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[142.68.80.239]) by smtp.gmail.com with ESMTPSA id mi23-20020a056214559700b0069b4cc9780fsm3071361qvb.2.2024.04.29.07.46.24 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 29 Apr 2024 07:46:24 -0700 (PDT) Received: from jgg by wakko with local (Exim 4.95) (envelope-from ) id 1s1SGt-001ToN-OO; Mon, 29 Apr 2024 11:46:23 -0300 Date: Mon, 29 Apr 2024 11:46:23 -0300 From: Jason Gunthorpe To: Matthew Wilcox Cc: David Hildenbrand , Pasha Tatashin , akpm@linux-foundation.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org, rientjes@google.com, dwmw2@infradead.org, baolu.lu@linux.intel.com, joro@8bytes.org, will@kernel.org, robin.murphy@arm.com, iommu@lists.linux.dev Subject: Re: [RFC v2 0/3] iommu/intel: Free empty page tables on unmaps Message-ID: <20240429144623.GN231144@ziepe.ca> References: <20240426034323.417219-1-pasha.tatashin@soleen.com> <2daf168e-e2b2-4b19-9b39-d58b358c8cd9@redhat.com> <9bf62e97-dfdd-4537-8fb0-b5f293856f59@redhat.com> Precedence: bulk X-Mailing-List: iommu@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: On Fri, Apr 26, 2024 at 08:39:14PM +0100, Matthew Wilcox wrote: > I think there's a lot of space in the struct page that can be used. > These are iommu page tables, not cpu page tables, so things are a bit > different for them. But should they be converted to use ptdesc? Maybe! Definately! Someday we will need more stuff in here.. Jason