From: "Jose A. Perez de Azpillaga" <azpijr@gmail.com>
To: Pratyush Yadav <pratyush@kernel.org>
Cc: Tony Luck <tony.luck@intel.com>,
Pasha Tatashin <pasha.tatashin@soleen.com>,
linux-mm@kvack.org, Kees Cook <kees@kernel.org>,
Changyuan Lyu <changyuanl@google.com>,
kexec@lists.infradead.org, linux-kernel@vger.kernel.org,
Alexander Graf <graf@amazon.com>,
Andrew Morton <akpm@linux-foundation.org>,
Mike Rapoport <rppt@kernel.org>
Subject: Re: [RFC PATCH 0/2] memblock: keep reserve_mem regions out of KHO bootmem
Date: Wed, 4 Nov 2026 11:50:02 +0100 [thread overview]
Message-ID: <70686061-787c-4c99-ba5b-ff982c8cc2ad@gmail.com> (raw)
In-Reply-To: <32dd1f28-db55-4674-99bc-74d9d3ab25db@gmail.com>
On 10/22/26 10:16 PM, Jose A. Perez de Azpillaga wrote:
> On 10/22/26 3:37 PM, Pratyush Yadav wrote:
>> On Wed, Oct 21 2026, Jose A. Perez de Azpillaga wrote:
>>
>>> On a KHO boot, a reserve_mem= region that can't be revived (new name,
>>> size or alignment) can be allocated from KHO bootmem, which the next
>>> kernel boots out of. With CONFIG_KEXEC_HANDOVER_DEBUG preserving it
>>> fails; without it, the next kernel's memmap ends up on top of it.
>> What's your use-case? Why are you adding new reserve_mem regions after
>> cold boot? I'd rather avoid making purely theoretical fixes.
>
> I don't have one, I found it through the TODO. a different reserve_mem=
> in the cmdline passed to kexec is enough to hit it.
>
> if it isn't meant to work across a live update, would you rather have
> reserve_mem() fail on KHO boot when it can't revive the region?
>
ping, I can send a v2 either way.
--
cheers,
jose a. p-a
WARNING: multiple messages have this Message-ID (diff)
From: "Jose A. Perez de Azpillaga" <azpijr@gmail.com>
To: Pratyush Yadav <pratyush@kernel.org>
Cc: Mike Rapoport <rppt@kernel.org>,
Andrew Morton <akpm@linux-foundation.org>,
Kees Cook <kees@kernel.org>, Alexander Graf <graf@amazon.com>,
Changyuan Lyu <changyuanl@google.com>,
Tony Luck <tony.luck@intel.com>,
"Guilherme G. Piccoli" <gpiccoli@igalia.com>,
linux-mm@kvack.org, linux-kernel@vger.kernel.org,
Pasha Tatashin <pasha.tatashin@soleen.com>,
kexec@lists.infradead.org
Subject: Re: [RFC PATCH 0/2] memblock: keep reserve_mem regions out of KHO bootmem
Date: Wed, 4 Nov 2026 11:50:02 +0100 [thread overview]
Message-ID: <70686061-787c-4c99-ba5b-ff982c8cc2ad@gmail.com> (raw)
In-Reply-To: <32dd1f28-db55-4674-99bc-74d9d3ab25db@gmail.com>
On 10/22/26 10:16 PM, Jose A. Perez de Azpillaga wrote:
> On 10/22/26 3:37 PM, Pratyush Yadav wrote:
>> On Wed, Oct 21 2026, Jose A. Perez de Azpillaga wrote:
>>
>>> On a KHO boot, a reserve_mem= region that can't be revived (new name,
>>> size or alignment) can be allocated from KHO bootmem, which the next
>>> kernel boots out of. With CONFIG_KEXEC_HANDOVER_DEBUG preserving it
>>> fails; without it, the next kernel's memmap ends up on top of it.
>> What's your use-case? Why are you adding new reserve_mem regions after
>> cold boot? I'd rather avoid making purely theoretical fixes.
>
> I don't have one, I found it through the TODO. a different reserve_mem=
> in the cmdline passed to kexec is enough to hit it.
>
> if it isn't meant to work across a live update, would you rather have
> reserve_mem() fail on KHO boot when it can't revive the region?
>
ping, I can send a v2 either way.
--
cheers,
jose a. p-a
next prev parent reply other threads:[~2026-11-04 10:50 UTC|newest]
Thread overview: 18+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-10-21 21:10 [RFC PATCH 0/2] memblock: keep reserve_mem regions out of KHO bootmem Jose A. Perez de Azpillaga
2026-10-21 21:10 ` Jose A. Perez de Azpillaga
2026-10-21 21:10 ` [RFC PATCH 1/2] memblock: factor out the KHO bootmem check from memblock_alloc_hugetlb() Jose A. Perez de Azpillaga
2026-10-21 21:10 ` Jose A. Perez de Azpillaga
2026-10-21 21:20 ` sashiko-bot
2026-10-21 21:10 ` [RFC PATCH 2/2] memblock: don't allocate reserve_mem regions from KHO bootmem Jose A. Perez de Azpillaga
2026-10-21 21:10 ` Jose A. Perez de Azpillaga
2026-10-21 21:20 ` sashiko-bot
2026-10-22 13:37 ` [RFC PATCH 0/2] memblock: keep reserve_mem regions out of " Pratyush Yadav
2026-10-22 13:37 ` Pratyush Yadav
2026-10-22 20:16 ` Jose A. Perez de Azpillaga
2026-10-22 20:16 ` Jose A. Perez de Azpillaga
2026-11-04 10:50 ` Jose A. Perez de Azpillaga [this message]
2026-11-04 10:50 ` Jose A. Perez de Azpillaga
2026-11-04 12:19 ` Pratyush Yadav
2026-11-04 12:19 ` Pratyush Yadav
2026-11-04 12:29 ` Jose A. Perez de Azpillaga
2026-11-04 12:29 ` Jose A. Perez de Azpillaga
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=70686061-787c-4c99-ba5b-ff982c8cc2ad@gmail.com \
--to=azpijr@gmail.com \
--cc=akpm@linux-foundation.org \
--cc=changyuanl@google.com \
--cc=graf@amazon.com \
--cc=kees@kernel.org \
--cc=kexec@lists.infradead.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-mm@kvack.org \
--cc=pasha.tatashin@soleen.com \
--cc=pratyush@kernel.org \
--cc=rppt@kernel.org \
--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 an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.