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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?6jZVDMjf30ynMHeHM1EaKYhZehuKuoRYHfhFzDy8G0zimIssqSOSD+55IJUl?= =?us-ascii?Q?FhPpvlGXCYXvoje2lf4fjwFv9y/a6+iDcNkV8Z1qpAL89c4AjAMadBGDUzdc?= =?us-ascii?Q?y/hAPpacNCdP3sILMfeWx3wX4krMyP/Hq9R5OzozFtPpQ8dNT8gYB0sSzs+H?= =?us-ascii?Q?BWcDyrtggBVtnxIZZc8ossJOf7Hn5bslS4jyp305WqSQW3PzqpQTx/XNeOwS?= =?us-ascii?Q?u7kVuoq3mUdPgL3Uv9jUllj7HLPVcC8iKY+Z6s6FKm8AFvpIU79sQnX7J4SG?= =?us-ascii?Q?SFC1SPQKUm5QZ99c1JVbCEkJz/ULuL3y5We/YNVuiYB6/94QUw9xfXAH9mOv?= =?us-ascii?Q?ybnEQxny1PWlHgPQU0UUecjB6qAcZ5F/57wFUttyMJAE4o0jWQBvk4afIs+M?= =?us-ascii?Q?LTJgIbt8jf3rjyXWCWLZubN14MncRfPZ85CbRovV6zX+DFsZMrDp2pzZpYbC?= =?us-ascii?Q?r7dPUDvursCf8ZeeMp6UkJRacNqaX8ekqLWUKPgwpGNjg0UudJf1ru4SYjd0?= =?us-ascii?Q?U2WxqrBvSqgUU5nwQXdqgV2bBkGnEQEzRvB7a8YaKOPtGg9XHcDlV+eoLKH4?= =?us-ascii?Q?LD6wV0L2yC6iAHO4AWA6l4/TTJwNaFYEa3H141My9ukt7UisaSTx0DhUqj/a?= =?us-ascii?Q?mdWPy9Vvi/egNWhxW8TXbl4BUtechk2KEWtrpUgkuq/b4mNcSecE5TLMCIMO?= =?us-ascii?Q?et++c8H+GaSgiKi6CrE7MXIXn/nCNCCKdhL2jYhleowHDL+42JHgejwVaRL5?= =?us-ascii?Q?KxpLT18mJ+/aifvCSmkJ1dR9Qdq0/KZH2GVEEAguFT2hORT39fYb1zShoAZb?= =?us-ascii?Q?HX4WwkMMy736pIemiVYJydgsO612JlULClPaTtcWSFD6KCNWwM3Vc9snhYey?= =?us-ascii?Q?D8NOR9gF+emXYEWCQPMmaKNkkS+zMcKoyZuz5qZHjJGSGL1qOvtFr5h50EvM?= =?us-ascii?Q?/zSYQ0ZTdVE3dah7tJdcGf70QoLmKwmcJgeq2A1tFMLbGlCm+bVIj6beW41X?= =?us-ascii?Q?2CNZsGiCVDbP+wlwuBn59MAT0VVSbav9o2rYmzxPK0NyuD3KhGbNUmeIZ2WX?= =?us-ascii?Q?MGbrKUMmYLdjRSchoIw/z53IL7Z/kvPtFljTxeCEI0Iq+n9ieC65dBFfUvW/?= =?us-ascii?Q?/rTVmN7SPZhJr00WQz8KKTL7udZzbIhy7XWmoPyYHgkBvrtprnQqT1rAYCdy?= =?us-ascii?Q?HopS50hB68yM1EEiCJf1k70RMZomDOYeoMFUaPqEzvTr5ToWUOzKevjYiAF+?= =?us-ascii?Q?cE7SlEDzmUZyIwJiS9T6Cv/n92bpiKPkAuNkseRNcqGbw6GPJ7OJDLTkzpDO?= =?us-ascii?Q?CJjNeUII0MKoDIKF2epV/vw5?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 051a8e84-71f8-498c-db16-08d9350bca31 X-MS-Exchange-CrossTenant-AuthSource: BL0PR12MB5506.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 21 Jun 2021 23:25:00.4047 (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: 16KkHj/6E9XbRThQx1Fy4F/jwiW2vnLSbWiKFQsmTqCBVol9XACQJx6VJ2dT4MzP X-MS-Exchange-Transport-CrossTenantHeadersStamped: BL1PR12MB5380 Precedence: bulk List-ID: X-Mailing-List: linux-rdma@vger.kernel.org On Fri, Jun 11, 2021 at 05:35:56PM +0800, Weihang Li wrote: > From: Jiaran Zhang > > During the reset, the driver calls dma_pool_destroy() to release the > dma_pool resources. If the dma_pool_free interface is called during the > modify_qp operation, an exception will occur. The completion > synchronization mechanism is used to ensure that dma_pool_destroy() is > executed after the dma_pool_free operation is complete. This should probably be a simple rwsem instead of faking one up with a refcount and completion. The only time you need this pattern is if the code is returning to userspace, which didn't look like was happening here. Jason