From: Bharata B Rao <bharata@linux.ibm.com>
To: Reza Arbab <arbab@linux.ibm.com>
Cc: sraithal@linux.vnet.ibm.com, linuxppc-dev@lists.ozlabs.org,
aneesh.kumar@linux.vnet.ibm.com, npiggin@gmail.com
Subject: Re: [PATCH v3 2/2] powerpc/mm/radix: Free PUD table when freeing pagetable
Date: Wed, 31 Jul 2019 11:49:20 +0530 [thread overview]
Message-ID: <20190731061920.GA18807@in.ibm.com> (raw)
In-Reply-To: <20190730193716.dxx25tkov7qz2zhu@arbab-laptop.localdomain>
On Tue, Jul 30, 2019 at 02:37:16PM -0500, Reza Arbab wrote:
> On Fri, Jul 26, 2019 at 10:34:40AM +0530, Bharata B Rao wrote:
> > remove_pagetable() isn't freeing PUD table. This causes memory
> > leak during memory unplug. Fix this.
>
> On x86, this is intentional. See
>
> af2cf278ef4f ("x86/mm/hotplug: Don't remove PGD entries in remove_pagetable()")
> 98fe3633c5a4 ("x86/mm/hotplug: Fix BUG_ON() after hot-remove by not freeing PUD")
>
> Does their reasoning apply to powerpc as well?
x86 seems to maintain some global pgd list that needs to sync'ed up
when PGD entry is freed. Since powerpc doesn't have that equivalent
I don't see that reasoning applying here. However if there is more
to it than just this, then I am not sure.
Regards,
Bharata.
prev parent reply other threads:[~2019-07-31 6:21 UTC|newest]
Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-07-26 5:04 [PATCH v3 0/2] Memory unplug fixes for radix guests Bharata B Rao
2019-07-26 5:04 ` [PATCH v3 1/2] powerpc/mm/radix: Fix PTE/PMD fragment count for early page table mappings Bharata B Rao
2019-07-26 5:04 ` [PATCH v3 2/2] powerpc/mm/radix: Free PUD table when freeing pagetable Bharata B Rao
2019-07-30 19:37 ` Reza Arbab
2019-07-31 6:19 ` Bharata B Rao [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=20190731061920.GA18807@in.ibm.com \
--to=bharata@linux.ibm.com \
--cc=aneesh.kumar@linux.vnet.ibm.com \
--cc=arbab@linux.ibm.com \
--cc=linuxppc-dev@lists.ozlabs.org \
--cc=npiggin@gmail.com \
--cc=sraithal@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).