From: Andrew Morton <akpm@linux-foundation.org>
To: Taku Izumi <izumi.taku@jp.fujitsu.com>
Cc: linux-kernel@vger.kernel.org, linux-mm@kvack.org,
tony.luck@intel.com, qiuxishi@huawei.com,
kamezawa.hiroyu@jp.fujitsu.com, mel@csn.ul.ie,
dave.hansen@intel.com, matt@codeblueprint.co.uk
Subject: Re: [PATCH v3 2/2] mm: Introduce kernelcore=mirror option
Date: Mon, 28 Dec 2015 14:21:08 -0800 [thread overview]
Message-ID: <20151228142108.fa679ebf9d3a91ad14924977@linux-foundation.org> (raw)
In-Reply-To: <1449631177-14863-1-git-send-email-izumi.taku@jp.fujitsu.com>
On Wed, 9 Dec 2015 12:19:37 +0900 Taku Izumi <izumi.taku@jp.fujitsu.com> wrote:
> This patch extends existing "kernelcore" option and
> introduces kernelcore=mirror option. By specifying
> "mirror" instead of specifying the amount of memory,
> non-mirrored (non-reliable) region will be arranged
> into ZONE_MOVABLE.
>
> v1 -> v2:
> - Refine so that the following case also can be
> handled properly:
>
> Node X: |MMMMMM------MMMMMM--------|
> (legend) M: mirrored -: not mirrrored
>
> In this case, ZONE_NORMAL and ZONE_MOVABLE are
> arranged like bellow:
>
> Node X: |MMMMMM------MMMMMM--------|
> |ooooooxxxxxxooooooxxxxxxxx| ZONE_NORMAL
> |ooooooxxxxxxoooooooo| ZONE_MOVABLE
> (legend) o: present x: absent
>
> v2 -> v3:
> - change the option name from kernelcore=reliable
> into kernelcore=mirror
> - documentation fix so that users can understand
> nn[KMS] and mirror are exclusive
My earlier concern with this approach is the assumption that *all* of
the mirrored memory will be used to kernelcore. The user might want to
use half the machine's mirrored memory for kernelcore and half for
regular memory but cannot do so.
However I think what I'm seeing from the discussion is that in this
case, the user can alter the amount of mirrored memory via EFI to
achieve the same effect.
Is this correct? If so, should we document this somewhere and provide
our users with instructions on how to make the required EFI changes?
Or is this all so totally obvious to them that there is no need?
next prev parent reply other threads:[~2015-12-28 22:21 UTC|newest]
Thread overview: 20+ messages / expand[flat|nested] mbox.gz Atom feed top
2015-12-09 3:18 [PATCH v3 0/2] mm: Introduce kernelcore=mirror option Taku Izumi
2015-12-09 3:19 ` [PATCH v3 1/2] mm: Calculate zone_start_pfn at zone_spanned_pages_in_node() Taku Izumi
2015-12-09 3:19 ` [PATCH v3 2/2] mm: Introduce kernelcore=mirror option Taku Izumi
2015-12-09 3:28 ` Xishi Qiu
2015-12-09 21:59 ` Luck, Tony
2015-12-10 1:14 ` Xishi Qiu
2015-12-10 5:37 ` Izumi, Taku
2015-12-10 6:13 ` Xishi Qiu
2015-12-11 5:53 ` Izumi, Taku
2015-12-11 9:44 ` Xishi Qiu
2015-12-17 1:38 ` Izumi, Taku
2015-12-17 2:47 ` Xishi Qiu
2015-12-17 2:53 ` Kamezawa Hiroyuki
2015-12-17 4:48 ` Xishi Qiu
2015-12-17 5:01 ` Kamezawa Hiroyuki
2015-12-17 18:43 ` Luck, Tony
2015-12-18 2:12 ` Kamezawa Hiroyuki
2015-12-18 6:59 ` Luck, Tony
2015-12-28 22:21 ` Andrew Morton [this message]
2015-12-28 22:32 ` Andrew Morton
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=20151228142108.fa679ebf9d3a91ad14924977@linux-foundation.org \
--to=akpm@linux-foundation.org \
--cc=dave.hansen@intel.com \
--cc=izumi.taku@jp.fujitsu.com \
--cc=kamezawa.hiroyu@jp.fujitsu.com \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-mm@kvack.org \
--cc=matt@codeblueprint.co.uk \
--cc=mel@csn.ul.ie \
--cc=qiuxishi@huawei.com \
--cc=tony.luck@intel.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 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).