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Mon, 28 Sep 2026 06:08:45 -0700 (PDT) Received: from jgg by wakko with local (Exim 4.97) (envelope-from ) id 1xBB63-00000006mlN-3bcU; Mon, 28 Sep 2026 10:08:43 -0300 Date: Mon, 28 Sep 2026 10:08:43 -0300 From: Jason Gunthorpe To: "Tian, Kevin" Cc: "Aneesh Kumar K.V (Arm)" , "linux-coco@lists.linux.dev" , "iommu@lists.linux.dev" , "linux-kernel@vger.kernel.org" , "kvm@vger.kernel.org" , Alexey Kardashevskiy , Bjorn Helgaas , Joerg Roedel , Jonathan Cameron , Nicolin Chen , Samuel Ortiz , Steven Price , Suzuki K Poulose , Will Deacon , Xu Yilun , Shameer Kolothum , Paolo Bonzini Subject: Re: [RFC PATCH v6 00/11] iommufd: Infrastructure for vIOMMU creation for confidential guests and guest TSM requests Message-ID: <20260928130843.GH163130@ziepe.ca> References: <20260917140159.1163281-1-aneesh.kumar@kernel.org> <20260924192054.GA16465@ziepe.ca> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: On Mon, Sep 28, 2026 at 03:35:29AM +0000, Tian, Kevin wrote: > Looks there are some resource shared between the untrust and > trust invalidation paths, as iommu->qi->q_lock is also acquired > in the trust path. I still need to understand the motivation behind, > but this can be resolved properly by exporting a helper to the > TSM driver even if it's truly required. That seems a bit suspicious from a security POV.. The secure side shouldn't be sharing anything like this with the insecure side, that's just inviting invalidation integrity attacks??? Jason