linux-kernel - Re: [RFC v6][PATCH 4/4] intel_txt: force IOMMU on for Intel(R) TXT launch

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20090702213013.GC1419@ucw.cz>
Date:	Thu, 2 Jul 2009 23:30:23 +0200
From:	Pavel Machek <pavel@....cz>
To:	Joseph Cihula <joseph.cihula@...el.com>
Cc:	linux-kernel@...r.kernel.org, mingo@...e.hu, arjan@...ux.intel.com,
	hpa@...or.com, andi@...stfloor.org, chrisw@...s-sol.org,
	jmorris@...ei.org, jbeulich@...ell.com, peterm@...hat.com,
	gang.wei@...el.com, shane.wang@...el.com
Subject: Re: [RFC v6][PATCH 4/4] intel_txt: force IOMMU on for Intel(R) TXT
	launch


On Tue 2009-06-30 19:31:10, Joseph Cihula wrote:
> The tboot module will DMA protect all of memory in order to ensure the that
> kernel will be able to initialize without compromise (from DMA).  Consequently,
> the kernel must enable Intel(R) Virtualization Technology for Directed I/O
> (VT-d or Intel IOMMU) in order to replace this broad protection with the
> appropriate page-granular protection.  Otherwise DMA devices will be unable
> to read or write from memory and the kernel will eventually panic.
> 
> Because runtime IOMMU support is configurable by command line options, this
> patch will force it to be enabled regardless of the options specified, and will
> log a message if it was required to force it on.
> 
> 
>  dmar.c        |    7 +++++++
>  intel-iommu.c |   17 +++++++++++++++--
>  2 files changed, 22 insertions(+), 2 deletions(-)
> 
> Signed-off-by: Joseph Cihula <joseph.cihula@...el.com>
> Signed-off-by: Shane Wang <shane.wang@...el.com>

NAK. Breaks user expectations, misses  docs updates. 

-- 
(english) http://www.livejournal.com/~pavelmachek
(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/