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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?w+QjORv89oVsJS9FvtP7ef0elUPjtLXWBdxb29QCGJ/iG5T2dnneJf22PW3d?= =?us-ascii?Q?fptZ0IHsjjX4bY8Gp5UAMk9pzgdwcfnDO1ZtU0CK9UgFRGDXiYUgriJASNZq?= =?us-ascii?Q?X6kvGDIoJ6UsOT3Ph2bvl4Nci+FlhvU3eVp08lHkXymGsQJU9ivm4+CTAN/q?= =?us-ascii?Q?/dz22ew/DvPTksP8Zuo7J42fktaB69UwPrd0trS8YRSRWLmeJhhi1KwCwdCs?= =?us-ascii?Q?KTyc1NulEpFz70l4/5HdSi6PaveviQBMVVZ00Uah0Stm8ak2Werovy0tifw/?= =?us-ascii?Q?fuMI2I2MVzB0GyhZWQZkt6VH+BirtW3kTsYT5RLpHle/ue5qMrimGDJ+dw35?= =?us-ascii?Q?Du25QrG+qfFzHZMuIXBCLlKzZjieLUhnI7y231dnePj2TWvSjiesauRyAdfZ?= =?us-ascii?Q?Nf9hYGA1jiOE5dDSLcA0P/Hr7aND2ylPo6laXxbiWEnkI84fXMWZnt2VvOTB?= =?us-ascii?Q?XDAHA2zgM+FDwUxxdEyjmi6xdWW537CCkdIHFik/brpApzc9ia4PMrREW5im?= =?us-ascii?Q?MU4j7aMp4i+VYNUa5eoZcakxUZEmmmdnlI1q36BM2NEeEtIAlrBmjjUARaRK?= =?us-ascii?Q?fk0oS2wByVDTTv3Ju4okp7h0i5oCjT4MKuKokkMVCN5jLlN4+tR5QVpa4FJF?= =?us-ascii?Q?uEXXZtdwaSClc8+h8+m7JeTXpMJkn0Z8F7+8MtafT9B8KuGBS+t9Py2zvPj7?= =?us-ascii?Q?8q45k60uzRVWfKnYUAfZCK2gSVckPdaED2GKOOqf2sgWnyEai3OFQVwZuQmo?= =?us-ascii?Q?jylLUFLsxPkbCTqsy4g+n1wJ1w4rra5CGx1s6wqfg3oUKPhauxOjhqrDaxyj?= =?us-ascii?Q?J2171VJtjRswp44wLzv5uCbQd9HCGPnZXyDfiGgoRHWiSPeIALc5icuo3Ssg?= =?us-ascii?Q?75g4HtZeMLqLArREqzsjN3BQRl+TfBpcam9gzuCxwVSOU9J3TXJwSyuVpmpS?= =?us-ascii?Q?uyUreUvtMrIvg+peMFZxdLTYeDc5Jg3FxcObKtmiXcxNZ55fDf8wZSDGp2iE?= =?us-ascii?Q?iO/6cfqwQjeCygnPKs6I/E88V/l1gK0bHh5UY+uAm+ypJ++XyBBHsZ5frnIH?= =?us-ascii?Q?cKqYGavMyU7KZjE+dBCRrKr/7FkbcEAWbuVm3dRszr+gUWxYKDc4h3iDfww2?= =?us-ascii?Q?uEiWw8HeR2IGn6jkSbkvG+lufYAytlp8vGWcslzJ6Qii2Ux+LCNsjnwJJjDQ?= =?us-ascii?Q?jDYbUSPPIKvSd3iu5vFpDoG1CGLEuFt1k15c3XNWGt060nZwxlvg+1EPG9KY?= =?us-ascii?Q?BUq6Hu41wkzp2NlQ+Co30lmb5k+ZEvGeVcjiglTrlMV1Sc8FwjFo2HCkTbjO?= =?us-ascii?Q?nXBdmq9o4yJBNlsE5pdIPZrNyq60SL01KeqMj923g2K3DpiXhLeeUv4IUKAH?= =?us-ascii?Q?G5kcqwX4Bt2kkgFTVTw7c5FSYJvUbu3V20kswE8GUI4ZRIumkG4PijZSIwDW?= =?us-ascii?Q?l7i5vdU3+U+jxNu4dYtxgfoFWRqAbr5VIkVMKsW/KhldhbS2aD2OcOkb4Yrb?= =?us-ascii?Q?ZJTQ1ICHNR5PTnexTUyEFNgBErFS2qugucr6Kd0EeqBsI0nPiqYzbGx/B05G?= =?us-ascii?Q?8z+Xy2Mln09vDGYvgeA=3D?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 89e3c1b9-1c42-4c31-0545-08d9e5bf8231 X-MS-Exchange-CrossTenant-AuthSource: MN2PR12MB4192.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 01 Feb 2022 20:14:53.6494 (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: OQmIeegL7CLQqXttj8ae6KFbBB8NRh4u2xeoT9Tc7B4RG6j8UabvY5A+cKiroEjL X-MS-Exchange-Transport-CrossTenantHeadersStamped: BN8PR12MB3572 Precedence: bulk List-ID: X-Mailing-List: linux-rdma@vger.kernel.org On Tue, Feb 01, 2022 at 02:00:09PM -0600, Bob Pearson wrote: > as currently written the local variable has a kref obtained from the kref_get in > rxe_lookup_mcg or the kref_init in rxe_init_mcg if it is newly created. This ref is > dropped when the local variable goes out of scope. To protect the mcg when it is > inactive at least one more ref is required. I take an additional ref in rxe_get_mcg > if the mcg is created to protect the pointer in the red-black tree. This persists > for the lifetime of the object until it is destroyed when it is removed from the tree > and has the longest scope. This is enough to keep the object alive (it works fine BTW.) > It is also possible to take ref's representing the pointers in the list but they > wouldn't add anything. I think I got it upside down, but OK this works for me. What was kbuild complaining about? > On the other point. Is it standard practice to user ERRPTRs in the > kernel rather than return arguments? I seem to have seen both styles > used but it may have been my imagination. I don't have any > preference here but sometimes choose one or the other in parallel > flows to make comparable routines in the flows have similar > interfaces. Always prefer errptrs. Jason