From mboxrd@z Thu Jan  1 00:00:00 1970
From: Cong Wang <amwang@redhat.com>
Subject: Re: [PATCH 14/15] netpoll: re-enable irq in poll_napi()
Date: Sat, 25 Aug 2012 14:28:40 +0800
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Cc: netdev@vger.kernel.org, David Miller <davem@davemloft.net>
To: Andrew Morton <akpm@linux-foundation.org>
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On Fri, 2012-08-24 at 12:43 -0700, Andrew Morton wrote:
> 
> This commit (6bdb7fe3104 in mainline) makes my netconsole-using x86_64
> box lock up during boot.  Dunno why, but I do have a cellphone:
> http://ozlabs.org/~akpm/stuff/IMG_20120824_122054.jpg
> 

Thanks for the report!

Sylvain reported a CPU stall problem which is probably caused by this
commit too.

This commit is to fix another issue, that is, we call be_process_mcc()
which calls spin_lock_bh() with IRQ disabled, this leads to a warning
in:

static inline void _local_bh_enable_ip(unsigned long ip)
{
        WARN_ON_ONCE(in_irq() || irqs_disabled());
	...
}

I think I should just fix be_process_mcc(), instead of re-enabling IRO
for all ->poll callbacks.

I will send a patch to David soon.