linux-kernel - Re: [PATCH v2] iommu/vt-d: avoid unnecessory panic if iommu init fail in tboot system

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: <4cfa1f1827e0ccbfbc94de3beba64a4a141b2248.camel@linux.intel.com>
Date:   Tue, 10 Nov 2020 16:53:33 +0100
From:   Lukasz Hawrylko <lukasz.hawrylko@...ux.intel.com>
To:     Zhenzhong Duan <zhenzhong.duan@...il.com>,
        linux-kernel@...r.kernel.org
Cc:     ning.sun@...el.com, tglx@...utronix.de, mingo@...hat.com,
        bp@...en8.de, x86@...nel.org, dwmw2@...radead.org,
        baolu.lu@...ux.intel.com, joro@...tes.org,
        iommu@...ts.linux-foundation.org, tboot-devel@...ts.sourceforge.net
Subject: Re: [PATCH v2] iommu/vt-d: avoid unnecessory panic if iommu init
 fail in tboot system

Hi Zhenzhong

On Tue, 2020-11-10 at 15:19 +0800, Zhenzhong Duan wrote:
> "intel_iommu=off" command line is used to disable iommu but iommu is force
> enabled in a tboot system for security reason.
> 
> However for better performance on high speed network device, a new option
> "intel_iommu=tboot_noforce" is introduced to disable the force on.
> 
> By default kernel should panic if iommu init fail in tboot for security
> reason, but it's unnecessory if we use "intel_iommu=tboot_noforce,off".
> 
> Fix the code setting force_on and move intel_iommu_tboot_noforce
> from tboot code to intel iommu code.
> 
> Fixes: 7304e8f28bb2 ("iommu/vt-d: Correctly disable Intel IOMMU force on")
> Signed-off-by: Zhenzhong Duan <zhenzhong.duan@...il.com>
> ---
> v2: move ckeck of intel_iommu_tboot_noforce into iommu code per Baolu.

I have check it on my TXT testing environment with latest TBOOT,
everything works as expected.

Thanks,
Lukasz