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From: Roland McGrath <roland@redhat.com>
To: bryan.wu@analog.com
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Cc: David Howells <dhowells@redhat.com>,
       Andrew Morton <akpm@linux-foundation.org>, linux-kernel@vger.kernel.org
Subject: Re: [PATCH -mm] utrace: nommu fixup support utrace
In-Reply-To: Wu, Bryan's message of  Tuesday, 6 March 2007 15:25:27 +0800 <1173165927.17134.5.camel@roc-desktop>
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Date: Tue,  6 Mar 2007 19:42:16 -0800 (PST)
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That old ptrace check seems pretty questionable to me.  I think what you
want is for the nommu world's get_user_pages/access_process_vm when called
with force=1,write=1 on a read-only MAP_PRIVATE page to do something more
morally similar to the mmu world's COW than it does now.


Thanks,
Roland