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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?R/SDVNbHzn0Am3VjxgiryG6Q2ko5ET8cnA6Z+WUMHHEYa46GddhoHPy7bmFN?= =?us-ascii?Q?r8aG/4dZwJRfwY4AThwZdshikBIxmeAaI3KJZzBISAGQn1eZm3qzmJK+4Duk?= =?us-ascii?Q?LUeM0lEiEV7LpkALN1ZNA2OT/DmSXzlK+xI+2TYkQPUIZnDadR6r1pavIcz+?= =?us-ascii?Q?kWThEyX9Uxm8Y3XlPuPQHgdk6OSERDohyuYkuH1CuFzmiwtJ+k1uh3Mwfbgs?= =?us-ascii?Q?uN3yO+c+ImM+C5EkzpArr9ZT8AmVAHEhz4JQpACzsEiYmdfwCvC3RoCKqRi3?= =?us-ascii?Q?HdpmAqhM7b1amVAPGk7lM/v7RDRwY8pnuMFko6dZdoD7pmBJma8g7TFQgw18?= =?us-ascii?Q?kgAmFLzVCaWnwfJVDi4tVs6emfKYDjQztx4S3PQp39vstLYibxvhjtWOMeVE?= =?us-ascii?Q?z4mEsF9B93qbpTWHKAiXDwaUUPqjX1Hhq1zLQU+wSHjr0uM4t6zKnCBZT+1l?= =?us-ascii?Q?WkeJfmk2AU4tVbgLgncl/8m3MXPmrimn1aU+CtbF7pbStPlAUc8GyYegKYbq?= =?us-ascii?Q?EpaKst9BdTLz5N4NRvwHFumlu4UDq0xd1q+Jn7G/96grNkgHSOiiifo8zMOh?= =?us-ascii?Q?oSi6kSB89ukHofApc87coI490VpZplcPg3l0wf9t+kEj8iXUf2HNtAxaG4fw?= =?us-ascii?Q?vxoG3R2LYWShb0qX0r11ua3xaazUoHK9Pj6tBW0zQI79BhVbFdrt21ylnGRk?= =?us-ascii?Q?T+y5VyfPbiGtVR9tN7xqLrSNKrw0v0Th1jml0wlByHb79aaKAykyKgyYRczE?= =?us-ascii?Q?XH5vqfiwLY5gkn0SdSmcoguC8JuKJha6oNKb6Tdm1W+zn6keyZWOfP1umIls?= =?us-ascii?Q?plvhB3ZfO2WDMW+h49FccKR6nfCc1B7NwV6rI3YXePskKBd5lB6wWYAJeke2?= =?us-ascii?Q?GxGXFx4VnknmovdbFTdgwFvl2dL2o1ST0+FQA2/iy3jJZbBrlP0xVrffrwbY?= =?us-ascii?Q?56lcLDh5ytQKdBn/bmbh6h5jeuf/rOyv/GXZxpx0u1v6xapFAZlmaaqWmf1T?= =?us-ascii?Q?3MDGKjV/BxnYiKx0xxuoFfMkEDeZ8+Od1id3rzDreCZqsG+GBPw01Wt7EKCz?= =?us-ascii?Q?73RlrRNGETdtRL/r5Dr3FT7VD3vldLkdWHqwi1T4uMJtq4lwUGh6nFrLtK6D?= =?us-ascii?Q?6cUSa2+jPZFcn+sKznAvzrmTXFkwP+ux4VSdSnwh0zIvvAU9sjsRrYQCSOKi?= =?us-ascii?Q?/KptaZYiJGgykyouma8FgTt25P2KsacFogYOdoer4LBaHP7TY9WUknPxI8Xz?= =?us-ascii?Q?maUeOv16KSnH774egTODQRAWLhgqyqDRBHMR8uObByi4thDAYeaz2xN5nit4?= =?us-ascii?Q?YJeNbivV81Ekin9EauaKs8NO?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 4dde7418-2b33-4451-eeb7-08d94d10f822 X-MS-Exchange-CrossTenant-AuthSource: BL0PR12MB5506.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 22 Jul 2021 13:02:32.8505 (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: 1EUcVWia/JRP1spYWKNEAz3wGqe9ZVQ45A8tM0r+ONE2adZ4O+791cmhlyPzrP/j X-MS-Exchange-Transport-CrossTenantHeadersStamped: BL1PR12MB5238 Precedence: bulk List-ID: X-Mailing-List: linux-rdma@vger.kernel.org On Thu, Jul 22, 2021 at 03:57:39PM +0300, Leon Romanovsky wrote: > We are talking about two different issues that this refcount_read patch pointed. > You are focused on wrong usage of completion, I saw useless compare of > refcount_t with 0 that can't be. It can be zero. Anything that does refcount_dec_and_test() can make the refcount be zero. The issue here is that refcount_dec() cannot make the refcount zero as it is improper use of the API. Jason