qemu-devel.nongnu.org archive mirror
 help / color / mirror / Atom feed
From: Paolo Bonzini <pbonzini@redhat.com>
To: "Dr. David Alan Gilbert" <dgilbert@redhat.com>,
	Igor Mammedov <imammedo@redhat.com>
Cc: peter.maydell@linaro.org, qemu-stable@nongnu.org,
	lersek@redhat.com, qemu-devel@nongnu.org, mst@redhat.com
Subject: Re: [Qemu-devel] [PATCH for-2.1 2/2] acpi: mark ACPI tables ROM blob as extend-able on migration
Date: Tue, 04 Nov 2014 17:30:14 +0100	[thread overview]
Message-ID: <5458FF16.6050201@redhat.com> (raw)
In-Reply-To: <20141103173627.GC29967@work-vm>

On 03/11/2014 18:36, Dr. David Alan Gilbert wrote:
>   1) It's a block of data that's never mapped into the guests address
> space
>   2) It can change, but only at guest reset
>   3) Worst case is it can get upto about 2MB in size
> 
> it's pretty marginal whether this thing should be a RAMBlock,
> it doesn't feel like normal RAM or ROM in most ways; but there
> again 2MB is getting a bit large for the device state; hmm.

And also I think changing migration format gratuitously is bad.  We
decided to make these RAMs, which has some advantages and turned out to
have some possible disadvantages, but it's not a big deal.  They are
some kind of EPROM if you wish.

The important point is that we can (and arguably _should_ since it keeps
us honest!) make these ACPI tables RAMBlocks fixed-size per machine
type.  See the patches I posted around late September/early October.
There is no need to support auto-fixing of the RAMBlock's sizes.

Paolo

  reply	other threads:[~2014-11-04 16:30 UTC|newest]

Thread overview: 19+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2014-07-25 15:48 [Qemu-devel] [PATCH for-2.1 0/2] Fix migration failure due to ACPI tables size changes Igor Mammedov
2014-07-25 15:48 ` [Qemu-devel] [PATCH for-2.1 1/2] migration: load smaller RAMBlock to a bigger one if permitted Igor Mammedov
2014-07-25 17:56   ` Laszlo Ersek
2014-07-28  7:40     ` Igor Mammedov
2014-07-28  8:11       ` Laszlo Ersek
2014-07-25 15:48 ` [Qemu-devel] [PATCH for-2.1 2/2] acpi: mark ACPI tables ROM blob as extend-able on migration Igor Mammedov
2014-07-25 17:37   ` Paolo Bonzini
2014-07-28  7:56     ` Igor Mammedov
2014-07-28  8:16       ` Paolo Bonzini
2014-07-25 17:58   ` Laszlo Ersek
2014-11-03 17:36   ` Dr. David Alan Gilbert
2014-11-04 16:30     ` Paolo Bonzini [this message]
2014-11-04 16:46       ` Michael S. Tsirkin
2014-11-04 16:54         ` Paolo Bonzini
2014-11-04 17:25           ` Michael S. Tsirkin
2014-11-04 17:35             ` Paolo Bonzini
2014-11-04 17:42               ` Michael S. Tsirkin
2014-07-25 16:17 ` [Qemu-devel] [PATCH for-2.1 0/2] Fix migration failure due to ACPI tables size changes Laszlo Ersek
2014-07-26  7:03   ` Paolo Bonzini

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=5458FF16.6050201@redhat.com \
    --to=pbonzini@redhat.com \
    --cc=dgilbert@redhat.com \
    --cc=imammedo@redhat.com \
    --cc=lersek@redhat.com \
    --cc=mst@redhat.com \
    --cc=peter.maydell@linaro.org \
    --cc=qemu-devel@nongnu.org \
    --cc=qemu-stable@nongnu.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 a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).