All of lore.kernel.org
 help / color / mirror / Atom feed
From: Haibo Xu <haibo.xu@linaro.org>
To: Marc Zyngier <maz@kernel.org>
Cc: Steven Price <steven.price@arm.com>,
	Andrew Jones <drjones@redhat.com>,
	Catalin Marinas <catalin.marinas@arm.com>,
	Juan Quintela <quintela@redhat.com>,
	Richard Henderson <richard.henderson@linaro.org>,
	QEMU Developers <qemu-devel@nongnu.org>,
	"Dr. David Alan Gilbert" <dgilbert@redhat.com>,
	arm-mail-list <linux-arm-kernel@lists.infradead.org>,
	kvmarm <kvmarm@lists.cs.columbia.edu>,
	Thomas Gleixner <tglx@linutronix.de>,
	Will Deacon <will@kernel.org>, Dave Martin <Dave.Martin@arm.com>,
	lkml - Kernel Mailing List <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH v5 0/2] MTE support for KVM guest
Date: Tue, 8 Dec 2020 18:10:51 +0800	[thread overview]
Message-ID: <CAJc+Z1EafkLezXv=+1aPbaXo9uWpcB77iM32M70oyP6zEzacjw@mail.gmail.com> (raw)
In-Reply-To: <b77efceaec433dd98fdf2cd535a9cf40@kernel.org>

On Tue, 8 Dec 2020 at 18:01, Marc Zyngier <maz@kernel.org> wrote:
>
> On 2020-12-08 09:51, Haibo Xu wrote:
> > On Mon, 7 Dec 2020 at 22:48, Steven Price <steven.price@arm.com> wrote:
> >>
>
> [...]
>
> >> Sounds like you are making good progress - thanks for the update. Have
> >> you thought about how the PROT_MTE mappings might work if QEMU itself
> >> were to use MTE? My worry is that we end up with MTE in a guest
> >> preventing QEMU from using MTE itself (because of the PROT_MTE
> >> mappings). I'm hoping QEMU can wrap its use of guest memory in a
> >> sequence which disables tag checking (something similar will be needed
> >> for the "protected VM" use case anyway), but this isn't something I've
> >> looked into.
> >
> > As far as I can see, to map all the guest memory with PROT_MTE in VMM
> > is a little weird, and lots of APIs have to be changed to include this
> > flag.
> > IMHO, it would be better if the KVM can provide new APIs to load/store
> > the
> > guest memory tag which may make it easier to enable the Qemu migration
> > support.
>
> On what granularity? To what storage? How do you plan to synchronise
> this
> with the dirty-log interface?

The Qemu would migrate page by page, and if one page has been migrated but
becomes dirty again, the migration process would re-send this dirty page.
The current MTE migration POC codes would try to send the page tags just after
the page data, if one page becomes dirty again, the page data and the tags would
be re-sent.

>
> Thanks,
>
>          M.
> --
> Jazz is not dead. It just smells funny...

WARNING: multiple messages have this Message-ID (diff)
From: Haibo Xu <haibo.xu@linaro.org>
To: Marc Zyngier <maz@kernel.org>
Cc: Andrew Jones <drjones@redhat.com>,
	lkml - Kernel Mailing List <linux-kernel@vger.kernel.org>,
	Juan Quintela <quintela@redhat.com>,
	Catalin Marinas <catalin.marinas@arm.com>,
	Richard Henderson <richard.henderson@linaro.org>,
	QEMU Developers <qemu-devel@nongnu.org>,
	Steven Price <steven.price@arm.com>,
	arm-mail-list <linux-arm-kernel@lists.infradead.org>,
	Thomas Gleixner <tglx@linutronix.de>,
	Will Deacon <will@kernel.org>,
	kvmarm <kvmarm@lists.cs.columbia.edu>,
	"Dr. David Alan Gilbert" <dgilbert@redhat.com>,
	Dave Martin <Dave.Martin@arm.com>
Subject: Re: [PATCH v5 0/2] MTE support for KVM guest
Date: Tue, 8 Dec 2020 18:10:51 +0800	[thread overview]
Message-ID: <CAJc+Z1EafkLezXv=+1aPbaXo9uWpcB77iM32M70oyP6zEzacjw@mail.gmail.com> (raw)
In-Reply-To: <b77efceaec433dd98fdf2cd535a9cf40@kernel.org>

