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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?NhjQGQ1y0UolOJ7dBWMaAT0YBvgVW8xbcSsxogaNu4tF6r+8zMzEor9fCAJ1?= =?us-ascii?Q?zRrrxLE/Fwp03k9MG9Q25wg40v/AMuNGx53Vz8xMnyccimTCrM7FcxC55sHV?= =?us-ascii?Q?VgGABIf8iowFE7NoTIbckXNp5GJTB7e/58MbKZ9REbLsMQsnTWvwdTGkKRu9?= =?us-ascii?Q?PCZkMmuGvPAJb1hlKc42FoSSgd9gURtfzw2lRQESQwyT+Cxxhirt/KqE5199?= =?us-ascii?Q?VzZbAEkXl4kll68h+2eLqZ7+0qg69+dqjNaBG5GfBSGr4ggAd6XGIFBV9Xbc?= =?us-ascii?Q?qBPLDEjJ8hVkMqx2hC6K1FPQWLFr0rvccZUVPr+gy+RlUPYFHgs1p5oag48K?= =?us-ascii?Q?B8RwKV2L0Rd1DaU/Y7YM7+szjaJ3pyf34RoEYXG1iYg77dLN0YJSrydiKXFt?= =?us-ascii?Q?lpODHJgfh6fIwc0lkwIYrScC+/7gwJh7Oj30z4twS0r6nMFHNoPLyZmRs0Te?= =?us-ascii?Q?DmTipnKBe1ObBbEOU13AnbuNqbO97L1wMRxn6LjQPOv2QHM07qQJGd54NfZA?= =?us-ascii?Q?gsH2adeH2tvwufs/3BXFD7mBVbqLeHg9rS6Wb2brAkaiezN9UgRp38VjCYYh?= =?us-ascii?Q?LnrOwpYoCBs0xpS6AEFBg3J8fE1SDrfAzDIdz9NWn2jPMaXGRVKNGcL49mn7?= =?us-ascii?Q?5PvQaB45jbWSwSaWsX/UUzw2Oot/TS296r8SqWUANuOxIR/Benx1TqmFuTAm?= =?us-ascii?Q?yAx9y0uTDVmZhnO0so/DFxTO7yvdHWkkk1NsZQXWMD3i1B73q3bjcjb9pQeO?= =?us-ascii?Q?fmpjlT7TThs8MPnXDUCBUjc9CKiYXcAh+j3iObYNe4WAywkILtQbzr6zFuTA?= =?us-ascii?Q?tmgnBWEoxx+azmJq+zw1kfWMX0xVMbonbP9uKek23rdqn75NVnWCDfwIZPE2?= =?us-ascii?Q?agekTor6FILG3CX/ggYfiq/ixoa3B5PaVG3LfSHVCp12OKxo2v8y333Wuruo?= =?us-ascii?Q?zlWmQ+IDG7b0pMgt+yhge1DjhT7TwTx/Bp5aU3XJ2FGXizrT8pq3ZrJpIB95?= =?us-ascii?Q?4gfWfc2CQoEBShYVRQnmhAvbDsjuwdqgk7ofTVt90mjhrAiMyUEjPRDhcRlM?= =?us-ascii?Q?iU5afyOtDIWo34UmgxU45lDAvtb4sWozex5HRgLhbr6tZPEiR7NZYmRHO7Rf?= =?us-ascii?Q?TmGogJHpZSJ4Ua+mIYYvjE+Pw94y31xOXABjEb184HPek2Byu9e95EOgTYL0?= =?us-ascii?Q?LS629SHPD+FIMtM6ZWXWuNyQjaVAD2mE9JjGDqHpBuBKKJujmepgtFSBgRTu?= =?us-ascii?Q?xY/kltCS3Zv5RIusCysoMyViokPy0ZYtUrr0bpX9V6cqhWMBTw+gammI5aTL?= =?us-ascii?Q?rjxH6CW0uRwOmCxVxeE4FBUm2Mo+Am4aLfiVcmXNDma3S/8ohJ249wuNg1Zf?= =?us-ascii?Q?y3ArEsteL61bzUKt67f2YJdLOBBtyclmLnCdICG/ACbx0rsy7f4JvNCMS/mT?= =?us-ascii?Q?4suYxxfGH0c6Dfjp7TMl8SD+3L6tUOuJBXA+NytYOjhU11nOkbSzGbk705r0?= =?us-ascii?Q?kjC0hb7NCogg3bGq8C8mIxbyN68vcRVQmtTGJWQuNir7praPphlL892q/G8B?= =?us-ascii?Q?5Xg40yOKu6IXLWEolPk=3D?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 7901968c-149b-452e-8730-08d9fd187926 X-MS-Exchange-CrossTenant-AuthSource: MN2PR12MB4192.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 03 Mar 2022 13:19:40.4652 (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: xFQAUpdB35HC4Cf9QG4oO/SJb1Cp9ioBycmp2knFdi3vRyboFU0Rk4KRpn1qZLD9 X-MS-Exchange-Transport-CrossTenantHeadersStamped: DM6PR12MB4300 Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org On Thu, Mar 03, 2022 at 01:17:05PM +0000, Shameerali Kolothum Thodi wrote: > > Tthere is a scenario that transfers only QM_MATCH_SIZE in stop_copy? > > This doesn't seem like a good idea, I think you should transfer a > > positive indication 'this device is not ready' instead of truncating > > the stream. A truncated stream should not be a valid stream. > > > > ie always transfer the whole struct. > > We could add a 'qm_state' and return the whole struct. But the rest > of the struct is basically invalid if qm_state = QM_NOT_REDAY. This seems like the right thing to do to me > > > Looks like setting the total_length = 0 in STOP_COPY is a better > > > solution(If there are no other issues with that) as it will avoid > > > grabbing the state_mutex as you mentioned above. > > > > That seems really weird, I wouldn't recommend doing that.. > > Does that mean we don't support a zero data transfer in STOP_COPY? total_length should not go backwards > The concern is if we always transfer the whole struct, we end up reading > and writing the whole thing even if most of the data is invalid. Well, you can't know if the device is not ready or not until the reaching STOP_COPY, so you have to transfer something to avoid truncating the data stream. The state here is tiny, is the extra transfer a real worry? Jason