From: Mike Rapoport <rppt@linux.ibm.com>
To: Lukas Bulwahn <lukas.bulwahn@gmail.com>
Cc: Russell King <linux@armlinux.org.uk>,
linux-arm-kernel@lists.infradead.org,
Thomas Gleixner <tglx@linutronix.de>,
Ingo Molnar <mingo@redhat.com>, Borislav Petkov <bp@alien8.de>,
Dave Hansen <dave.hansen@linux.intel.com>,
x86@kernel.org, Mauro Carvalho Chehab <mchehab@kernel.org>,
linux-media@vger.kernel.org, Peter Chen <peter.chen@kernel.org>,
Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
linux-usb@vger.kernel.org,
Andrew Morton <akpm@linux-foundation.org>,
linux-mm@kvack.org, Masahiro Yamada <masahiroy@kernel.org>,
linux-kbuild@vger.kernel.org, kernel-janitors@vger.kernel.org,
linux-kernel@vger.kernel.org
Subject: Re: [PATCH 5/6] mm: Kconfig: make config SECRETMEM visible with EXPERT
Date: Thu, 8 Sep 2022 14:24:15 +0300 [thread overview]
Message-ID: <YxnQ3+0BfbmUbBnH@linux.ibm.com> (raw)
In-Reply-To: <20220908104337.11940-6-lukas.bulwahn@gmail.com>
On Thu, Sep 08, 2022 at 12:43:36PM +0200, Lukas Bulwahn wrote:
> Commit 6a108a14fa35 ("kconfig: rename CONFIG_EMBEDDED to CONFIG_EXPERT")
> introduces CONFIG_EXPERT to carry the previous intent of CONFIG_EMBEDDED
> and just gives that intent a much better name. That has been clearly a good
> and long overdue renaming, and it is clearly an improvement to the kernel
> build configuration that has shown to help managing the kernel build
> configuration in the last decade.
>
> However, rather than bravely and radically just deleting CONFIG_EMBEDDED,
> this commit gives CONFIG_EMBEDDED a new intended semantics, but keeps it
> open for future contributors to implement that intended semantics:
>
> A new CONFIG_EMBEDDED option is added that automatically selects
> CONFIG_EXPERT when enabled and can be used in the future to isolate
> options that should only be considered for embedded systems (RISC
> architectures, SLOB, etc).
>
> Since then, this CONFIG_EMBEDDED implicitly had two purposes:
>
> - It can make even more options visible beyond what CONFIG_EXPERT makes
> visible. In other words, it may introduce another level of enabling the
> visibility of configuration options: always visible, visible with
> CONFIG_EXPERT and visible with CONFIG_EMBEDDED.
>
> - Set certain default values of some configurations differently,
> following the assumption that configuring a kernel build for an
> embedded system generally starts with a different set of default values
> compared to kernel builds for all other kind of systems.
>
> Considering the second purpose, note that already probably arguing that a
> kernel build for an embedded system would choose some values differently is
> already tricky: the set of embedded systems with Linux kernels is already
> quite diverse. Many embedded system have powerful CPUs and it would not be
> clear that all embedded systems just optimize towards one specific aspect,
> e.g., a smaller kernel image size. So, it is unclear if starting with "one
> set of default configuration" that is induced by CONFIG_EMBEDDED is a good
> offer for developers configuring their kernels.
>
> Also, the differences of needed user-space features in an embedded system
> compared to a non-embedded system are probably difficult or even impossible
> to name in some generic way.
>
> So it is not surprising that in the last decade hardly anyone has
> contributed changes to make something default differently in case of
> CONFIG_EMBEDDED=y.
>
> Currently, in v6.0-rc4, SECRETMEM is the only config switched off if
> CONFIG_EMBEDDED=y.
>
> As long as that is actually the only option that currently is selected or
> deselected, it is better to just make SECRETMEM configurable at build time
> by experts using menuconfig instead.
>
> Make SECRETMEM configurable when EXPERT is set and otherwise default to
> yes. Further, SECRETMEM needs ARCH_HAS_SET_DIRECT_MAP.
