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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?oV+5/+1J6z4zIXXZodsNvpfAhiHPTaNzwxb5nRa6HGKq1U53aZNKKGlq771I?= =?us-ascii?Q?n/rRrjC4AmpaiYQ2G6ObOtozmyGp26BCqK+933T+8lpYQWxvNTx3XYhL4L66?= =?us-ascii?Q?iiGRwpdYEw6ZksW9+80bOjRSoZeXvkI+SAJTc27sQQ49/HluxxXwHhfiWb5L?= =?us-ascii?Q?QzORY6toOoB37V7bmAVF5RKY5jLyzdVdfMWm/Wg4deHt7davQgfcoju7co3W?= =?us-ascii?Q?vIzmy2qbtxkuwvphXvVxYbqKQGGJV2l2+fZtTvPSb7+dMRqH7hSNYNMtuQdE?= =?us-ascii?Q?vmGtqcWY2AdrqZn+dGdXOfRXBA4PPRR3KLicwOxLCBCCYqsxFNQnOISrX699?= =?us-ascii?Q?Dif+OL0TodnYd/25hbgQCAT+PifVsy6x3LGtZV2OHgSzTN2csTdAGUGmrWWz?= =?us-ascii?Q?2ksBOGCwzDZrqB2+I6bbLDxFaH6Wv83VWYQuh62MRgmj0Ts4FUlk7035GBtE?= =?us-ascii?Q?Fos58d+cNMA/2Psh/yZ+/oAQOIKmC20YPN5TAdjeUl2wlCJKJlCvaj0Pm6dM?= =?us-ascii?Q?1QMEwRMNJRZKAMixSDdRbhMyQYjLqUzrVIIEZnO8e54UIi3pW32RFLPZlnKr?= =?us-ascii?Q?gAxuUgyorbH9grAqALZJ+YgeD5CqzVRN56joSjp6YKhBXFJ8bI62F+V+7Mx+?= =?us-ascii?Q?UM+xe4lWT2yDgI0ra+k/n2UsSLEARFF1Wmc6NKPA+2lFFxgR2O9QJO+TnTB5?= =?us-ascii?Q?YecTukx4S/HObbJO5IabiKow15kfx74XlnNoIGpk9rLB5CndLxkjt6INtLcY?= =?us-ascii?Q?L6wO54uTI0xnbaI6d33H9F0qQaCm3Q+cEqDmLCKqUnI/s+vFdhGXY9g2GRgH?= =?us-ascii?Q?93QjDu4XBAiDaRQ6ko+RYTvmChFqSmlZVxr6Fdxlm0ZC2YrOkzBrPwuWBFpe?= =?us-ascii?Q?fVaIK3Km1c/7Sf25QuaTnUxDC1t8iUKjAfhZ08Il+JcqAHoUBbVxkZ3O/0ba?= =?us-ascii?Q?Pv+PXNRSe1dM44yY/htLuc3AWiKUg+0di/rtmM9RW4JKdwX1c0MtEdz4RAkp?= =?us-ascii?Q?GMm1Qsi1tzCg4wkNgEq00OFWUOOnH//UtGitwrfQirz8XtrtflEqJaws6ZWs?= =?us-ascii?Q?en03efg1/X8MYHDV/fQwJmiuB2Fct7wPmSQu846syzrCPCZPAjJI4BjzAVu6?= =?us-ascii?Q?bjFEg5OSDg9tq80sWN6pSe4ZLsAvffGTs0XHZ22ZwmKSzAUrU9Ohhk80aAX0?= =?us-ascii?Q?OOkqpRRxJuBT52ijR61GTmaXEn3ClZvEYIOYAlD52ATJmPk/uPzRwebs7bQD?= =?us-ascii?Q?oSM9fWbwFBAmAHJSu/86AJerjrAsXl9Dsp9bjX18ScPEF8xF8GIAghnhgtCT?= =?us-ascii?Q?vmFv95OfLdVvIelwBxrD3NOg+gOtGMI1BchIh2D/W9So4gng0Hs5uuTD4OvF?= =?us-ascii?Q?VHWRsngxmQRw4RcwDxpegGTLWHDcEYvx/sGpdh/CKm/7UP+jOQHFKqeOpFVb?= =?us-ascii?Q?HDkquKeYumNehdxDjX6xrCPExddCjm8Sb4NXQeuzvaVU/t+4yW0OiIp99nYy?= =?us-ascii?Q?k0sdEQ6GDNOQ/Ar7Zpu74++dpPWzDDdokUMsrhMaZIchZFEeNXCHe4ob/tEb?= =?us-ascii?Q?6mAfP5mX7ziCy0US/artwTw+LvqOWrbDsSbzLhfL?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 117d074c-160e-42dc-2b7c-08db91f33d07 X-MS-Exchange-CrossTenant-AuthSource: LV2PR12MB5869.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 31 Jul 2023 18:23:29.1471 (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: RB31iQtGGsjAMlXZ1shh/+6lpftQ71TEioVhsyvQWloN/FnUDSY9KOyBfh5k9+ZC X-MS-Exchange-Transport-CrossTenantHeadersStamped: BL3PR12MB6450 Precedence: bulk List-ID: X-Mailing-List: linux-rdma@vger.kernel.org On Mon, Jul 31, 2023 at 01:20:35PM -0500, Bob Pearson wrote: > On 7/31/23 13:12, Jason Gunthorpe wrote: > > On Fri, Jul 21, 2023 at 03:50:17PM -0500, Bob Pearson wrote: > >> In cable pull testing some NICs can hold a send packet long enough > >> to allow ulp protocol stacks to destroy the qp and the cleanup > >> routines to timeout waiting for all qp references to be released. > >> When the NIC driver finally frees the SKB the qp pointer is no longer > >> valid and causes a seg fault in rxe_skb_tx_dtor(). > >> > >> This patch passes the qp index instead of the qp to the skb destructor > >> callback function. The call back is required to lookup the qp from the > >> index and if it has been destroyed the lookup will return NULL and the > >> qp will not be referenced avoiding the seg fault. > > > > And what if it is a different QP returned? > > > > Jason > > Since we are using xarray cyclic alloc you would have to create 16M QPs before the > index was reused. This is as good as it gets I think. Sounds terrible, why can't you store the QP pointer instead and hold a refcount on it? Jason