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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?0dzmuESVdV6mq1ofobwqr+eNv3YHslu4SPu1CjKN/wKYqtaV2Zo0Bgrntya2?= =?us-ascii?Q?zBgWI+lgqIVYtYjNXc8sFRstqZges1CnFhIxQkoWOsFWh8RPkpUkl9zNlE/P?= =?us-ascii?Q?mg/hU5xk6cdghYIpPKdZPXWUNhfMYM2BrpW0bzkEZmdoou8l2SuCz6GCT4E5?= =?us-ascii?Q?1rXOaB+cABZs+qDYTRzKULhKo4WdCjFfCfn/3HcA9MDs0Alro6iD/YKA1nnf?= =?us-ascii?Q?olYTFS151mimvnNlr8o5J8BMGJtMKMFfU/1mwSHs5HCBhIXVzxaATSBJwfHR?= =?us-ascii?Q?oSrGKj4dZIRpGM8kR5JL3iXFB1oyDXqzBp74Ry2ly45PaDp2KvZPxk1kaxo2?= =?us-ascii?Q?Ux2HO1lbOiKXZ4cM7Ia3YGIneF/zOvsMkdOI4qnKBaebbaXxYnedRFzjDcEP?= =?us-ascii?Q?+P4xxF14XB/iQoWjIDYJ5obfU7lCsBnwKoB/PFiM7wpPuqHrHo/2PAde1Yob?= =?us-ascii?Q?3pb7T7S8jX2a/TaZi0p1dEUQPfQ7SlezkE9H2pgIKzFceFoKfKWPznollSBL?= =?us-ascii?Q?fR/iLsAecZemfmP9W0kGYRj19UYd7TLV7JR6LQCj4wI1LmTkYB9rQnXV3K39?= =?us-ascii?Q?z6p4mywGp2fEJfkZXSxYrJQr/0FyRU69Euis+wdM5gI2sZE6a4ltdaqIWCcz?= =?us-ascii?Q?EyHw96lBtxXBbVzHbDGXd+X+qmWAn35756H4t5BH9qW0lmHGTovjhRn+bN2C?= =?us-ascii?Q?1BGODUOQv1/LEiOvSFD9Oj3GU4lTn5w4pE7/Vl4uwvKsLt6dFEz+VR2w9Vtn?= =?us-ascii?Q?eWjyymxQqnT/iIn5QmSvoXA4qSJvye8SRCDdxz3D/+A3238+zeYxlcZeOGkP?= =?us-ascii?Q?S5JtV4MN/TbDpV86yc6vt6Jwelzt2eW93RiF+BA8tgNX4nzat8g+Rmq2/2ej?= =?us-ascii?Q?nZDcBSCvP2v5OQ4HH7T15pE5s/4CZjJ0m8R2JZWG1ko89n9CYG45YMsbXivK?= =?us-ascii?Q?qnfTZQk1+aeK5FQzlQob6nGYcIhcWPRSoA3sg2GjysaSVx6D4NRD333uJ88k?= =?us-ascii?Q?rijV+md6iqHgGvrWkjufkKGvAXRT9NSDZsO/dtaI21qH0S0Pw3YyIgyr8GTW?= =?us-ascii?Q?0zr4r/y0R3hIA6g5IRJ1cn0mygr7kFFpWUlGEMAn5qDLK0yyC16HKixUO6r0?= =?us-ascii?Q?AzWr/gAfr/Hbg8dnVhalXHMxEBN0AIUOT5kBJapcBHeCOxkZIVDFHIZreJuE?= =?us-ascii?Q?g+JW10zsT+tKiOdvgpLLnoQ9O6ROEncbwFuVFGIeYVJY8jU8PphdGCtB7hep?= =?us-ascii?Q?9ZlJViWgJJ302MPaPeZUMKIrQZv9TpsPzm7AQGYxbpe9ntgaOWbES3cmj5By?= =?us-ascii?Q?X3eO32vCCbXhFuS15r2ZpT3do+YMULRX+T8UH9zaMZLBjKaoE/HBNIy2P/o/?= =?us-ascii?Q?24+zEKUdPqdemSupyqOGYbeEm1ue77/YxV9DzhqpsKvuf3hmjqO0YsLyQttY?= =?us-ascii?Q?RR2ueuiN/7refSdgK2mVmYD79vHDN16FxuS17V1nSUWqCoi/Y3lY14fLVO4n?= =?us-ascii?Q?ZxtH1ygOjDvjtn2p1lMVrg133dUfxYMEAb8rE07Z0h45RWIAOXvbSr7rqDJ/?= =?us-ascii?Q?5Bxm/SgzsVZVgXBVRJdA0gLtvhLZLR81SZHK4Q1X?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 83a5d50e-736f-4b90-8e47-08dd3a7ab7b9 X-MS-Exchange-CrossTenant-AuthSource: CH3PR12MB8659.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 22 Jan 2025 00:21:30.1585 (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: L9cHtTAwjsmJBc4yKjCYXh+aYuX7MiP5RNd5HCxhGm4PRFV2kxVlJMeAqnrAjKrD X-MS-Exchange-Transport-CrossTenantHeadersStamped: PH7PR12MB7113 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20250121_162144_577058_007CECBF X-CRM114-Status: GOOD ( 12.88 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Tue, Jan 21, 2025 at 01:40:05PM -0800, Nicolin Chen wrote: > > There is also the minor detail of what happens if the hypervisor HW > > queue overflows - I don't know the answer here. It is security > > concerning since the VM can spam DMA errors at high rate. :| > > In my view, the hypervisor queue is the vHW queue for the VM, so > it should act like a HW, which means it's up to the guest kernel > driver that handles the high rate DMA errors.. I'm mainly wondering what happens if the single physical kernel event queue overflows because it is DOS'd by a VM and the hypervisor cannot drain it fast enough? I haven't looked closely but is there some kind of rate limiting or otherwise to mitigate DOS attacks on the shared event queue from VMs? Jason