From: Alexandre Ghiti <alexghiti@rivosinc.com>
To: "Rafael J . Wysocki" <rafael.j.wysocki@intel.com>,
"Pavel Machek" <pavel@ucw.cz>,
linux-pm@vger.kernel.org,
"Paul Walmsley" <paul.walmsley@sifive.com>,
"Palmer Dabbelt" <palmer@dabbelt.com>,
"Albert Ou" <aou@eecs.berkeley.edu>,
"Rob Herring" <robh+dt@kernel.org>,
"Frank Rowand" <frowand.list@gmail.com>,
"Atish Patra" <atishp@atishpatra.org>,
"Anup Patel" <anup@brainfault.org>,
"Björn Töpel" <bjorn@rivosinc.com>,
"Conor Dooley" <conor.dooley@microchip.com>,
linux-riscv@lists.infradead.org, linux-kernel@vger.kernel.org,
devicetree@vger.kernel.org
Cc: Alexandre Ghiti <alexghiti@rivosinc.com>
Subject: [RFC PATCH 0/1] fdt: Mark "/reserved-memory" nodes as nosave if !reusable
Date: Tue, 30 May 2023 10:04:24 +0200 [thread overview]
Message-ID: <20230530080425.18612-1-alexghiti@rivosinc.com> (raw)
In the RISC-V kernel, the firmware does not mark the region it uses as
"no-map" so that the kernel can avoid having holes in the linear mapping
and then use larger pages.
But with the recent support of hibernation on RISC-V, we noticed that
the hibernation process was trying to access those firmware regions
which are protected from *all* accesses (using PMP). So the hibernation
process fails.
We still don't have any "specification" regarding the naming of those
firmware regions, so we can't currently target those specific regions
(they are described as subnodes of "/reserved-memory").
I think we should actually mark all those "/reserved-memory" regions as
"nosave" since they should not be used by the kernel (see the
documentation pointed in the patch), hence the RFC since I may be
missing something here (legacy, other usage...etc).
Please let me know what you think!
Alexandre Ghiti (1):
fdt: Mark "/reserved-memory" nodes as nosave if !reusable
arch/riscv/kernel/setup.c | 2 +
drivers/of/fdt.c | 77 +++++++++++++++++++++++++++++++++++++++
include/linux/of_fdt.h | 1 +
3 files changed, 80 insertions(+)
--
2.39.2
_______________________________________________
linux-riscv mailing list
linux-riscv@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-riscv
next reply other threads:[~2023-05-30 8:04 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-05-30 8:04 Alexandre Ghiti [this message]
2023-05-30 8:04 ` [RFC PATCH 1/1] fdt: Mark "/reserved-memory" nodes as nosave if !reusable Alexandre Ghiti
2023-06-09 14:54 ` Rob Herring
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=20230530080425.18612-1-alexghiti@rivosinc.com \
--to=alexghiti@rivosinc.com \
--cc=anup@brainfault.org \
--cc=aou@eecs.berkeley.edu \
--cc=atishp@atishpatra.org \
--cc=bjorn@rivosinc.com \
--cc=conor.dooley@microchip.com \
--cc=devicetree@vger.kernel.org \
--cc=frowand.list@gmail.com \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-pm@vger.kernel.org \
--cc=linux-riscv@lists.infradead.org \
--cc=palmer@dabbelt.com \
--cc=paul.walmsley@sifive.com \
--cc=pavel@ucw.cz \
--cc=rafael.j.wysocki@intel.com \
--cc=robh+dt@kernel.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).