From: Michael Ellerman <patch-notifications@ellerman.id.au>
To: Nathan Fontenot <nfont@linux.vnet.ibm.com>,
linuxppc-dev@lists.ozlabs.org
Cc: ldufour@linux.vnet.ibm.com
Subject: Re: powerpc/pseries: Perform full re-add of CPU for topology update post-migration
Date: Sat, 9 Feb 2019 00:02:48 +1100 (AEDT) [thread overview]
Message-ID: <43wwMb6xxXz9sPZ@ozlabs.org> (raw)
In-Reply-To: <154083861636.18916.18172276232185726281.stgit@ltcalpine2-lp14.aus.stglabs.ibm.com>
On Mon, 2018-10-29 at 18:43:36 UTC, Nathan Fontenot wrote:
> On pseries systems, performing a partition migration can result in
> altering the nodes a CPU is assigned to on the destination system. For
> exampl, pre-migration on the source system CPUs are in node 1 and 3,
> post-migration on the destination system CPUs are in nodes 2 and 3.
>
> Handling the node change for a CPU can cause corruption in the slab
> cache if we hit a timing where a CPUs node is changed while cache_reap()
> is invoked. The corruption occurs because the slab cache code appears
> to rely on the CPU and slab cache pages being on the same node.
>
> The current dynamic updating of a CPUs node done in arch/powerpc/mm/numa.c
> does not prevent us from hitting this scenario.
>
> Changing the device tree property update notification handler that
> recognizes an affinity change for a CPU to do a full DLPAR remove and
> add of the CPU instead of dynamically changing its node resolves this
> issue.
>
> Signed-off-by: Nathan Fontenot <nfont@linux.vnet.ibm.com>
> Signed-off-by: Michael W. Bringmann <mwb@linux.vnet.ibm.com>
> Tested-by: Michael W. Bringmann <mwb@linux.vnet.ibm.com>
Applied to powerpc next, thanks.
https://git.kernel.org/powerpc/c/81b61324922c67f73813d8a9c175f3c1
cheers
prev parent reply other threads:[~2019-02-08 14:33 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-10-29 18:43 [PATCH] powerpc/pseries: Perform full re-add of CPU for topology update post-migration Nathan Fontenot
2019-01-28 15:41 ` Michael Bringmann
2019-01-29 9:37 ` Michael Ellerman
2019-01-29 16:12 ` Michael Bringmann
2019-01-30 12:28 ` Michael Ellerman
2019-02-08 13:02 ` Michael Ellerman [this message]
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=43wwMb6xxXz9sPZ@ozlabs.org \
--to=patch-notifications@ellerman.id.au \
--cc=ldufour@linux.vnet.ibm.com \
--cc=linuxppc-dev@lists.ozlabs.org \
--cc=nfont@linux.vnet.ibm.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).