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Date: Sat, 13 Feb 2010 10:29:35 +0200
From: Avi Kivity <avi@redhat.com>
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To: "H. Peter Anvin" <hpa@zytor.com>
CC: linux-kernel@vger.kernel.org
Subject: Re: [PATCH] x86-64, rwsem: Avoid store forwarding hazzard in __downgrade_write
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On 02/13/2010 10:16 AM, H. Peter Anvin wrote:
> On 02/12/2010 11:13 PM, Avi Kivity wrote:
>    
>> +#ifndef CONFIG_X86_64
>> +		       "i" (-RWSEM_WAITING_BIAS)
>> +#else
>> +		       "r" (-RWSEM_WAITING_BIAS)
>>   #endif
>> +		     : "memory", "cc");
>>      
> Using an "er" constraint here should work on both architectures.
>
>    

Right.  v2 to follow.

-- 
Do not meddle in the internals of kernels, for they are subtle and quick to panic.