From: Oscar Salvador <osalvador@suse.de>
To: Naoya Horiguchi <naoya.horiguchi@linux.dev>
Cc: linux-mm@kvack.org, Andrew Morton <akpm@linux-foundation.org>,
Miaohe Lin <linmiaohe@huawei.com>,
David Hildenbrand <david@redhat.com>,
Mike Kravetz <mike.kravetz@oracle.com>,
Yang Shi <shy828301@gmail.com>,
Muchun Song <songmuchun@bytedance.com>,
Jane Chu <jane.chu@oracle.com>,
Naoya Horiguchi <naoya.horiguchi@nec.com>,
linux-kernel@vger.kernel.org
Subject: Re: [PATCH v6 4/4] mm/hwpoison: introduce per-memory_block hwpoison counter
Date: Thu, 13 Oct 2022 10:33:45 +0200 [thread overview]
Message-ID: <Y0fNaYGvnMdwHkg1@localhost.localdomain> (raw)
In-Reply-To: <20221007010706.2916472-5-naoya.horiguchi@linux.dev>
On Fri, Oct 07, 2022 at 10:07:06AM +0900, Naoya Horiguchi wrote:
> From: Naoya Horiguchi <naoya.horiguchi@nec.com>
>
> Currently PageHWPoison flag does not behave well when experiencing memory
> hotremove/hotplug. Any data field in struct page is unreliable when the
> associated memory is offlined, and the current mechanism can't tell whether
> a memory block is onlined because a new memory devices is installed or
> because previous failed offline operations are undone. Especially if
> there's a hwpoisoned memory, it's unclear what the best option is.
>
> So introduce a new mechanism to make struct memory_block remember that
> a memory block has hwpoisoned memory inside it. And make any online event
> fail if the onlining memory block contains hwpoison. struct memory_block
> is freed and reallocated over ACPI-based hotremove/hotplug, but not over
> sysfs-based hotremove/hotplug. So the new counter can distinguish these
> cases.
>
> Signed-off-by: Naoya Horiguchi <naoya.horiguchi@nec.com>
> Reported-by: kernel test robot <lkp@intel.com>
I glanzed over it and looks good overall.
Have a small question though:
> @@ -864,6 +878,7 @@ void remove_memory_block_devices(unsigned long start, unsigned long size)
> mem = find_memory_block_by_id(block_id);
> if (WARN_ON_ONCE(!mem))
> continue;
> + num_poisoned_pages_sub(-1UL, memblk_nr_poison(mem));
Why does num_poisoned_pages_sub() have to make this distinction (!-1 == -1)
for the hot-remove stage?
--
Oscar Salvador
SUSE Labs
next prev parent reply other threads:[~2022-10-13 8:33 UTC|newest]
Thread overview: 17+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-10-07 1:07 [PATCH v6 0/4] mm, hwpoison: improve handling workload related to hugetlb and memory_hotplug Naoya Horiguchi
2022-10-07 1:07 ` [PATCH v6 1/4] mm,hwpoison,hugetlb,memory_hotplug: hotremove memory section with hwpoisoned hugepage Naoya Horiguchi
2022-10-13 14:17 ` Oscar Salvador
2022-10-15 1:58 ` Miaohe Lin
2022-10-17 7:24 ` HORIGUCHI NAOYA(堀口 直也)
2022-10-17 13:29 ` Miaohe Lin
2022-10-07 1:07 ` [PATCH v6 2/4] mm/hwpoison: move definitions of num_poisoned_pages_* to memory-failure.c Naoya Horiguchi
2022-10-13 14:31 ` Oscar Salvador
2022-10-14 6:38 ` Naoya Horiguchi
2022-10-07 1:07 ` [PATCH v6 3/4] mm/hwpoison: pass pfn to num_poisoned_pages_*() Naoya Horiguchi
2022-10-07 1:07 ` [PATCH v6 4/4] mm/hwpoison: introduce per-memory_block hwpoison counter Naoya Horiguchi
2022-10-07 4:34 ` HORIGUCHI NAOYA(堀口 直也)
2022-10-13 8:33 ` Oscar Salvador [this message]
2022-10-13 10:09 ` Naoya Horiguchi
2022-10-15 2:28 ` Miaohe Lin
2022-10-17 11:43 ` HORIGUCHI NAOYA(堀口 直也)
2022-10-17 13:31 ` Miaohe Lin
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=Y0fNaYGvnMdwHkg1@localhost.localdomain \
--to=osalvador@suse.de \
--cc=akpm@linux-foundation.org \
--cc=david@redhat.com \
--cc=jane.chu@oracle.com \
--cc=linmiaohe@huawei.com \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-mm@kvack.org \
--cc=mike.kravetz@oracle.com \
--cc=naoya.horiguchi@linux.dev \
--cc=naoya.horiguchi@nec.com \
--cc=shy828301@gmail.com \
--cc=songmuchun@bytedance.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).