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From: Paolo Bonzini <pbonzini@redhat.com>
To: Sandhya Kumar <insatiablecuriousity07@gmail.com>
Cc: qemu-devel@nongnu.org
Subject: Re: [Qemu-devel] On x86 MMU modes
Date: Wed, 03 Jun 2015 10:22:46 +0200	[thread overview]
Message-ID: <556EB956.1080301@redhat.com> (raw)
In-Reply-To: <CAEqbB45NivDZt5cnVf7OGUc=g=gDQTsBhbP0kDT-vFCEsB6qLw@mail.gmail.com>



On 03/06/2015 10:07, Sandhya Kumar wrote:
> Thanks again. One more question.
> 
> On versions prior to the mentioned commit, is there any specific reason
> (in x86 source code of QEMU) to choose separate modes for address
> translations (of kernel and user mode)? Or was that done just for
> performance improvement?

It's because pages can be accessible only from kernel space, so the
protection bits for the pages can be different in the two TLBs.

Paolo

  reply	other threads:[~2015-06-03  8:22 UTC|newest]

Thread overview: 11+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2015-06-03  6:51 [Qemu-devel] On x86 MMU modes Sandhya Kumar
2015-06-03  7:01 ` Paolo Bonzini
2015-06-03  7:41   ` Sandhya Kumar
2015-06-03  7:58     ` Paolo Bonzini
2015-06-03  8:07       ` Sandhya Kumar
2015-06-03  8:22         ` Paolo Bonzini [this message]
2015-06-03  9:24           ` Sandhya Kumar
2015-06-03  9:36             ` Peter Maydell
2015-06-06  7:36               ` Sandhya Kumar
2015-06-06 22:34                 ` Peter Maydell
2015-06-08  2:51                   ` Sandhya Kumar

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