All of lore.kernel.org
 help / color / mirror / Atom feed
From: David Laight <David.Laight@ACULAB.COM>
To: 'Balbir Singh' <bsingharora@gmail.com>,
	"linuxppc-dev@lists.ozlabs.org" <linuxppc-dev@lists.ozlabs.org>,
	"mpe@ellerman.id.au" <mpe@ellerman.id.au>
Cc: "naveen.n.rao@linux.vnet.ibm.com"
	<naveen.n.rao@linux.vnet.ibm.com>,
	"paulus@samba.org" <paulus@samba.org>
Subject: RE: [PATCH v5 2/7] powerpc/vmlinux.lds: Align __init_begin to 16M
Date: Thu, 29 Jun 2017 11:29:56 +0000	[thread overview]
Message-ID: <063D6719AE5E284EB5DD2968C1650D6DD002D97F@AcuExch.aculab.com> (raw)
In-Reply-To: <20170628170411.28864-3-bsingharora@gmail.com>

From: Balbir Singh
> Sent: 28 June 2017 18:04
> For CONFIG_STRICT_KERNEL_RWX align __init_begin to 16M.
> We use 16M since its the larger of 2M on radix and 16M
> on hash for our linear mapping. The plan is to have
> .text, .rodata and everything upto __init_begin marked
> as RX. Note we still have executable read only data.
> We could further align rodata to another 16M boundary.
> I've used keeping text plus rodata as read-only-executable
> as a trade-off to doing read-only-executable for text and
> read-only for rodata.
...

Doesn't this go against 'address space randomisation'?
(Yes I realise a PIC kernel is probably non-trivial to compile
and load.)

	David

  reply	other threads:[~2017-06-29 11:30 UTC|newest]

Thread overview: 10+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2017-06-28 17:04 [PATCH v5 0/7] Provide STRICT_KERNEL_RWX for powerpc Balbir Singh
2017-06-28 17:04 ` [PATCH v5 1/7] powerpc/lib/code-patching: Use alternate map for patch_instruction() Balbir Singh
2017-06-28 17:04 ` [PATCH v5 2/7] powerpc/vmlinux.lds: Align __init_begin to 16M Balbir Singh
2017-06-29 11:29   ` David Laight [this message]
2017-06-29 11:36     ` Balbir Singh
2017-06-28 17:04 ` [PATCH v5 3/7] powerpc/platform/pseries/lpar: Fix updatepp and updateboltedpp Balbir Singh
2017-06-28 17:04 ` [PATCH v5 4/7] powerpc/mm/hash: Implement mark_rodata_ro() for hash Balbir Singh
2017-06-28 17:04 ` [PATCH v5 5/7] powerpc/mm/radix: Implement mark_rodata_ro() for radix Balbir Singh
2017-06-28 17:04 ` [PATCH v5 6/7] mm/radix: Fix permissions correctly for interrupt_vectors Balbir Singh
2017-06-28 17:04 ` [PATCH v5 7/7] powerpc/Kconfig: Enable STRICT_KERNEL_RWX Balbir Singh

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=063D6719AE5E284EB5DD2968C1650D6DD002D97F@AcuExch.aculab.com \
    --to=david.laight@aculab.com \
    --cc=bsingharora@gmail.com \
    --cc=linuxppc-dev@lists.ozlabs.org \
    --cc=mpe@ellerman.id.au \
    --cc=naveen.n.rao@linux.vnet.ibm.com \
    --cc=paulus@samba.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 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.