On Tue, 8 Dec 2020 at 18:01, Marc Zyngier <maz@kernel.org> wrote:
>
> On 2020-12-08 09:51, Haibo Xu wrote:
> > On Mon, 7 Dec 2020 at 22:48, Steven Price <steven.price@arm.com> wrote:
> >>
>
> [...]
>
> >> Sounds like you are making good progress - thanks for the update. Have
> >> you thought about how the PROT_MTE mappings might work if QEMU itself
> >> were to use MTE? My worry is that we end up with MTE in a guest
> >> preventing QEMU from using MTE itself (because of the PROT_MTE
> >> mappings). I'm hoping QEMU can wrap its use of guest memory in a
> >> sequence which disables tag checking (something similar will be needed
> >> for the "protected VM" use case anyway), but this isn't something I've
> >> looked into.
> >
> > As far as I can see, to map all the guest memory with PROT_MTE in VMM
> > is a little weird, and lots of APIs have to be changed to include this
> > flag.
> > IMHO, it would be better if the KVM can provide new APIs to load/store
> > the
> > guest memory tag which may make it easier to enable the Qemu migration
> > support.
>
> On what granularity? To what storage? How do you plan to synchronise
> this
> with the dirty-log interface?

The Qemu would migrate page by page, and if one page has been migrated but
becomes dirty again, the migration process would re-send this dirty page.
The current MTE migration POC codes would try to send the page tags just after
the page data, if one page becomes dirty again, the page data and the tags would
be re-sent.

>
> Thanks,
>
>          M.
> --
> Jazz is not dead. It just smells funny...


WARNING: multiple messages have this Message-ID (diff)
From: Haibo Xu <haibo.xu@linaro.org>
To: Marc Zyngier <maz@kernel.org>
Cc: lkml - Kernel Mailing List <linux-kernel@vger.kernel.org>,
	Juan Quintela <quintela@redhat.com>,
	Catalin Marinas <catalin.marinas@arm.com>,
	Richard Henderson <richard.henderson@linaro.org>,
	QEMU Developers <qemu-devel@nongnu.org>,
	Steven Price <steven.price@arm.com>,
	arm-mail-list <linux-arm-kernel@lists.infradead.org>,
	Thomas Gleixner <tglx@linutronix.de>,
	Will Deacon <will@kernel.org>,
	kvmarm <kvmarm@lists.cs.columbia.edu>,
	"Dr. David Alan Gilbert" <dgilbert@redhat.com>,
	Dave Martin <Dave.Martin@arm.com>
Subject: Re: [PATCH v5 0/2] MTE support for KVM guest
Date: Tue, 8 Dec 2020 18:10:51 +0800	[thread overview]
Message-ID: <CAJc+Z1EafkLezXv=+1aPbaXo9uWpcB77iM32M70oyP6zEzacjw@mail.gmail.com> (raw)
In-Reply-To: <b77efceaec433dd98fdf2cd535a9cf40@kernel.org>

On Tue, 8 Dec 2020 at 18:01, Marc Zyngier <maz@kernel.org> wrote:
>
> On 2020-12-08 09:51, Haibo Xu wrote:
> > On Mon, 7 Dec 2020 at 22:48, Steven Price <steven.price@arm.com> wrote:
> >>
>
> [...]
>
> >> Sounds like you are making good progress - thanks for the update. Have
> >> you thought about how the PROT_MTE mappings might work if QEMU itself
> >> were to use MTE? My worry is that we end up with MTE in a guest
> >> preventing QEMU from using MTE itself (because of the PROT_MTE
> >> mappings). I'm hoping QEMU can wrap its use of guest memory in a
> >> sequence which disables tag checking (something similar will be needed
> >> for the "protected VM" use case anyway), but this isn't something I've
> >> looked into.
> >
> > As far as I can see, to map all the guest memory with PROT_MTE in VMM
> > is a little weird, and lots of APIs have to be changed to include this
> > flag.
> > IMHO, it would be better if the KVM can provide new APIs to load/store
> > the
> > guest memory tag which may make it easier to enable the Qemu migration
> > support.
>
> On what granularity? To what storage? How do you plan to synchronise
> this
> with the dirty-log interface?

