From mboxrd@z Thu Jan 1 00:00:00 1970 From: Mukesh Rathor Subject: [HYBRID] : mapping IO mems in the EPT Date: Thu, 14 Jun 2012 18:43:38 -0700 Message-ID: <20120614184338.43fb879b@mantra.us.oracle.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xen.org Errors-To: xen-devel-bounces@lists.xen.org To: "Xen-devel@lists.xensource.com" , Ian Campbell , "stefano.stabellini@eu.citrix.com" List-Id: xen-devel@lists.xenproject.org Hi guys, During my refresh to latest linux, I noticed, direct mapping of all non-RAM pages in xen_set_identity_and_release(). I currently don't map all at front, but as needed looking at the PAGE_IO bit in the pte. One result of that is minor change to common code macro: __set_fixmap(idx, phys, PAGE_KERNEL_NOCACHE) to to __set_fixmap(idx, phys, PAGE_KERNEL_IO_NOCACHE) To avoid this change, and keep all my changes limited to xen files only, I thought I could just map the entire non-ram pages up front too. But I am concerned the EPT may grow too large? Specially, when we get to *really* large NUMA boxes. What do you guys think? Should I worry about it? thanks Mukesh E820 on my small box: Xen: [mem 0x0000000000000000-0x000000000009cfff] usable Xen: [mem 0x000000000009d800-0x00000000000fffff] reserved Xen: [mem 0x0000000000100000-0x00000000bf30cfff] usable Xen: [mem 0x00000000bf30d000-0x00000000bf38cfff] ACPI NVS Xen: [mem 0x00000000bf38d000-0x00000000bf3a2fff] reserved Xen: [mem 0x00000000bf3a3000-0x00000000bf3a3fff] ACPI NVS Xen: [mem 0x00000000bf3a4000-0x00000000bf3b4fff] reserved Xen: [mem 0x00000000bf3b5000-0x00000000bf3b7fff] ACPI NVS Xen: [mem 0x00000000bf3b8000-0x00000000bf3defff] reserved Xen: [mem 0x00000000bf3df000-0x00000000bf3dffff] usable Xen: [mem 0x00000000bf3e0000-0x00000000bf3e0fff] ACPI NVS Xen: [mem 0x00000000bf3e1000-0x00000000bf415fff] reserved Xen: [mem 0x00000000bf416000-0x00000000bf41ffff] ACPI data Xen: [mem 0x00000000bf420000-0x00000000bf420fff] ACPI NVS Xen: [mem 0x00000000bf421000-0x00000000bf422fff] ACPI data Xen: [mem 0x00000000bf423000-0x00000000bf42afff] ACPI NVS Xen: [mem 0x00000000bf42b000-0x00000000bf453fff] reserved Xen: [mem 0x00000000bf454000-0x00000000bf656fff] ACPI NVS Xen: [mem 0x00000000bf657000-0x00000000bf7fffff] usable Xen: [mem 0x00000000c0000000-0x00000000cfffffff] reserved Xen: [mem 0x00000000fec00000-0x00000000fec02fff] reserved Xen: [mem 0x00000000fec90000-0x00000000fec90fff] reserved Xen: [mem 0x00000000fed1c000-0x00000000fed1ffff] reserved Xen: [mem 0x00000000fee00000-0x00000000fee00fff] reserved Xen: [mem 0x00000000ff000000-0x00000000ffffffff] reserved Xen: [mem 0x0000000100000000-0x00000002bfffffff] usable