linux-arch.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com>
To: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: linux-kernel@vger.kernel.org, linux-arch@vger.kernel.org,
	"H. Peter Anvin" <hpa@zytor.com>, Arnd Bergmann <arnd@arndb.de>,
	Heiko Carstens <heiko.carstens@de.ibm.com>,
	Kees Cook <keescook@chromium.org>,
	Will Deacon <will.deacon@arm.com>,
	Michael Ellerman <mpe@ellerman.id.au>,
	Thomas Garnier <thgarnie@google.com>,
	Thomas Gleixner <tglx@linutronix.de>,
	"Serge E. Hallyn" <serge@hallyn.com>,
	Bjorn Helgaas <bhelgaas@google.com>,
	Benjamin Herrenschmidt <benh@kernel.crashing.org>,
	Paul Mackerras <paulus@samba.org>,
	Catalin Marinas <catalin.marinas@arm.com>,
	Petr Mladek <pmladek@suse.com>, Ingo Molnar <mingo@redhat.com>,
	James Morris <james.l.morris@oracle.com>,
	Andrew Morton <akpm@linux-foundation.org>,
	Nicolas Pitre <nico@linaro.org>, Steven Rostedt <rosted>
Subject: Re: [PATCH 0/5] add support for relative references in special sections
Date: Fri, 18 Aug 2017 14:56:55 +0900	[thread overview]
Message-ID: <20170818055655.GA495@jagdpanzerIV.localdomain> (raw)
In-Reply-To: <20170814105231.14608-1-ard.biesheuvel@linaro.org>

On (08/14/17 11:52), Ard Biesheuvel wrote:
> This adds support for emitting special sections such as initcall arrays,
> PCI fixups and tracepoints as relative references rather than absolute
> references. This reduces the size by 50% on 64-bit architectures, but
> more importantly, it removes the need for carrying relocation metadata
> for these sections in relocatables kernels (e.g., for KASLR) that need
> to fix up these absolute references at boot time. On arm64, this reduces
> the vmlinux footprint of such a reference by 8x (8 byte absolute reference
> + 24 byte RELA entry vs 4 byte relative reference)
[..]

a side note,
checkpatch complaints quite a lot.

	-ss

WARNING: multiple messages have this Message-ID (diff)
From: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com>
To: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: linux-kernel@vger.kernel.org, linux-arch@vger.kernel.org,
	"H. Peter Anvin" <hpa@zytor.com>, Arnd Bergmann <arnd@arndb.de>,
	Heiko Carstens <heiko.carstens@de.ibm.com>,
	Kees Cook <keescook@chromium.org>,
	Will Deacon <will.deacon@arm.com>,
	Michael Ellerman <mpe@ellerman.id.au>,
	Thomas Garnier <thgarnie@google.com>,
	Thomas Gleixner <tglx@linutronix.de>,
	"Serge E. Hallyn" <serge@hallyn.com>,
	Bjorn Helgaas <bhelgaas@google.com>,
	Benjamin Herrenschmidt <benh@kernel.crashing.org>,
	Paul Mackerras <paulus@samba.org>,
	Catalin Marinas <catalin.marinas@arm.com>,
	Petr Mladek <pmladek@suse.com>, Ingo Molnar <mingo@redhat.com>,
	James Morris <james.l.morris@oracle.com>,
	Andrew Morton <akpm@linux-foundation.org>,
	Nicolas Pitre <nico@linaro.org>,
	Steven Rostedt <rostedt@goodmis.org>,
	Martin Schwidefsky <schwidefsky@de.ibm.com>,
	Sergey Senozhatsky <sergey.senozhatsky@gmail.com>,
	Jessica Yu <jeyu@kernel.org>
Subject: Re: [PATCH 0/5] add support for relative references in special sections
Date: Fri, 18 Aug 2017 14:56:55 +0900	[thread overview]
Message-ID: <20170818055655.GA495@jagdpanzerIV.localdomain> (raw)
Message-ID: <20170818055655.Y3OYjyeSugMvh_bBskBzoR6HSaBF_N4CWBDnGincB24@z> (raw)
In-Reply-To: <20170814105231.14608-1-ard.biesheuvel@linaro.org>

On (08/14/17 11:52), Ard Biesheuvel wrote:
> This adds support for emitting special sections such as initcall arrays,
> PCI fixups and tracepoints as relative references rather than absolute
> references. This reduces the size by 50% on 64-bit architectures, but
> more importantly, it removes the need for carrying relocation metadata
> for these sections in relocatables kernels (e.g., for KASLR) that need
> to fix up these absolute references at boot time. On arm64, this reduces
> the vmlinux footprint of such a reference by 8x (8 byte absolute reference
> + 24 byte RELA entry vs 4 byte relative reference)
[..]

a side note,
checkpatch complaints quite a lot.

