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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?t7d+g9ftxU9AKeDwJFAZ2r/VUdwxJXYpTuKeZc/dpUlrQoyOmnz+rLsBogiz?= =?us-ascii?Q?aGJlUYPZC5HakxYXv8Oa7TsS8KSVXVYbZsEjs/MGakQq8AGIjAwsaydgDLmX?= =?us-ascii?Q?IzUYfGtdJ+Lo9ptixGd1VjTYyTPw1aKCfULG0j00t0RWImjdajgfPyBL2qOj?= =?us-ascii?Q?bSRinYgP0oCFXJVds+SVWWPOP2ma4dO3lj6khbSrlrsjsMjHpxDOtR/VbzDx?= =?us-ascii?Q?b/NWi5HaAQ9uycHrlDfFxuozohMQUNihE6GZKrSeQAd+ba9OWNZcLDJ9kIxZ?= =?us-ascii?Q?wOJ44CCu1qI3ObH3SoqiYnxqUdaLdbGuBEWCg1Vts97r0t7ClpRYy6FgV2xK?= =?us-ascii?Q?hzt7nwzUIFUqyj+zaEO3vIbBI9dYgj5FkBiHfYODPXzsrOLIKUI07WnjCBN/?= =?us-ascii?Q?3pW8EtytHw4SvbhZMfomFrGAz24fwxo2xHHK7QtlMTyt3oEbpPpcBC8K5P0y?= =?us-ascii?Q?QUwrPNagnhNkY7FG3xHhxun4KBbEevonxdKcolokcQafWPX/Oc/aAgEgrGCX?= =?us-ascii?Q?lYZKKuXD8U0RHNV/6UiT2LuG6AQHzjzrcYCRjKKIpe7jQtsE0sq6S2oEa7mb?= =?us-ascii?Q?/InZeESk2/JxCMPYOtxZJGkAPeNKg4vNseybd3Rjh708aWZ6quj1w76T2iD/?= =?us-ascii?Q?lnbaaIM9yUYouFlNRNqaEtGiNB5DjbMfLego0/UkhMChU/x0vlUMhiQSh/xQ?= =?us-ascii?Q?3rkDZ93Dnrak6TZoh8nu8eDR9doRcY+GuqA9t86ayica+Tm+oFQVXzz0+d6K?= =?us-ascii?Q?7/2p8wcwDhMkqvvCyINboRkCI52+wBNmcJidwPCH8qMl0C/+bJ0g3RVChYGe?= =?us-ascii?Q?pPU7u+i6zvELt3/h1YJ2X3GGVj/5VR+NQhpnnrlR5TGsd2+nokpV7TZbtNa5?= =?us-ascii?Q?b9m2z+T5+tL/rA/TjdilXfurtpmcJtFUi/zEF5f+i4qMxkT4Zjz6I9EWyVFQ?= =?us-ascii?Q?VHl+U/mlnqnPAwNhweWy5IJu5kMLfEfRgY2m5equWKdvNiIHCcZuJ9Wzvfur?= =?us-ascii?Q?Tn8NdMLW0tsLikqNHW0HME6pQrYLJX40Xp+iYbcB8ZKHJ3ld2dzYvfySP6lK?= =?us-ascii?Q?GUnbK8cs2QlsnEllkAfMRhC4Dj584CmW7S9ys0MhedYk5yPuPnm+azIFKV0G?= =?us-ascii?Q?uRKTv632EN/ZQMeNgwoTFFZvjnrh+Pur8QjPrEhnF6aUklqCYVAsj5e+M9QP?= =?us-ascii?Q?Dxl5Jz5/U//5Rjbc+JxSrH2eoQ1KC8cifFIp8aBanlkv2/48FjKR2rd58miL?= =?us-ascii?Q?F4GHAWM3aqCPqxB4sS/zjUwJyRynMB2yYhEVxf7cUFTxZq380POugAx7Iefw?= =?us-ascii?Q?KFdwgtaB3WPxN4HsF//UaDACzS01BTNYROlFtK0LVdJdukU40huevuqlJFjk?= =?us-ascii?Q?gVKv2dtVnP1oJNRwfyp3V6NXxZZaK1/+Sz0iQ6HXAQoeKhcI2wq3lILjdfG9?= =?us-ascii?Q?YFaNoWJ+KtrKn8UPEyO6EvtfTsNaqYXVCyDJ0TK1daryNZ6v+LNRowTVpUTX?= =?us-ascii?Q?DIpVn+FjrcqK6bDjIgYoxE88ZeKvYNFfnbbVMVWUxESOf8OQG+UHcumWOiZF?= =?us-ascii?Q?4O9Kr/xQwLEZM4JnXmrCptHwijRvsV7LuqleRclF/Q8I6fc5ikqFeHyPbLsu?= =?us-ascii?Q?tQ=3D=3D?= X-OriginatorOrg: memverge.com X-MS-Exchange-CrossTenant-Network-Message-Id: da0f2e86-ff77-4100-0695-08db054f154f X-MS-Exchange-CrossTenant-AuthSource: BN6PR17MB3121.namprd17.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 02 Feb 2023 18:55:42.2050 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: 5c90cb59-37e7-4c81-9c07-00473d5fb682 X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: VkLfY+UpINXbRSn0CKdVYd2SKJ3MeHzYx/Dd1WtARo6t00PgvEzxcuv5XYYipXSdLTe5TXLpZZcUUa1NRhcYf57aLtBYRgTihaBVUQ17eQ8= X-MS-Exchange-Transport-CrossTenantHeadersStamped: SJ0PR17MB5053 Precedence: bulk List-ID: X-Mailing-List: linux-cxl@vger.kernel.org On Thu, Feb 02, 2023 at 10:18:33AM -0800, Dan Williams wrote: > Gregory Price wrote: > [..] > > To me, the solution here isn't to change QEMU, it's to change the kernel > > to try to get it to aggressively keep executable regions out of CXL by > > marking CXL regions into a new zone type that essentially says "Use this > > as a last resort only for X pages". But that would likely require > > adding migration code to the likes of mprotect and friends. > > No, this can't be the path forward as far as I can see. QEMU is a test > vehicle for CXL enabling, there's no expectation that QEMU is running > CXL emulation in production. The quirks of how the QEMU-CXL memory > behaves are not something the kernel should worry about mitigating. CXL > is "System RAM" especially in the case when it is mapped by > platform-firmware. If it's not suitable to be treated as "System RAM" > then the onus is on platform-firmware to keep it out of the general > purpose pool. > Eh, you're right, just spitballing. On real hardware this isn't an issue so there's no reason to change the kernel. QEMU should just model the hardware.