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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?j/U/4T66PgFDL5j0uxrw5IVsg3jLCeloWO0M7eW93WHzi5r8TgUSJnVQb+rx?= =?us-ascii?Q?jw037og1FG50hwgvFhjfRmnBHZRSW6m+rqYnPxa+QRC5QUIMKWxgfUABNkaY?= =?us-ascii?Q?AuQmgI2/gFBTsCUVICgErefAYtBUatD3Vu24+tWlpsPeja2p1LJzSXvj0jOf?= =?us-ascii?Q?YtLh6BJ39PakNmgdadV3vFBwkreZNfgL1qht9ameXV/gU+L++a0XSRUHiGUj?= =?us-ascii?Q?hxJ876YXRWzpwknSdwojqM2p9EbGvu67waqR1bEHi+55p8sLpufJOt4EB1iL?= =?us-ascii?Q?18BsyOB5lDIwBX2V/frRuB6wvhGT5DlDdomRBquu7jPYDMxH8feA+DL4TGKR?= =?us-ascii?Q?gfqmZKzHo98tyHWwytnelpny1o11yhZ4eZLFoLEkkLCQSpPXYUwGlGnuzJ01?= =?us-ascii?Q?epyPS124b15v3wSNFZJplI9I92lP2rwLk6jKPWnCju8YwDhbuEincHxTi6ze?= =?us-ascii?Q?NaGUjCrRO2Y2UkjOV35dym5yWCbBsiieOKTCkCTnEYEQ55ZTlG8WFpCH3LQL?= =?us-ascii?Q?P1oF4tRuL/1hVNuseMxnteSH9QZkvnkZrjAGHNr66KNRsTUysVDgWCwjwH4U?= =?us-ascii?Q?++/k9TGdKdwoEfk/zhXhsZA/HsRhRvH9mGS7328S5+fGbLDdKfMPa/AMlMwn?= =?us-ascii?Q?yw1+82w5eEhTFa00ikIQu2GUZs5hJ2tGJc8aDy4ujszSnCDYR8u7ypTj0bxy?= =?us-ascii?Q?7LJAdhpuRUfFnarwgmLi0WwEKpHxp8IkqNCDrjjiNuvxrxQZN//6L7qnKTla?= =?us-ascii?Q?/HFOUGWNbH8NK88ugY0stGfAuOd9li1JrA3EKOZ/bBuYxWYbVIQtisME7giw?= =?us-ascii?Q?ATIBYJegVtW/O2QRHN1QxnUOKk8EVPVjXOXi501vXBl6Q48i21Rt9DbWFKS2?= =?us-ascii?Q?k9ouKjhL3mng6MFy99Wx3DmrO8uc26vhsUGgYhPpT6d1wkN65Mc1nWxb3LKE?= =?us-ascii?Q?ne38nBDVLJZL/8mhF3tFCN60B/JVFicXdBYMo3QFedLPN53md8HrlbKoVonG?= =?us-ascii?Q?dfMI9FaBI3u14cPoax6KMgmXGYkDa18hARXJ6t60CeT5yrNWRuPK18b4nTP5?= =?us-ascii?Q?UJbYUNHbwXkk5Tp+Csvc2vjSmlsvziVn5xWJlV6qFrzMUSIZPAr3zfJJeeu2?= =?us-ascii?Q?7f7OA8M3UdVh66jBuo2vqQoVCv0lE4R+Bv1yTZZgt6AsDBShA+DLwHcvIsTH?= =?us-ascii?Q?+GlhzNGmRBcv0Jt3nLU3VaB8wLtqukt6iFgRt0euytnX2PLz1goZhqqV8qwY?= =?us-ascii?Q?cSFUGX8k5VvXPc7Qv3uGytePynk20AKo5+EV2SJm9DhrhHSuU5KouB3A2ZCH?= =?us-ascii?Q?Yzu0v/ZU3fG0u8OomGxtqoEhQPvke9hJ/1dwFCrBT8YldZh/2IusFh6uJyrO?= =?us-ascii?Q?NnDscmdo4uMRbmVxr4XPhEAawpSdXfh0RUqOK6xSG6D9JnMsFRLFjckQmcLJ?= =?us-ascii?Q?wvituZiWA2J6fJ09chiHQN75Y9TFGmmpb54mXmUJQ8WXDWgSCxpz3R5RaLgm?= =?us-ascii?Q?NDKgPOiiOXamTW7NKxFdbhfN7bdVZdzYq7bAXBmfcdp79be3Trp3hZuWwRhm?= =?us-ascii?Q?HWXvusCEuQqrlsr66/Bk5mHQCYH2FLhnurOrIiV9?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 52a2ac39-31c5-4e87-eae2-08dd31b024cc X-MS-Exchange-CrossTenant-AuthSource: CH3PR12MB8659.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 10 Jan 2025 19:51:15.9095 (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: KM/aE2/VHM1BVncU4i2at0KeFA4yhfbQWnR/RkVpdRuAkvHlm85BNwxXRfaBpd7R X-MS-Exchange-Transport-CrossTenantHeadersStamped: IA0PR12MB8302 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20250110_115122_251688_331D5121 X-CRM114-Status: GOOD ( 16.99 ) 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 Fri, Jan 10, 2025 at 10:38:42AM -0800, Nicolin Chen wrote: > > The virtual event queue should behave the same as if the physical > > event queue overflows, and that logic should be in the smmu driver - > > this should return some Exxx to indicate the queue is filled. > > Hmm, the driver only screams... > > static irqreturn_t arm_smmu_evtq_thread(int irq, void *dev) > { > [...] > /* > * Not much we can do on overflow, so scream and pretend we're > * trying harder. > */ > if (queue_sync_prod_in(q) == -EOVERFLOW) > dev_err(smmu->dev, "EVTQ overflow detected -- events lost\n"); Well it must know from the HW somehow that the overflow has happened?? > > I supposed we will need a way to indicate lost events to userspace on > > top of this? > > Perhaps another u32 flag in the arm_smmuv3_vevent struct to report > an overflow. That said, what userspace/VMM will need to do with it? Trigger the above code in the VM somehow? Jason