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Subject: Re: Rethinking sigcontext's xfeatures slightly for PKRU's benefit?
To: Andy Lutomirski <luto@amacapital.net>, "H. Peter Anvin" <hpa@zytor.com>
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Cc: Oleg Nesterov <oleg@redhat.com>, Thomas Gleixner <tglx@linutronix.de>,
        Ingo Molnar <mingo@kernel.org>, Borislav Petkov <bp@alien8.de>,
        Brian Gerst <brgerst@gmail.com>,
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        Linus Torvalds <torvalds@linux-foundation.org>,
        Christoph Hellwig <hch@lst.de>
From: Dave Hansen <dave.hansen@linux.intel.com>
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Date: Fri, 18 Dec 2015 08:56:51 -0800
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On 12/18/2015 08:04 AM, Andy Lutomirski wrote:
> Which reminds me: __get_user, etc all respect PKRU because the SDM
> says that PKRU affects all user *and* kernel accesses to user memory
> (i.e. anything with _PAGE_USER).  Should get_user_pages also respect
> PKRU?

It does.  There are a couple of parts to it, but the most important are
in these patches:

> http://git.kernel.org/cgit/linux/kernel/git/daveh/x86-pkeys.git/commit/?h=pkeys-v018&id=c64acbe036487d07968ea6a5b9090169d6e40160
> http://git.kernel.org/cgit/linux/kernel/git/daveh/x86-pkeys.git/commit/?h=pkeys-v018&id=331c62eb789f969e187964e28ac80b1e0e26b69d