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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?fdDIEsDsyfOJxmuWM/687xGohI07YZJFEf+XCw9lwGao0Gjv9Xo1f0xQ53fT?= =?us-ascii?Q?smohv0TCN8QrA3XE+CJ6o/AizgZ/zwP8FuH3gbheV3GCfeYYDcYkfJmZtKTP?= =?us-ascii?Q?MAN/932VJsGv0oqLUNB65iLV51bpSYQaXrKXT6J00cXQzB4hDwlPMa6jT171?= =?us-ascii?Q?I1p72nsoJDVH7utmmZcq+0iyaQWqjR1XacQuyilO3Cdbx9cLGz97bagLnDrv?= =?us-ascii?Q?xMSKlrccqwa+xPMCa+R0SziBMJj/qiPaST6zGMBhXfZUAvmB+8RfGH0y28Y9?= =?us-ascii?Q?Fr0sNTjPxDXl6ekxSEOWIjMoy9TJXdRfnd5mbjZx6pxFLu1JYNyKfu69VYBA?= =?us-ascii?Q?cy30/Azr1IHrIsIXC3dXLvMncKFLS7buihvCLhYMycNRt0k9TDjjfOGTBHlS?= =?us-ascii?Q?I17oQeQ4Oy1rroRAZGGtOGkICEA+98vKm/A6IuYFLz2Y6eYKWFQutKiKhe/e?= =?us-ascii?Q?dINCf9otpQN/fzmcxb348bQfMGItRiRbnpSnH3cYiiVYw3ayHmDmJGE3xEAy?= =?us-ascii?Q?BfCZ4SCyEj7b6zN1vhLBUkrx4s+b2ZKv9p3sIGSE7mFuuNFB3KiDM9vFWu+M?= =?us-ascii?Q?Yx2aaMZ2wYGX2n/efJJnqbuasGr3y+9Wiq8fJObqztRrZLFscRIUEK/F35jR?= =?us-ascii?Q?iJ6qV1ycpAEaj7CmYS3J2lUZkFjJNWWyOlYkJ1YNTsq6h/YNUV8HM8PSp/lO?= =?us-ascii?Q?3UCTkCgUJfR3Qi9x8EYrpDJNRoFqPHd14msIOS9HCNlj1Lli7yaRhGcEjQnI?= =?us-ascii?Q?jJ3mW5mOrgfT2cjDoew9VTG5bmgq5kMbhN7sNVdUmDtR/neHmYBbeXYdaU0g?= =?us-ascii?Q?/0VzshAr7PGBH9jFX9Uy1EzwBEhVMo+ex9ej5KxbBsnqqeUgwzILqHp3hPuv?= =?us-ascii?Q?zWFtPqr/n729EMpnb/m70IqAyALhjWjENUPB673rXzp3bg68cpvW+x/usDzG?= =?us-ascii?Q?lrT4usbXq2RhucBTkNkAovGW4UADlPOQsZCiX8uPKSX/raqF1+Dr5CjPjCdk?= =?us-ascii?Q?Z3kE6CBTqoH3Pg5mHL8RCa0rqjSl9xMMpWK70EsttG5FeCZ7R4VkRKH6Rvmg?= =?us-ascii?Q?loa8rSnF0SMZMlnQsElO9J7tOQHWoe+0s4h3ydFi4eEdVelBxL3YwRyOsfI+?= =?us-ascii?Q?yhNp63uCtA9fDhKjIjyeBaQPY2nvF2UEMO2SBkyjW8DKymsqXQ5x6f7O+lh4?= =?us-ascii?Q?ViJE2vyuIPWF1g7O5ukLXLhf3KvSd2Rgt/2mrVKPjkvEhmJn6KkaoGpbPX22?= =?us-ascii?Q?fJbF2GJ+dlu0VK0tRmGAuDVxCS8LzaRXthuJ373qCySvkvUX7WLhRvRth3YA?= =?us-ascii?Q?7f61JNjV/cWSxsnnSn6cLvw6?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 39bf7587-402e-4248-c6fd-08d94d1959df X-MS-Exchange-CrossTenant-AuthSource: BL0PR12MB5506.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 22 Jul 2021 14:02:33.1843 (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: Sez5Ii+gsVssSWgamB7+m1RcH376dBfHTpJu0c8Q3mA8rBs8gk5zaL4wO1+iH8hM X-MS-Exchange-Transport-CrossTenantHeadersStamped: BL1PR12MB5159 Precedence: bulk List-ID: X-Mailing-List: linux-rdma@vger.kernel.org On Thu, Jul 22, 2021 at 05:01:30PM +0300, Leon Romanovsky wrote: > On Thu, Jul 22, 2021 at 10:02:31AM -0300, Jason Gunthorpe wrote: > > 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. > > It can be, but it is not the case at least for iwpm. That is even more broken then. Structs with non-zero refcounts in them should not be freed. Jason