init();
> > 	init_IRQ();
> > 	prio_tree_init();
> > 	init_timers();
> > 	hrtimers_init();
> > 	softirq_init();
> > 	timekeeping_init();
> > 	time_init();
> > 	profile_init();
> > 	if (!irqs_disabled())
> > 		printk(KERN_CRIT "start_kernel(): bug: interrupts were "
> > 				 "enabled early\n");
> > 
> > perhaps the second one isn't needed?  Perhaps no architecture requires
> > that local interrupts be disabled across the above initialisations?
> 	
> spin_unlock_irq from arm is different from other archs?

We use the standard generic kernel implementation.  Is x86 different? ;)

-- 
Russell King
 Linux kernel    2.6 ARM Linux   - http://www.arm.linux.org.uk/
 maintainer of: