From: Sasha Levin <sasha.levin@oracle.com>
To: Mel Gorman <mgorman@suse.de>
Cc: Linux Kernel <linux-kernel@vger.kernel.org>,
Linux-MM <linux-mm@kvack.org>,
Aneesh Kumar <aneesh.kumar@linux.vnet.ibm.com>,
Hugh Dickins <hughd@google.com>, Dave Jones <davej@redhat.com>,
Rik van Riel <riel@redhat.com>, Ingo Molnar <mingo@redhat.com>,
Kirill Shutemov <kirill.shutemov@linux.intel.com>,
Linus Torvalds <torvalds@linux-foundation.org>
Subject: Re: [RFC PATCH 0/7] Replace _PAGE_NUMA with PAGE_NONE protections
Date: Tue, 18 Nov 2014 11:33:57 -0500 [thread overview]
Message-ID: <546B74F5.10004@oracle.com> (raw)
In-Reply-To: <20141118154246.GB2725@suse.de>
On 11/18/2014 10:42 AM, Mel Gorman wrote:
> 1. I'm assuming this is a KVM setup but can you confirm?
Yes.
> 2. Are you using numa=fake=N?
Yes. numa=fake=24, which is probably way more nodes on any physical machine
than the new code was tested on?
> 3. If you are using fake NUMA, what happens if you boot without it as
> that should make the patches a no-op?
Nope, still seeing it without fake numa.
> 4. Similarly, does the kernel boot properly without without patches?
Yes, the kernel works fine without the patches both with and without fake
numa.
> 5. Are any other patches applied because the line numbers are not lining
> up exactly?
I have quite a few more patches on top of next, but they're debug patches
that add VM_BUG_ONs in quite a few places.
One thing that was odd is that your patches had merge conflicts when applied
on -next in mm/huge-memory.c, so maybe that's where line number differences
are coming from.
> 6. As my own KVM setup appears broken, can you tell me if the host
> kernel has changed recently? If so, does using an older host kernel
> make a difference?
Nope, I've been using the same host kernel (Ubuntu's 3.16.0-24-generic #32)
for a while now.
> At the moment I'm scratching my head trying to figure out how the
> patches could break 9p like this as I don't believe KVM is doing any
> tricks with the same bits that could result in loss.
This issue reproduces rather easily, I'd be happy to try out debug patches
rather than having you guess at what might have gone wrong.
Thanks,
Sasha
next prev parent reply other threads:[~2014-11-18 16:34 UTC|newest]
Thread overview: 20+ messages / expand[flat|nested] mbox.gz Atom feed top
2014-11-14 13:32 [RFC PATCH 0/7] Replace _PAGE_NUMA with PAGE_NONE protections Mel Gorman
2014-11-14 13:33 ` [PATCH 1/7] mm: Add p[te|md] protnone helpers for use by NUMA balancing Mel Gorman
2014-11-14 13:33 ` [PATCH 2/7] mm: Convert p[te|md]_numa users to p[te|md]_protnone_numa Mel Gorman
2014-11-14 13:33 ` [PATCH 3/7] mm: Convert p[te|md]_mknonnuma and remaining page table manipulations Mel Gorman
2014-11-14 13:33 ` [PATCH 4/7] mm: Remove remaining references to NUMA hinting bits and helpers Mel Gorman
2014-11-14 13:33 ` [PATCH 5/7] mm: numa: Do not trap faults on the huge zero page Mel Gorman
2014-11-14 13:33 ` [PATCH 6/7] x86: mm: Restore original pte_special check Mel Gorman
2014-11-14 13:33 ` [PATCH 7/7] mm: numa: Add paranoid check around pte_protnone_numa Mel Gorman
2014-11-15 1:41 ` [RFC PATCH 0/7] Replace _PAGE_NUMA with PAGE_NONE protections Linus Torvalds
2014-11-15 3:29 ` Sasha Levin
2014-11-18 15:42 ` Mel Gorman
2014-11-18 16:33 ` Sasha Levin [this message]
2014-11-18 16:56 ` Aneesh Kumar K.V
2014-11-18 17:14 ` Mel Gorman
2014-11-18 17:18 ` Sasha Levin
2014-11-19 13:14 ` Mel Gorman
2014-11-17 8:26 ` Aneesh Kumar K.V
2014-11-18 16:01 ` Mel Gorman
2014-11-18 16:33 ` Aneesh Kumar K.V
2014-11-18 17:08 ` Mel Gorman
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=546B74F5.10004@oracle.com \
--to=sasha.levin@oracle.com \
--cc=aneesh.kumar@linux.vnet.ibm.com \
--cc=davej@redhat.com \
--cc=hughd@google.com \
--cc=kirill.shutemov@linux.intel.com \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-mm@kvack.org \
--cc=mgorman@suse.de \
--cc=mingo@redhat.com \
--cc=riel@redhat.com \
--cc=torvalds@linux-foundation.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).