From: Nathan_Lynch@mentor•com (Nathan Lynch)
To: linux-arm-kernel@lists•infradead.org
Subject: [PATCH 1/3] arm64: vdso: put vdso datapage in a separate vma
Date: Wed, 9 Jul 2014 14:44:33 -0500 [thread overview]
Message-ID: <53BD9BA1.4070103@mentor.com> (raw)
In-Reply-To: <1404930133-30324-2-git-send-email-will.deacon@arm.com>
Hi Will, one question (and maybe it's more of a question for Andy than
for you).
On 07/09/2014 01:22 PM, Will Deacon wrote:
> - ret = install_special_mapping(mm, vdso_base, vdso_mapping_len,
> + ret = install_special_mapping(mm, vdso_base, vdso_text_len,
> VM_READ|VM_EXEC|
> VM_MAYREAD|VM_MAYWRITE|VM_MAYEXEC,
> vdso_pagelist);
> - if (ret) {
> - mm->context.vdso = NULL;
> + if (ret)
> + goto up_fail;
> +
> + vdso_base += vdso_text_len;
> + ret = install_special_mapping(mm, vdso_base, PAGE_SIZE,
> + VM_READ|VM_MAYREAD,
> + vdso_pagelist + vdso_pages);
I note this code sets VM_MAYREAD for the data page, while x86's vvar
mapping sets only VM_READ. (Personally I am not totally clear on the
meaning of VM_MAYREAD, but it looks like it would have implications for
use of mprotect on the mapping.) Should one arch or the other adjust
its flags?
next prev parent reply other threads:[~2014-07-09 19:44 UTC|newest]
Thread overview: 7+ messages / expand[flat|nested] mbox.gz Atom feed top
2014-07-09 18:22 [PATCH 0/3] Bunch of vdso cleanups following feedback from x86 Will Deacon
2014-07-09 18:22 ` [PATCH 1/3] arm64: vdso: put vdso datapage in a separate vma Will Deacon
2014-07-09 19:44 ` Nathan Lynch [this message]
2014-07-09 19:48 ` Andy Lutomirski
2014-07-09 18:22 ` [PATCH 2/3] arm64: vdso: move to _install_special_mapping and remove arch_vma_name Will Deacon
2014-07-09 18:22 ` [PATCH 3/3] arm64: vdso: move data page before code pages Will Deacon
2014-07-24 18:20 ` [PATCH 0/3] Bunch of vdso cleanups following feedback from x86 Christopher Covington
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=53BD9BA1.4070103@mentor.com \
--to=nathan_lynch@mentor$(echo .)com \
--cc=linux-arm-kernel@lists$(echo .)infradead.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
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