From: Alexander Graf <agraf@suse.de>
To: Peter Maydell <peter.maydell@linaro.org>
Cc: Igor Mammedov <imammedo@redhat.com>,
kvm-devel <kvm@vger.kernel.org>,
QEMU Developers <qemu-devel@nongnu.org>,
qemu-stable <qemu-stable@nongnu.org>,
Stuart Yoder <stuart.yoder@freescale.com>,
"qemu-ppc@nongnu.org" <qemu-ppc@nongnu.org>,
Paolo Bonzini <pbonzini@redhat.com>
Subject: Re: [Qemu-devel] [PATCH] kvm: Fix memory slot page alignment logic
Date: Mon, 10 Nov 2014 15:48:54 +0100 [thread overview]
Message-ID: <5460D056.5010007@suse.de> (raw)
In-Reply-To: <CAFEAcA88fDLjnFRLUgxQLY+7-2bHuMJUxP7TtH5Ka-CWpPiPfw@mail.gmail.com>
On 10.11.14 14:55, Peter Maydell wrote:
> On 10 November 2014 13:16, Alexander Graf <agraf@suse.de> wrote:
>> Sorry, I don't understand this paragraph. Memory slots in general are
>> accelerations for memory access - for MMIO (RAM is usually aligned), KVM
>> can always exit to QEMU and just do a manual MMIO exit.
>
> ...you're a bit stuck if you were hoping to execute code from
> that RAM, though, so they're not *purely* acceleration, right?
Yes and no. Technically, there's no reason KVM couldn't do an MMIO exit
dance to fetch the next instruction. From user space this should be
indistinguishable.
Today, I don't think it's implemented though :).
Alex
WARNING: multiple messages have this Message-ID (diff)
From: Alexander Graf <agraf@suse.de>
To: Peter Maydell <peter.maydell@linaro.org>
Cc: kvm-devel <kvm@vger.kernel.org>,
qemu-stable <qemu-stable@nongnu.org>,
Stuart Yoder <stuart.yoder@freescale.com>,
QEMU Developers <qemu-devel@nongnu.org>,
"qemu-ppc@nongnu.org" <qemu-ppc@nongnu.org>,
Paolo Bonzini <pbonzini@redhat.com>,
Igor Mammedov <imammedo@redhat.com>
Subject: Re: [Qemu-devel] [PATCH] kvm: Fix memory slot page alignment logic
Date: Mon, 10 Nov 2014 15:48:54 +0100 [thread overview]
Message-ID: <5460D056.5010007@suse.de> (raw)
In-Reply-To: <CAFEAcA88fDLjnFRLUgxQLY+7-2bHuMJUxP7TtH5Ka-CWpPiPfw@mail.gmail.com>
On 10.11.14 14:55, Peter Maydell wrote:
> On 10 November 2014 13:16, Alexander Graf <agraf@suse.de> wrote:
>> Sorry, I don't understand this paragraph. Memory slots in general are
>> accelerations for memory access - for MMIO (RAM is usually aligned), KVM
>> can always exit to QEMU and just do a manual MMIO exit.
>
> ...you're a bit stuck if you were hoping to execute code from
> that RAM, though, so they're not *purely* acceleration, right?
Yes and no. Technically, there's no reason KVM couldn't do an MMIO exit
dance to fetch the next instruction. From user space this should be
indistinguishable.
Today, I don't think it's implemented though :).
Alex
next prev parent reply other threads:[~2014-11-10 14:48 UTC|newest]
Thread overview: 18+ messages / expand[flat|nested] mbox.gz Atom feed top
2014-11-07 21:18 [PATCH] kvm: Fix memory slot page alignment logic Alexander Graf
2014-11-07 21:18 ` [Qemu-devel] " Alexander Graf
2014-11-07 21:24 ` [Qemu-ppc] " Alexander Graf
2014-11-07 21:24 ` [Qemu-devel] " Alexander Graf
2014-11-10 12:31 ` Igor Mammedov
2014-11-10 12:31 ` [Qemu-devel] " Igor Mammedov
2014-11-10 13:16 ` Alexander Graf
2014-11-10 13:16 ` [Qemu-devel] " Alexander Graf
2014-11-10 13:54 ` Paolo Bonzini
2014-11-10 13:54 ` [Qemu-devel] " Paolo Bonzini
2014-11-10 13:55 ` Peter Maydell
2014-11-10 13:55 ` Peter Maydell
2014-11-10 14:48 ` Alexander Graf [this message]
2014-11-10 14:48 ` Alexander Graf
2014-11-10 13:55 ` Igor Mammedov
2014-11-10 13:55 ` [Qemu-devel] " Igor Mammedov
2014-11-10 14:47 ` Alexander Graf
2014-11-10 14:47 ` [Qemu-devel] " Alexander Graf
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=5460D056.5010007@suse.de \
--to=agraf@suse.de \
--cc=imammedo@redhat.com \
--cc=kvm@vger.kernel.org \
--cc=pbonzini@redhat.com \
--cc=peter.maydell@linaro.org \
--cc=qemu-devel@nongnu.org \
--cc=qemu-ppc@nongnu.org \
--cc=qemu-stable@nongnu.org \
--cc=stuart.yoder@freescale.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.