The Qemu would migrate page by page, and if one page has been migrated but
becomes dirty again, the migration process would re-send this dirty page.
The current MTE migration POC codes would try to send the page tags just after
the page data, if one page becomes dirty again, the page data and the tags would
be re-sent.

>
> Thanks,
>
>          M.
> --
> Jazz is not dead. It just smells funny...
_______________________________________________
kvmarm mailing list
kvmarm@lists.cs.columbia.edu
https://lists.cs.columbia.edu/mailman/listinfo/kvmarm

WARNING: multiple messages have this Message-ID (diff)
From: Haibo Xu <haibo.xu@linaro.org>
To: Marc Zyngier <maz@kernel.org>
Cc: Andrew Jones <drjones@redhat.com>,
	lkml - Kernel Mailing List <linux-kernel@vger.kernel.org>,
	Juan Quintela <quintela@redhat.com>,
	Catalin Marinas <catalin.marinas@arm.com>,
	Richard Henderson <richard.henderson@linaro.org>,
	QEMU Developers <qemu-devel@nongnu.org>,
	Steven Price <steven.price@arm.com>,
	arm-mail-list <linux-arm-kernel@lists.infradead.org>,
	Thomas Gleixner <tglx@linutronix.de>,
	Will Deacon <will@kernel.org>,
	kvmarm <kvmarm@lists.cs.columbia.edu>,
	"Dr. David Alan Gilbert" <dgilbert@redhat.com>,
	Dave Martin <Dave.Martin@arm.com>
Subject: Re: [PATCH v5 0/2] MTE support for KVM guest
Date: Tue, 8 Dec 2020 18:10:51 +0800	[thread overview]
Message-ID: <CAJc+Z1EafkLezXv=+1aPbaXo9uWpcB77iM32M70oyP6zEzacjw@mail.gmail.com> (raw)
In-Reply-To: <b77efceaec433dd98fdf2cd535a9cf40@kernel.org>

On Tue, 8 Dec 2020 at 18:01, Marc Zyngier <maz@kernel.org> wrote:
>
> On 2020-12-08 09:51, Haibo Xu wrote:
> > On Mon, 7 Dec 2020 at 22:48, Steven Price <steven.price@arm.com> wrote:
> >>
>
> [...]
>
> >> Sounds like you are making good progress - thanks for the update. Have
> >> you thought about how the PROT_MTE mappings might work if QEMU itself
> >> were to use MTE? My worry is that we end up with MTE in a guest
> >> preventing QEMU from using MTE itself (because of the PROT_MTE
> >> mappings). I'm hoping QEMU can wrap its use of guest memory in a
> >> sequence which disables tag checking (something similar will be needed
> >> for the "protected VM" use case anyway), but this isn't something I've
> >> looked into.
> >
> > As far as I can see, to map all the guest memory with PROT_MTE in VMM
> > is a little weird, and lots of APIs have to be changed to include this
> > flag.
> > IMHO, it would be better if the KVM can provide new APIs to load/store
> > the
> > guest memory tag which may make it easier to enable the Qemu migration
> > support.
>
> On what granularity? To what storage? How do you plan to synchronise
> this
> with the dirty-log interface?

The Qemu would migrate page by page, and if one page has been migrated but
becomes dirty again, the migration process would re-send this dirty page.
The current MTE migration POC codes would try to send the page tags just after
the page data, if one page becomes dirty again, the page data and the tags would
be re-sent.

>
> Thanks,
>
>          M.
> --
> Jazz is not dead. It just smells funny...

_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

  reply	other threads:[~2020-12-08 10:11 UTC|newest]

