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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?AsTylJOHVuG2TNga+3taD38X3925ZKBluG+i+xb1IoL1eI2ovcvGabcExbeZ?= =?us-ascii?Q?xnmSkpDA6BeXHgyFFxNDPPYJ2I4qmrPw05K+JV2BVU4Qp/rzG+5QV6eHkEwC?= =?us-ascii?Q?NrNj2r87OGnKT9nadFb8MLsONhb8cbmDCWQvQLV7xQENdpNtlo//uhGE+98u?= =?us-ascii?Q?Qyx1xQpn/n7crdhZYJbVeQu7YIwBdylwfaHnTqgMtDLqevAX9DDx9m26xXkE?= =?us-ascii?Q?uhwV6iQMshVMc7lhzmJb6Gva/qcaogH2hO61RwVdD9iMmzNSrFidmA+NX6bI?= =?us-ascii?Q?KAgwokqfUkCVacChoOyW9xKu/oai57qgJoM5DwYO74OekOdgmjGas4bKYrZ0?= =?us-ascii?Q?W+9mUYvnDKQOvJy474TATK4RoLQkxFL3fR951Sz9FORnMpMwpJ4TO88LvryI?= =?us-ascii?Q?Fd+drE3l7BWa4m9uPqqtVYcZAxgEGo3qxQpOQoHS5DTN8HEsTJHUnnUeTV5P?= =?us-ascii?Q?rK6UoZxzM45jPEP6BGX2EUvjtfRCqK3C7zz1bKS8sOF62keUx1UQ5NeZL5FP?= =?us-ascii?Q?LgUp2sCztTjCoiRecC4Bh5Wuezl5yNya63ZL731VQyx62pj/CCqJ8miO47Qm?= =?us-ascii?Q?I+6A4w7qAp9AgmD0DTIXNGJbvd3TbttyKBM1HAjZweophu2ETwhZy26vrKlm?= =?us-ascii?Q?r0PUZ9NJNL9BV7AUdAWuAtgG8688WBUJ53vMHa3Kg334iAlAB/EJPlG9C40c?= =?us-ascii?Q?2QtQGEERDSkz1NvBe/fhvrxE4Rn5ufJ87Bymsv5QOZS8xmL2SeVjNlzkFdqu?= =?us-ascii?Q?P3DaBjBcYhSF+zJzuJG5jdNxBRj/hH1IHZaUsd1KGiqioBXCZZNA1ev9TGR+?= =?us-ascii?Q?u2zazN6K8Mwz4I2Wjg2XNc2r+IJbk6eUxesyQTjxGMmuKcczLGahSlpD0feL?= =?us-ascii?Q?+oRTJbDIcgb2IkjORaZsHEdyxJYbRtGBQSZMIBlUh+G5ojkkYAcFgckz0hGU?= =?us-ascii?Q?IrLZvrgAUrMTpBGIdOUZVHrPQK/Zcms0aPrr2pbVCyP9YscYlbWZXx1REHo6?= =?us-ascii?Q?BiFj88MTncfwp2uSGjEA/0o97R+nwnQDRSVZOp7qBwld6Fgm5ORtHkg7zNTO?= =?us-ascii?Q?cpshQbpf5PkJ2USuBYmJsFChByb1CJgceu7eXOBlDSNbSPnPyPx1+0G/Nw5r?= =?us-ascii?Q?/Y2lagFi0ElM4XJDN3lmvp6aaN+Q/v20cWy1IkKzLwy/FQwGt/Rpu7EYD1Q5?= =?us-ascii?Q?AJQPlAsHfDYoDsskN1JgxS4l2IoSJyGJM2dOyGyPefudoalFJm9fmDjfmmYR?= =?us-ascii?Q?FC5diHPfsq+5cu7Ot59Q3e3VV+zCYC5YoDYcT/+TL2gJDHU94N+IGO5XWGS8?= =?us-ascii?Q?deHLdDMxDlvjQFS/UR7ePj2LUH+fHd0wZeey45Riyw73zye2hTpAZYFYb9FL?= =?us-ascii?Q?PbZJNxghMY1DMR+2j6Ii0hbjmLIIkYRaTF4wF4R0ksw/zHiXFUT2rg7RDatD?= =?us-ascii?Q?l46PH7S9c3rNeBXzl93GsnB8xWrf/ROBFRVRADddggmc7zKL6I4ETAqyK1Rj?= =?us-ascii?Q?RBdjvLkjyjDt0qHreQPR9wuDG9vAfpZ+ATpq9jFQXVHytBEEOFG3tJcHYInJ?= =?us-ascii?Q?Ec0yI5T850syELEUh5jHsI6a6l5OBOcvMyrFSLik?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 17b35a5f-76e3-4eab-fc30-08db2c729652 X-MS-Exchange-CrossTenant-AuthSource: LV2PR12MB5869.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 24 Mar 2023 14:18:06.5315 (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: 3gwkoNnSC7DxXfrhHVvdnKzQrmUj0apkXWb4Wqe2xZ5sFu31h9P3+N+pJkT++jdz X-MS-Exchange-Transport-CrossTenantHeadersStamped: SJ1PR12MB6171 Precedence: bulk List-ID: X-Mailing-List: linux-rdma@vger.kernel.org On Sat, Mar 04, 2023 at 11:45:28AM -0600, Bob Pearson wrote: > This patch adds a WARN_ON if the reference count of the object > passed to __rxe_put() is <= 0. This can only happen if there is a > bug in the rxe driver but has bad consequences if there is. > > Signed-off-by: Bob Pearson > --- > drivers/infiniband/sw/rxe/rxe_pool.c | 2 ++ > 1 file changed, 2 insertions(+) > > diff --git a/drivers/infiniband/sw/rxe/rxe_pool.c b/drivers/infiniband/sw/rxe/rxe_pool.c > index 3f6bd672cc2d..1b160e36b751 100644 > --- a/drivers/infiniband/sw/rxe/rxe_pool.c > +++ b/drivers/infiniband/sw/rxe/rxe_pool.c > @@ -244,6 +244,8 @@ int __rxe_get(struct rxe_pool_elem *elem) > > int __rxe_put(struct rxe_pool_elem *elem) > { > + if (WARN_ON(kref_read(&elem->ref_cnt) <= 0)) > + return 0; > return kref_put(&elem->ref_cnt, rxe_elem_release); refcount debugging in kref_put already does this kind of stuff, don't need to open code it. Jason