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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?ULGfgKRMjKN2Y/w99b/dOGPyYhGxTMgka2BDH3qdESQu3JA6UJXDdp098rqp?= =?us-ascii?Q?HBIkn9bfBEVDaI6+CtKsEPrrsvFVH+doIm3DKuXkALT6lraOC1S6QgN/Bkhc?= =?us-ascii?Q?YCe84QOlmdTUYaNJ5R0uEVx3j3qn+rWnGDwOCu2IbUM9+nEZEXvT6OrageAV?= =?us-ascii?Q?DxPKeiGyow1x1SKGqUlqaCcVap7mn20x+NUDTLWoWwDbUvvwERDXz9+dOB2w?= =?us-ascii?Q?9b3u1yPSwDkxraFcRqFItt1qnfQ/P+AjGTBNQAPf4oNFtzUp/SHkJfduYbuR?= =?us-ascii?Q?mpT2PWns9ds6QuBAo1RKoqUKFuHK2c3kEZzkx6M079sqXku0MeORggLd6tgT?= =?us-ascii?Q?JXR4DhTGY/hna6kAmcuBm7PhmLYimofQsl+HkmBMIrfw6x/fzhW8ygbZ8SSs?= =?us-ascii?Q?gpvjmexUpbWBSpzCBdglwhXv8T6ZUc94hx9e5Sw6FjAgdeCZMFnhcrlNRE92?= =?us-ascii?Q?kXYSjCvUVXq5bzp68iW4m63hSVmc2ZswHC55GxZUmLi3gcY+5ztSAECIv6Kc?= =?us-ascii?Q?gN3cNyFOT5Yx+wERXEPboZQLjlwnXSbDRvp7tNGXNbiFnCEk3WFOtH+q/v0E?= =?us-ascii?Q?2H23LuxkcxrNq4bHmf2t8/hXGW78W3511T1p0B4DK/ePyxtrITTLi4Laq5EN?= =?us-ascii?Q?p3gf44WFAiYe8YnX+nAXBmER11Jr+yBfB3DakCob+cUF/JRa9H8Xyth9njL6?= =?us-ascii?Q?1bnetWC0t7PfNCUsaDDahLLV3Vhfp3T/NS/xghFI0TMIDLJ2IDGMNKEVkTP/?= =?us-ascii?Q?uQZH8ove3tAm+av59kcXSJAcEZfJE1ZD3BQNnPnebkVOQXGB3RZmFYv2vC10?= =?us-ascii?Q?mCWTqNdNVAEfHahklOqEl80kVNn6bPDkiqxQnwogtz2nE0vlnwFtxt7//suD?= =?us-ascii?Q?/lme5Ni7/zoQrkoiTA3QPdPIRiVd7NfF61894WjfV5HBiyeb4XL2DKLJXTuk?= =?us-ascii?Q?J1CHBwAx5VsQoBM89vNzeLf7XDKc6Xs0k8WOijY8KXD7eJH+ILvWuEycr+IS?= =?us-ascii?Q?9KQbtI2qTtFlIsKf7gcArd3jfvYA78rgpDRUPld+jssC3UMRwknHgHL+jS90?= =?us-ascii?Q?NygbEF5gAYR3A3Qa+MpCvu5Icso1fGyHmbo8Ct1OjSLjvYm40dTBrQAVJkXZ?= =?us-ascii?Q?ky7Rzj562u/zMtPdkImK4Ta5mfnxTJmPmlqXaOq/hvEyASu96+A1DwR+XgoX?= =?us-ascii?Q?tlNfJU79ypwNZxUaa71p3A/nLNHGDunxZrhq/I9sxMS7UfFkxrnpH/YkBkNA?= =?us-ascii?Q?nXEN14boHgAVwAIbu0kGLGrtFeA7YfTrtppKVLitNqMmVmzWoGKooIFcjFHG?= =?us-ascii?Q?lvv2g0k2283ngz2OYYnO7+m/6NY0u8i3IEZlHGCuNy6i7a+LpMSiaRuqtkm2?= =?us-ascii?Q?TToD4I+ReDqfEyokrPVVZWFahHAtSnRzRTlaRyc31+H2TmK5E/PqjItOhry0?= =?us-ascii?Q?GjrcVZQtkVgutBQhRZHOtjv0cK5fRVNpAPgzTyfK7DFFHvx86VnbVyOfC01P?= =?us-ascii?Q?pW2CKCcqw9IbqtkZwB7QTX8Y7a1B/jofHlS/3oFo8AAlSD54JX6sDYzHG8bb?= =?us-ascii?Q?wiYxOGAagMTG9MtK4VPEYclNT3KEB86KL57ESHyu?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: f6e16875-38a5-4139-b877-08db92e29857 X-MS-Exchange-CrossTenant-AuthSource: LV2PR12MB5869.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 01 Aug 2023 22:56:52.1859 (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: /69ed12Mpnxy/EvdX8Yv9OnqQg1e7W7ipCBY/eKnfM9YywrI9u6lrOKkXqs5MJiJ X-MS-Exchange-Transport-CrossTenantHeadersStamped: BN9PR12MB5308 Precedence: bulk List-ID: X-Mailing-List: linux-rdma@vger.kernel.org On Mon, Jul 31, 2023 at 01:44:47PM -0500, Bob Pearson wrote: > On 7/31/23 13:32, Jason Gunthorpe wrote: > > On Mon, Jul 31, 2023 at 01:26:23PM -0500, Bob Pearson wrote: > >> On 7/31/23 13:17, Jason Gunthorpe wrote: > >>> On Fri, Jul 21, 2023 at 03:50:22PM -0500, Bob Pearson wrote: > >>>> Network interruptions may cause long delays in the processing of > >>>> send packets during which time the rxe driver may be unloaded. > >>>> This will cause seg faults when the packet is ultimately freed as > >>>> it calls the destructor function in the rxe driver. This has been > >>>> observed in cable pull fail over fail back testing. > >>> > >>> No, module reference counts are only for code that is touching > >>> function pointers. > >> > >> this is exactly the case here. it is the skb destructor function that > >> is carried by the skb. > > > > It can't possibly call it correctly without also having the rxe > > ib_device reference too though?? > > Nope. This was causing seg faults in testing when there was a long network > hang and the admin tried to reload the rxe driver. The skb code doesn't care > about the ib device at all. I don't get it, there aren't globals in rxe, so WTF is it doing if it isn't somehow tracing back to memory that is under the ib_device lifetime? Jason