From: Borislav Petkov <bp@alien8.de>
To: Thomas Gleixner <tglx@linutronix.de>
Cc: LKML <linux-kernel@vger.kernel.org>,
x86@kernel.org, Paul Menzel <pmenzel@molgen.mpg.de>,
Joerg Roedel <joro@8bytes.org>, Kees Cook <keescook@chromium.org>,
Bjorn Helgaas <bhelgaas@google.com>
Subject: Re: [PATCH] x86/mm: Do not warn about PCI BIOS W+X mappings
Date: Mon, 8 Oct 2018 22:01:15 +0200 [thread overview]
Message-ID: <20181008200115.GC5919@zn.tnic> (raw)
In-Reply-To: <alpine.DEB.2.21.1810082151160.2455@nanos.tec.linutronix.de>
On Mon, Oct 08, 2018 at 09:53:48PM +0200, Thomas Gleixner wrote:
> PCI BIOS requires the BIOS area 0x0A0000-0x0FFFFFF to be mapped W+X for
> various legacy reasons. When CONFIG_DEBUG_WX is enabled, this triggers the
> WX warning, but this is misleading because the mapping is required and is
> not a result of an accidental oversight.
>
> Prevent the full warning when PCI BIOS is enabled and the detected WX
> mapping is in the BIOS area. Just emit a pr_warn() which denotes the
> fact. This is partially duplicating the info which the PCI BIOS code emits
> when it maps the area as executable, but that info is not in the context of
> the WX checking output.
>
> Reported-by: Paul Menzel <pmenzel@molgen.mpg.de>
> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
> Cc: Joerg Roedel <joro@8bytes.org>
> Cc: Kees Cook <keescook@chromium.org>
> Cc: Bjorn Helgaas <bhelgaas@google.com>
Tested-by: Borislav Petkov <bp@suse.de>
--
Regards/Gruss,
Boris.
Good mailing practices for 400: avoid top-posting and trim the reply.
next prev parent reply other threads:[~2018-10-08 20:01 UTC|newest]
Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-10-08 19:53 [PATCH] x86/mm: Do not warn about PCI BIOS W+X mappings Thomas Gleixner
2018-10-08 20:01 ` Borislav Petkov [this message]
2018-10-09 0:00 ` Kees Cook
2018-10-10 13:18 ` [tip:x86/mm] " tip-bot for Thomas Gleixner
2018-10-11 23:23 ` [PATCH] " Paul Menzel
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=20181008200115.GC5919@zn.tnic \
--to=bp@alien8.de \
--cc=bhelgaas@google.com \
--cc=joro@8bytes.org \
--cc=keescook@chromium.org \
--cc=linux-kernel@vger.kernel.org \
--cc=pmenzel@molgen.mpg.de \
--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).