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[54.240.197.234]) by smtp.gmail.com with ESMTPSA id 5b1f17b1804b1-4a1cca43012sm17041055e9.3.2026.10.16.02.46.10 (version=TLS1_2 cipher=ECDHE-ECDSA-AES128-GCM-SHA256 bits=128/128); Fri, 16 Oct 2026 02:46:12 -0700 (PDT) From: Fred Griffoul To: Paolo Bonzini , Sean Christopherson , Marc Zyngier , Oliver Upton , Catalin Marinas , Andrew Morton , David Hildenbrand , Alexander Viro , Christian Brauner , Jan Kara , Jason Gunthorpe , Kevin Tian , Joerg Roedel , Will Deacon , Robin Murphy , Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , x86@kernel.org, "H . Peter Anvin" , Jonathan Corbet , Shuah Khan , Shuah Khan Cc: David Woodhouse , Ackerley Tng , "Aneesh Kumar K . V" , Lorenzo Stoakes , "Liam R . Howlett" , Vlastimil Babka , Mike Rapoport , Suren Baghdasaryan , Michal Hocko , Joey Gouly , Suzuki K Poulose , Zenghui Yu , Steffen Eiden , linux-kernel@vger.kernel.org, kvm@vger.kernel.org, kvmarm@lists.linux.dev, linux-arm-kernel@lists.infradead.org, iommu@lists.linux.dev, linux-fsdevel@vger.kernel.org, linux-mm@kvack.org, linux-kselftest@vger.kernel.org, linux-doc@vger.kernel.org Subject: Re: [RFC PATCH v2 07/11] iommufd: Use large IOMMU pages for provider mappings Date: Fri, 16 Oct 2026 09:46:10 +0000 Message-ID: <20261016094610.57849-1-griffoul@gmail.com> X-Mailer: git-send-email 2.47.3 In-Reply-To: <20261016001448.GC14213@ziepe.ca> References: <20261014093733.90312-1-griffoul@gmail.com> <20261014093733.90312-8-griffoul@gmail.com> <20261016001448.GC14213@ziepe.ca> Precedence: bulk X-Mailing-List: kvm@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit On Thu, Oct 15, 2026 at 09:14:48PM -0300, Jason Gunthorpe wrote: > You are going to need to go into generic_pt and implement cut and a > more suitable unmap to make this stuff work properly. We can't over > unmap on conversions. Agreed. I'll drop this patch from v3 for now. Just to check I understand what you have in mind: a cut operation in generic_pt that splits a large entry in place into smaller ones, so that the revoke unmaps exactly its range, and iommufd uses large pages only on domains that support it? > Also please don't write commit messages with AI. WTF is this even > trying to say? The subject is "use large pages" and this text says > "map each page with its own call" Sorry about that. It goes away with the patch, and I'll check and rewrite the other commit messages for v3. Fred