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Message-ID: <48DBD8A6.8060900@ct.jp.nec.com>
Date: Thu, 25 Sep 2008 11:29:58 -0700
From: Hiroshi Shimamoto <h-shimamoto@ct.jp.nec.com>
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To: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@elte.hu>, Thomas Gleixner <tglx@linutronix.de>,
       linux-kernel@vger.kernel.org
Subject: Re: [RFC PATCH v2 -tip 0/4] x86: signal handler improvement
References: <48DBD396.5020103@ct.jp.nec.com> <48DBD519.6030204@zytor.com>
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H. Peter Anvin wrote:
> Hiroshi Shimamoto wrote:
>> and errors in __put_user is stored to stack.
>> At the end of function, all errors in stack are calculated. If access to user
>> space is failed, %edx is set to -EFAULT in exception handler and stored to
>> stack for later operation.
>> It seems inefficient.
>>
> 
> This is a gcc failure, and should be reported to the gcc people.

Does this gcc failure mean unnecessary storing into stack?

thanks,
Hiroshi Shimamoto