Thread overview: 152+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-11-19 15:38 [PATCH v5 0/2] MTE support for KVM guest Steven Price
2020-11-19 15:38 ` Steven Price
2020-11-19 15:38 ` Steven Price
2020-11-19 15:38 ` Steven Price
2020-11-19 15:39 ` [PATCH v5 1/2] arm64: kvm: Save/restore MTE registers Steven Price
2020-11-19 15:39   ` Steven Price
2020-11-19 15:39   ` Steven Price
2020-11-19 15:39   ` Steven Price
2020-11-19 15:39 ` [PATCH v5 2/2] arm64: kvm: Introduce MTE VCPU feature Steven Price
2020-11-19 15:39   ` Steven Price
2020-11-19 15:39   ` Steven Price
2020-11-19 15:39   ` Steven Price
2020-11-19 15:45 ` [PATCH v5 0/2] MTE support for KVM guest Peter Maydell
2020-11-19 15:45   ` Peter Maydell
2020-11-19 15:45   ` Peter Maydell
2020-11-19 15:45   ` Peter Maydell
2020-11-19 15:57   ` Steven Price
2020-11-19 15:57     ` Steven Price
2020-11-19 15:57     ` Steven Price
2020-11-19 15:57     ` Steven Price
2020-11-19 16:39     ` Peter Maydell
2020-11-19 16:39       ` Peter Maydell
2020-11-19 16:39       ` Peter Maydell
2020-11-19 16:39       ` Peter Maydell
2020-11-19 18:42   ` Andrew Jones
2020-11-19 18:42     ` Andrew Jones
2020-11-19 18:42     ` Andrew Jones
2020-11-19 18:42     ` Andrew Jones
2020-11-19 19:11     ` Marc Zyngier
2020-11-19 19:11       ` Marc Zyngier
2020-11-19 19:11       ` Marc Zyngier
2020-11-19 19:11       ` Marc Zyngier
2020-11-20  9:50       ` Steven Price
2020-11-20  9:50         ` Steven Price
2020-11-20  9:50         ` Steven Price
2020-11-20  9:50         ` Steven Price
2020-11-20  9:56         ` Marc Zyngier
2020-11-20  9:56           ` Marc Zyngier
2020-11-20  9:56           ` Marc Zyngier
2020-11-20  9:56           ` Marc Zyngier
2020-11-20  9:58           ` Steven Price
2020-11-20  9:58             ` Steven Price
2020-11-20  9:58             ` Steven Price
2020-11-20  9:58             ` Steven Price
2020-12-04  8:25         ` Haibo Xu
2020-12-04  8:25           ` Haibo Xu
2020-12-04  8:25           ` Haibo Xu
2020-12-04  8:25           ` Haibo Xu
2020-12-07 14:48           ` Steven Price
2020-12-07 14:48             ` Steven Price
2020-12-07 14:48             ` Steven Price
2020-12-07 14:48             ` Steven Price
2020-12-07 15:27             ` Peter Maydell
2020-12-07 15:27               ` Peter Maydell
2020-12-07 15:27               ` Peter Maydell
2020-12-07 15:27               ` Peter Maydell
2020-12-07 15:45               ` Steven Price
2020-12-07 15:45                 ` Steven Price
2020-12-07 15:45                 ` Steven Price
2020-12-07 15:45                 ` Steven Price
2020-12-07 16:05                 ` Marc Zyngier
2020-12-07 16:05                   ` Marc Zyngier
2020-12-07 16:05                   ` Marc Zyngier
2020-12-07 16:05                   ` Marc Zyngier
2020-12-07 16:34                   ` Catalin Marinas
2020-12-07 16:34                     ` Catalin Marinas
2020-12-07 16:34                     ` Catalin Marinas
2020-12-07 16:34                     ` Catalin Marinas
2020-12-07 19:03                     ` Marc Zyngier
2020-12-07 19:03                       ` Marc Zyngier
2020-12-07 19:03                       ` Marc Zyngier
2020-12-07 19:03                       ` Marc Zyngier
2020-12-08 17:21                       ` Catalin Marinas
2020-12-08 17:21                         ` Catalin Marinas
2020-12-08 17:21                         ` Catalin Marinas
2020-12-08 17:21                         ` Catalin Marinas
2020-12-08 18:21                         ` Marc Zyngier
2020-12-08 18:21                           ` Marc Zyngier
2020-12-08 18:21                           ` Marc Zyngier
2020-12-08 18:21                           ` Marc Zyngier
2020-12-09 12:44                           ` Catalin Marinas
2020-12-09 12:44                             ` Catalin Marinas
2020-12-09 12:44                             ` Catalin Marinas
2020-12-09 12:44                             ` Catalin Marinas
2020-12-09 13:25                             ` Marc Zyngier
2020-12-09 13:25                               ` Marc Zyngier
2020-12-09 13:25                               ` Marc Zyngier
2020-12-09 13:25                               ` Marc Zyngier
2020-12-09 15:27                               ` Catalin Marinas
