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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?ZFyDSF+s3i5I5d736+/u8yws4dELlLe48D3zO6JdyzcPfoFQLXBEt8UQzNUq?= =?us-ascii?Q?+BoQjTYmRB/HJHmah2/d0YP1ufw25Bl42mBTJsxLouPGrMkAJHshGyF/pH25?= =?us-ascii?Q?Xvn0T6DFPTp+gubzWc5wjUta3Fo+pcvWAWCBRg3/6uNjrhHdY33I7d4hogU+?= =?us-ascii?Q?y9G5cimtuOLL8pqU+JeJ9cJxk7LKThqGmsjvob7TmbBa+M4Ay4iudk9Guf9c?= =?us-ascii?Q?r/LBg7sfie8HgmkeZHrfsj8UXJthVK2Sep2LaSBNdgiFzjSOJ6Awxkp1MKSM?= =?us-ascii?Q?Wtmy7Hjx/127rfCIsKU26wQJMLU3TPErImsrumDsawcEnrK1uRLS3kI1BrpG?= =?us-ascii?Q?sPSdjK3wlDwInI2gXVCk8p2jrNbcXCasgcud9AuW3Ar18izHnHWEG9IJeq/A?= =?us-ascii?Q?7GKoveibaykacU6ZI0PVNZfzUFm31oCLgKxMQi3GS2g+bP9vY21RZh6h2s1L?= =?us-ascii?Q?xOAjfEkGCIGCN0ittP5ebMFPAu0OvazHFABsR66ocG3TOZ+7gdBXysfRdSjZ?= =?us-ascii?Q?sJ8thDfAhimjpIgRqfHHCZfrxHaXLJcVpC+I5lRKCzfEM5Hc45ec41CeCesS?= =?us-ascii?Q?uPKk0zOVz2fbg2Dra28g2FKdnqRl/DXgY1vwLrj0YLjQI1qcAikjtQYzcU19?= =?us-ascii?Q?0AJqkdhC0jEmPXqWl46vscUt/fiOFZ/ABKeosFQ65Ae7+FaPsML+KAAcdkrs?= =?us-ascii?Q?gkcmAk7jD21ti1zQ8rFLbJj5bzhCO2ng4BLgx5S8wpLGqV2V4ooPMjiRQkKM?= =?us-ascii?Q?0B2vewNbHEvDddKBpD3SEnQHvdz6JtimrrfbSR2DJhtQlTJm53YrUo9Kak/1?= =?us-ascii?Q?/G9j5fCE7MqHzh0RCsKEobvLa9cg3p8lzgNB7kXz2FiSlXr35fmeky0cgdY+?= =?us-ascii?Q?n+Kbg86ZOtEErz5PoW6pfOJ6xXCN+CSAuXfW2WzHQ2fya3hBR7pUqs3f1xTT?= =?us-ascii?Q?Uac6ty/BGRvJjfKD+P5rfIiN8lxNYlsdwzon9UOil/v+jhTJnE7JiuWpfnm8?= =?us-ascii?Q?k3PYMUHrU9S3QQR+dUjv3MZDAFJKfOCxY+oO5tiPIwpnGEtpYvaXeUlCwyj8?= =?us-ascii?Q?JhqkiXtdMNBuQlZNoPZAvvr7umXwWkkQxchfJn6/XH0ykm9hExuxWB2Rqfa3?= =?us-ascii?Q?VKkFj2JoVDbMAqukllUIYWrld8w5Qi42phGDbWbrn/5QEpRblQsDkrE+Glaz?= =?us-ascii?Q?akLSeYRCVXVKpvAuR1cMVcxBAyhaIUMN8CemE/nJIci8xlWnvKLwpt51Z8XD?= =?us-ascii?Q?5Amgms2mvfn9y34enilSimupUNaFsilEYcGS/+ec6DQ1PMWTGcc30joVD0Oi?= =?us-ascii?Q?ya/cnPtzquDUNpYqwvR3a8YwC31ihDH+maL2pyOKlwcFDfa2tIyjSFtN3xM1?= =?us-ascii?Q?woMZGOTuCPtF+znoNdSsiovDbuf7zp1CT1huHalGPdPthe1kPw58mGniPEbl?= =?us-ascii?Q?5x+ZZRvZ7LQeIQFmi7VGQ/G/pW2OI3YlSiLwbTBV/qHCk9wc5LIZKLuVIUl2?= =?us-ascii?Q?sh5nPgGnlCPwjRncnXcK5CV2rKX+Qfg+32Q4OAbjp4ZhMIM545JWeUQ1BU52?= =?us-ascii?Q?w9yFXESXaNuHfE7UTvXH3kfquAddtpFJ0mcbPyMK?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 1acba4e3-4e6c-407d-1abe-08dbbadc7789 X-MS-Exchange-CrossTenant-AuthSource: LV2PR12MB5869.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 21 Sep 2023 19:53:46.5213 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: 43083d15-7273-40c1-b7db-39efd9ccc17a X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: 6Jm16Qn7Iq4793EosCBuuGQLAZvTnYJVGrRX749TA3lneXtRyZYyY56I8vGhxpaH X-MS-Exchange-Transport-CrossTenantHeadersStamped: CH3PR12MB9169 Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org On Thu, Sep 21, 2023 at 03:34:03PM -0400, Michael S. Tsirkin wrote: > that's easy/practical. If instead VDPA gives the same speed with just > shadow vq then keeping this hack in vfio seems like less of a problem. > Finally if VDPA is faster then maybe you will reconsider using it ;) It is not all about the speed. VDPA presents another large and complex software stack in the hypervisor that can be eliminated by simply using VFIO. VFIO is already required for other scenarios. This is about reducing complexity, reducing attack surface and increasing maintainability of the hypervisor environment. Jason