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mx.microsoft.com 1; spf=pass smtp.mailfrom=citrix.com; dmarc=pass action=none header.from=citrix.com; dkim=pass header.d=citrix.com; arc=none DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=citrix.onmicrosoft.com; s=selector2-citrix-onmicrosoft-com; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-SenderADCheck; bh=cKFk9O7qIhJQjZvK2iwmn2evIFBeA8AxkEvFqmx7VMs=; b=mo5liVbs881p7WIb9n7JGtSVLOapm3d5xlJ2PhWzS0nvJah4Kd6wajkffoO1j/ZgxatjStLD6oXdWBMOW5C6moanwEmx2EN7Ps8RPk4SyxCzJThZCp5pvTQ6lxYk62XCVnF68c0T+np1c2uVgClTh/88hfeYtsq2eOxfzK0mr7Q= Date: Fri, 10 Dec 2021 14:53:38 +0100 From: Roger Pau =?utf-8?B?TW9ubsOp?= To: Jan Beulich CC: "xen-devel@lists.xenproject.org" , Andrew Cooper , Paul Durrant Subject: Re: [PATCH v2 11/18] AMD/IOMMU: return old PTE from {set,clear}_iommu_pte_present() Message-ID: References: <957f067b-9fe1-2350-4266-51982f09d3a9@suse.com> <33819694-2787-4bd6-1830-6b4eb81cb4a1@suse.com> <1fe2b37d-b898-c86e-dd4a-482bff9597db@suse.com> Content-Type: text/plain; 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First split set_iommu_pte_present() from > >> set_iommu_ptes_present(): Only the former needs to return the old PTE, > >> while the latter (like also set_iommu_pde_present()) doesn't even need > >> to return flush indicators. Then change return types/values and callers > >> accordingly. > > > > Without looking at further patches I would say you only care to know > > whether the old PTE was present (ie: pr bit set), at which point those > > functions could also return a boolean instead of a full PTE? > > But looking at further patches will reveal that I then also need the > next_level field from the old PTE (to tell superpages from page tables). Oh, OK. I was expecting something like that. Reviewed-by: Roger Pau Monné I wouldn't mind if you added a note to the commit message that the full PTE is returned because new callers will require more data. Thanks, Roger.