[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: [Qemu-devel] [PATCH] q35: split memory at 2G
From: |
Eric Blake |
Subject: |
Re: [Qemu-devel] [PATCH] q35: split memory at 2G |
Date: |
Tue, 28 May 2019 15:58:25 -0500 |
User-agent: |
Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.6.1 |
On 5/28/19 3:48 PM, Gerd Hoffmann wrote:
> Original q35 behavior was to split memory 2.75 GB, leaving space for the
s/memory/memory at/
> mmconfig bar at 0xb000000 and pci I/O window starting at 0xc0000000.
>
> Note: Those machine types have been removed from the qemu codebase
> meanwhile because they could not be live-migrated so there was little
> value in keeping them around.
>
> With the effort to allow for gigabyte-alignment of guest memory that
> behavior was changed: The split was moved to 2G, but only in case the
> memory didn't fit below 2.75 GB.
>
> So today the address space between 2G and 2,75G is not used for guest
> memory in typical use cases, where the guest memory sized at a power of
s/memory/memory is/
> two or a gigabyte number. But if you configure your guest with some odd
> amout of memory (such as 2.5G) the address space is used.
s/amout/amount/
>
> This patch removes that oddity for 4.1+ machine types. The memory is
> splitted at 2G no matter what.
s/splitted/split/
>
> Cc: László Érsek <address@hidden>
> Signed-off-by: Gerd Hoffmann <address@hidden>
> ---
> include/hw/i386/pc.h | 1 +
> hw/i386/pc.c | 1 +
> hw/i386/pc_q35.c | 7 ++++++-
> 3 files changed, 8 insertions(+), 1 deletion(-)
>
--
Eric Blake, Principal Software Engineer
Red Hat, Inc. +1-919-301-3226
Virtualization: qemu.org | libvirt.org
signature.asc
Description: OpenPGP digital signature