>
> This allows us to remove CONFIG_EMBEDDED in the close future.
>
> Signed-off-by: Lukas Bulwahn <lukas.bulwahn@gmail.com>
Acked-by: Mike Rapoport <rppt@linux.ibm.com>
> ---
> mm/Kconfig | 8 +++++++-
> 1 file changed, 7 insertions(+), 1 deletion(-)
>
> diff --git a/mm/Kconfig b/mm/Kconfig
> index ceec438c0741..aa154c20b129 100644
> --- a/mm/Kconfig
> +++ b/mm/Kconfig
> @@ -1068,7 +1068,13 @@ config IO_MAPPING
> bool
>
> config SECRETMEM
> - def_bool ARCH_HAS_SET_DIRECT_MAP && !EMBEDDED
> + default y
> + bool "Enable memfd_secret() system call" if EXPERT
> + depends on ARCH_HAS_SET_DIRECT_MAP
> + help
> + Enable the memfd_secret() system call with the ability to create
> + memory areas visible only in the context of the owning process and
> + not mapped to other processes and other kernel page tables.
>
> config ANON_VMA_NAME
> bool "Anonymous VMA name support"
> --
> 2.17.1
>
--
Sincerely yours,
Mike.
next prev parent reply other threads:[~2022-09-08 11:25 UTC|newest]
Thread overview: 20+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-09-08 10:43 [PATCH 0/6] Remove CONFIG_EMBEDDED Lukas Bulwahn
2022-09-08 10:43 ` [PATCH 1/6] arm: make config ARM_PATCH_PHYS_VIRT visible with EXPERT Lukas Bulwahn
2022-09-09 6:21 ` Masahiro Yamada
2022-09-08 10:43 ` [PATCH 2/6] x86: make config X86_FEATURE_NAMES " Lukas Bulwahn
2022-09-09 6:22 ` Masahiro Yamada
2022-09-08 10:43 ` [PATCH 3/6] media: remove reference to CONFIG_EMBEDDED in MEDIA_SUPPORT_FILTER Lukas Bulwahn
2022-09-08 11:13 ` Mauro Carvalho Chehab
2022-09-08 16:20 ` Mauro Carvalho Chehab
2022-09-09 6:22 ` Masahiro Yamada
2022-09-08 10:43 ` [PATCH 4/6] usb: chipidea: make configs for glue drivers visible with EXPERT Lukas Bulwahn
2022-09-08 11:33 ` Greg Kroah-Hartman
2022-09-09 6:22 ` Masahiro Yamada
2022-09-08 10:43 ` [PATCH 5/6] mm: Kconfig: make config SECRETMEM " Lukas Bulwahn
2022-09-08 11:24 ` Mike Rapoport [this message]
2022-09-09 6:22 ` Masahiro Yamada
2022-09-08 10:43 ` [PATCH 6/6] init/Kconfig: remove confusing config EMBEDDED Lukas Bulwahn
2022-09-09 6:24 ` Masahiro Yamada
2022-09-09 9:23 ` Christophe Leroy
2022-09-09 9:47 ` Lukas Bulwahn
2022-09-08 15:21 ` [PATCH 0/6] Remove CONFIG_EMBEDDED Arnd Bergmann
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=YxnQ3+0BfbmUbBnH@linux.ibm.com \
--to=rppt@linux.ibm.com \
--cc=akpm@linux-foundation.org \
--cc=bp@alien8.de \
--cc=dave.hansen@linux.intel.com \
--cc=gregkh@linuxfoundation.org \
--cc=kernel-janitors@vger.kernel.org \
--cc=linux-arm-kernel@lists.infradead.org \
--cc=linux-kbuild@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-media@vger.kernel.org \
--cc=linux-mm@kvack.org \
--cc=linux-usb@vger.kernel.org \
--cc=linux@armlinux.org.uk \
--cc=lukas.bulwahn@gmail.com \
--cc=masahiroy@kernel.org \
--cc=mchehab@kernel.org \
--cc=mingo@redhat.com \
--cc=peter.chen@kernel.org \
--cc=tglx@linutronix.de \
--cc=x86@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).