2020-12-09 15:27                                 ` Catalin Marinas
2020-12-09 15:27                                 ` Catalin Marinas
2020-12-09 15:27                                 ` Catalin Marinas
2020-12-09 18:27                                 ` Richard Henderson
2020-12-09 18:27                                   ` Richard Henderson
2020-12-09 18:27                                   ` Richard Henderson
2020-12-09 18:27                                   ` Richard Henderson
2020-12-09 18:39                                   ` Catalin Marinas
2020-12-09 18:39                                     ` Catalin Marinas
2020-12-09 18:39                                     ` Catalin Marinas
2020-12-09 18:39                                     ` Catalin Marinas
2020-12-09 20:13                                     ` Richard Henderson
2020-12-09 20:13                                       ` Richard Henderson
2020-12-09 20:13                                       ` Richard Henderson
2020-12-09 20:13                                       ` Richard Henderson
2020-12-09 20:20                                       ` Peter Maydell
2020-12-09 20:20                                         ` Peter Maydell
2020-12-09 20:20                                         ` Peter Maydell
2020-12-09 20:20                                         ` Peter Maydell
2020-12-07 16:44                 ` Dr. David Alan Gilbert
2020-12-07 16:44                   ` Dr. David Alan Gilbert
2020-12-07 16:44                   ` Dr. David Alan Gilbert
2020-12-07 16:44                   ` Dr. David Alan Gilbert
2020-12-07 17:10                   ` Peter Maydell
2020-12-07 17:10                     ` Peter Maydell
2020-12-07 17:10                     ` Peter Maydell
2020-12-07 17:10                     ` Peter Maydell
2020-12-07 17:44                     ` Dr. David Alan Gilbert
2020-12-07 17:44                       ` Dr. David Alan Gilbert
2020-12-07 17:44                       ` Dr. David Alan Gilbert
2020-12-07 17:44                       ` Dr. David Alan Gilbert
2020-12-08 10:05                   ` Haibo Xu
2020-12-08 10:05                     ` Haibo Xu
2020-12-08 10:05                     ` Haibo Xu
2020-12-08 10:05                     ` Haibo Xu
2020-12-08  9:51             ` Haibo Xu
2020-12-08  9:51               ` Haibo Xu
2020-12-08  9:51               ` Haibo Xu
2020-12-08  9:51               ` Haibo Xu
2020-12-08 10:01               ` Marc Zyngier
2020-12-08 10:01                 ` Marc Zyngier
2020-12-08 10:01                 ` Marc Zyngier
2020-12-08 10:01                 ` Marc Zyngier
2020-12-08 10:10                 ` Haibo Xu [this message]
2020-12-08 10:10                   ` Haibo Xu
2020-12-08 10:10                   ` Haibo Xu
2020-12-08 10:10                   ` Haibo Xu
2020-12-16  7:31             ` Haibo Xu
2020-12-16  7:31               ` Haibo Xu
2020-12-16  7:31               ` Haibo Xu
2020-12-16  7:31               ` Haibo Xu
2020-12-16 10:22               ` Steven Price
2020-12-16 10:22                 ` Steven Price
2020-12-16 10:22                 ` Steven Price
2020-12-16 10:22                 ` Steven Price
2020-12-17  1:47                 ` Haibo Xu
2020-12-17  1:47                   ` Haibo Xu
2020-12-17  1:47                   ` Haibo Xu
2020-12-17  1:47                   ` Haibo Xu
2020-11-23 12:16   ` Dr. David Alan Gilbert
2020-11-23 12:16     ` Dr. David Alan Gilbert
2020-11-23 12:16     ` Dr. David Alan Gilbert
2020-11-23 12:16     ` Dr. David Alan Gilbert

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='CAJc+Z1EafkLezXv=+1aPbaXo9uWpcB77iM32M70oyP6zEzacjw@mail.gmail.com' \
    --to=haibo.xu@linaro.org \
    --cc=Dave.Martin@arm.com \
    --cc=catalin.marinas@arm.com \
    --cc=dgilbert@redhat.com \
    --cc=drjones@redhat.com \
    --cc=kvmarm@lists.cs.columbia.edu \
    --cc=linux-arm-kernel@lists.infradead.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=maz@kernel.org \
    --cc=qemu-devel@nongnu.org \
    --cc=quintela@redhat.com \
    --cc=richard.henderson@linaro.org \
    --cc=steven.price@arm.com \
    --cc=tglx@linutronix.de \
    --cc=will@kernel.org \
    /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.