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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?PLXnfqdZunNQ2phTZuk9xgvLrIfc7B/a7F5MHLL9WuSttkY/ZbNRVT3TRXFY?= =?us-ascii?Q?4BSIsVqSnu+EloGOhThVyoSrnQH/mU/O4/pzoeDyIoFVKYTRI0wosmseI6Kn?= =?us-ascii?Q?yk+8ROEoNzPP1BgKLoCo4UzpAsMy9cOaXrT+6kMGZXvok18YyGNRPufXwYr2?= =?us-ascii?Q?YD4opGfmXqhEOo4tDhqXTfCiHw676pckt0+f+SKazlaF0xuFpY1BrFYKYZiV?= =?us-ascii?Q?g7bO+zpWnCvGGvAMVFNVqUKmMhCUHU0aGQPAsCXEr0EIN2VXA8ct5o071yg9?= =?us-ascii?Q?E5PSDAj+13Qgx5hNCKG9U1HPGhlS9r7CNmG74yXQGeVLwT0FBSq7wqD+Nyy0?= =?us-ascii?Q?7/T5KdvqvMNm/0vGgBjtqP+imIQGQClzFCkFgbqSjdJRXslUhQF/QdWzbC+Y?= =?us-ascii?Q?tZcylae6wm9gAAKa8VYFEFjgXkhkND+93GNOcpIQYN3LUnvwGYtG+KfmD4oI?= =?us-ascii?Q?uCJ0mYFulUI82vr8f9pbiN/19MEdXV1GtRSyKcNgT0CYjisRHW0CjdfKVTFa?= =?us-ascii?Q?qXXn51i31qut63/fjiVMYJ2FBiWLZVwNhBOKlWMmgiEh1HH2NVDH9hhnvd6W?= =?us-ascii?Q?aJBrRftxsunv1H6VHIF0XSjOrLSSTyjQpicQ9y2coxtFJF9j58ioR/4RyfTw?= =?us-ascii?Q?kvICSUMqzOWclEqZZEBpuKoN9/SLSLG9LiB0pMHYZjxkOzMnGg3uJj6lm6k5?= =?us-ascii?Q?/TDxB7vWO0uZaCj7z8BsZZA17EWcZoJSM5ZA4VE6shce0uP/SPZX1eQaWN5z?= =?us-ascii?Q?RB3p7Rr+jytSsAP+HeCp3PdusUO3r6pSTnmovYb4dmDQc7XrB1xfoNnlUQGT?= =?us-ascii?Q?fBR64A3ZjdjIfUoqVv+sZWKKzW7UJmFwDmfdI95cPKMVmsx52O1fVv4cbZTQ?= =?us-ascii?Q?8o3UDng5ccR1v9m4CcHHi9LsylYRLAIyiRi+fqZNlosQf7QoOuOtC/mUuJdH?= =?us-ascii?Q?vChhYwMA4JZet51vDzE8S7dZ5C5x0o6t9gCl+Ql8aaoqBBjrbbtIKpZEx3UZ?= =?us-ascii?Q?XxoT7ekID8fG9kZhuimI/zAmhbYREUWCISUuDK5JKDDcsRhWtkGwZWDAdZcW?= =?us-ascii?Q?W/7wIsTz627hdPGeWOwJC28MLwLvIMwZKgm3UV2tRupLL+i3lMQ/dcz6IsOW?= =?us-ascii?Q?jEgYqbJ56qN0+dv6vr35QeNJ0RbwyHZ0se29CSDjrEHm3A9T/b7XavgX5HTC?= =?us-ascii?Q?aJjtM8yR76fnNJm2LX10hdXZwZ/kE2rjSSEEWxK1xpJMmPPipF/RGSXe2gr7?= =?us-ascii?Q?AZxb6rHcg+QsfreKm19lscKAGuctzBtxwXO3BxvzHeJoPNoLs4h9ZoA1vAUz?= =?us-ascii?Q?M7kYcqFg5IVxlUOT8yKxuPyaaA8ayvtQMqCu9dBBNCfRnyQ75XYP9DEvxmnV?= =?us-ascii?Q?wRTX006keHIz8L+S3JNOlT01Ac0S3UKUg1ccwYMDWEBsqKCL3GSgjR0go75S?= =?us-ascii?Q?CDcInpRhR9TmjMwoZ5bNTKJvYDRqSURENDLRV4tPu7polemcAsgFQehW6I3G?= =?us-ascii?Q?PCmORiE1KuhvfLkFm2zzUfnKIuHFE9N81NjHcMAvNiL3x4iG9KVc7nV2pHuq?= =?us-ascii?Q?r9mIjrC7LEWE59H8XL+KkXyX6gqVj88CzcQzi1bO?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 6cce7dc0-ac96-4dd1-cc7d-08dbbb7ec53a X-MS-Exchange-CrossTenant-AuthSource: LV2PR12MB5869.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 22 Sep 2023 15:15:35.4368 (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: S+S2GnrkTlLVBGJ+KySGii7z4XHCWqen3+aY2FylOQ1tuF1dMDLplPn7ALtid/QB X-MS-Exchange-Transport-CrossTenantHeadersStamped: SJ0PR12MB6784 Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org On Fri, Sep 22, 2023 at 11:13:18AM -0400, Michael S. Tsirkin wrote: > On Fri, Sep 22, 2023 at 12:25:06PM +0000, Parav Pandit wrote: > > > > > From: Jason Gunthorpe > > > Sent: Friday, September 22, 2023 5:53 PM > > > > > > > > And what's more, using MMIO BAR0 then it can work for legacy. > > > > > > Oh? How? Our team didn't think so. > > > > It does not. It was already discussed. > > The device reset in legacy is not synchronous. > > The drivers do not wait for reset to complete; it was written for the sw backend. > > Hence MMIO BAR0 is not the best option in real implementations. > > Or maybe they made it synchronous in hardware, that's all. > After all same is true for the IO BAR0 e.g. for the PF: IO writes > are posted anyway. IO writes are not posted in PCI. Jason