	-ss

  parent reply	other threads:[~2017-08-18  5:56 UTC|newest]

Thread overview: 34+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2017-08-14 10:52 [PATCH 0/5] add support for relative references in special sections Ard Biesheuvel
2017-08-14 10:52 ` Ard Biesheuvel
2017-08-14 10:52 ` [PATCH 1/5] arch: enable relative relocations for arm64, power, x86, s390 and x86 Ard Biesheuvel
2017-08-14 10:52   ` Ard Biesheuvel
2017-08-14 10:52 ` [PATCH 2/5] module: use relative references for __ksymtab entries Ard Biesheuvel
2017-08-14 10:52   ` Ard Biesheuvel
2017-08-14 10:52 ` [PATCH 3/5] init: allow initcall tables to be emitted using relative references Ard Biesheuvel
2017-08-14 10:52   ` Ard Biesheuvel
2017-08-14 10:52 ` [PATCH 4/5] drivers: pci: add support for relative addressing in quirk tables Ard Biesheuvel
2017-08-14 10:52   ` Ard Biesheuvel
2017-08-14 10:52 ` [PATCH 5/5] kernel: tracepoints: add support for relative references Ard Biesheuvel
2017-08-14 10:52   ` Ard Biesheuvel
2017-08-14 15:23   ` Steven Rostedt
2017-08-14 15:23     ` Steven Rostedt
2017-08-14 15:29     ` Ard Biesheuvel
2017-08-14 15:29       ` Ard Biesheuvel
2017-08-18  8:26   ` Ingo Molnar
2017-08-18  8:26     ` Ingo Molnar
2017-08-18  8:36     ` Ard Biesheuvel
2017-08-18  8:36       ` Ard Biesheuvel
2017-08-18  9:24       ` Ard Biesheuvel
2017-08-18  9:24         ` Ard Biesheuvel
2017-08-18 17:58         ` Ingo Molnar
2017-08-18 17:58           ` Ingo Molnar
2017-08-18 18:17           ` Ard Biesheuvel
2017-08-18 18:17             ` Ard Biesheuvel
2017-08-18  5:56 ` Sergey Senozhatsky [this message]
2017-08-18  5:56   ` [PATCH 0/5] add support for relative references in special sections Sergey Senozhatsky
2017-08-18  6:12   ` Ard Biesheuvel
2017-08-18  6:12     ` Ard Biesheuvel
2017-08-18  6:29     ` Sergey Senozhatsky
2017-08-18  6:29       ` Sergey Senozhatsky
2017-08-18  6:33       ` Ard Biesheuvel
2017-08-18  6:33         ` Ard Biesheuvel

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=20170818055655.GA495@jagdpanzerIV.localdomain \
    --to=sergey.senozhatsky.work@gmail.com \
    --cc=akpm@linux-foundation.org \
    --cc=ard.biesheuvel@linaro.org \
    --cc=arnd@arndb.de \
    --cc=benh@kernel.crashing.org \
    --cc=bhelgaas@google.com \
    --cc=catalin.marinas@arm.com \
    --cc=heiko.carstens@de.ibm.com \
    --cc=hpa@zytor.com \
    --cc=james.l.morris@oracle.com \
    --cc=keescook@chromium.org \
    --cc=linux-arch@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=mingo@redhat.com \
    --cc=mpe@ellerman.id.au \
    --cc=nico@linaro.org \
    --cc=paulus@samba.org \
    --cc=pmladek@suse.com \
    --cc=serge@hallyn.com \
    --cc=tglx@linutronix.de \
    --cc=thgarnie@google.com \
    --cc=will.deacon@arm.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).