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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?RBCX08kNFpZVZ0H3YllaG9cZlStpWxUWXxAeJEISg0NKGyAUacpT12eL+Qey?= =?us-ascii?Q?cP9ooXglp5VFv9uaPyQKZ66eM1wjd/7+sB/O+cCSgRIiCunSrm8G4h5hiVPX?= =?us-ascii?Q?KsJZ3rROa22k2enkPIh8g6uEiG0iyOG0QIF6krT9O+PoxT7R1o2di8EZwvqO?= =?us-ascii?Q?T3l2seKhUyExR5bHVlTd599vn+aJWAxb2hss9NFjWyvWxcL53OIrgRvqeOnE?= =?us-ascii?Q?omX8f8IZehq4OgXDIwe3W2D9hXGRKMTPAKYATZHJ8uyw9oNGCSd1YJoL41p2?= =?us-ascii?Q?R+2jEAryeZf75IoonUub+FGY8Lb53Dffvpk2PCZM3mo4/huHO6wRHMnR4T4L?= =?us-ascii?Q?invj36O7gWfkU+59sYoYLUHJDx09cmYdPWgd+5VpOfYm3JEXt5JVa+tClMwf?= =?us-ascii?Q?1ZS4bht8JcgkisZdUCLmdHT/oQYkN8TFEni7wDzbhdzspcyCqQXjRDBiTP8/?= =?us-ascii?Q?qhl3wFZ4LE+t+pLkBWvOnAxmBd+T2x+La+sADfEFNyItTHAe5l37Np69cC9s?= =?us-ascii?Q?68G2Yb4dEilLEYQj/mm3MZdHrbV6VkHd6bfnMa1/1N8TpM4MdvDb5CNkm5l7?= =?us-ascii?Q?Klb5bbqRMTcOPRDdzLEiP/Q2KmHW92LxGVrcxz+3AC2RBrmI66Y5Lz0U8afh?= =?us-ascii?Q?YU7+uEI9NkNa5Jad6KQ6arocze0LmMDRPb52L4NWTzyqT+3OZiHusTeIUsL4?= =?us-ascii?Q?QBgGW01SC7A+5gZGxaoGMySMvzVM0fKJLCGfk35HqrovVNGS95Rt1dc/Pgzy?= =?us-ascii?Q?cipZHR1QewllvleHyAXroem3yoqLBlk5YCniPXgjieAhNeUpm5SrmVFwwSJG?= =?us-ascii?Q?d9i5ZkuS2CHXM5MQxXm7jbo7UIhWdvFyUDiw9zrKOtInUdyUK7lCu9p9BCIO?= =?us-ascii?Q?TadZuFrjlo3Uh58w/ZrCzBvmzeEjkRBzlB0OiTWIkA6ULOPvPjTTqp3ekxVZ?= =?us-ascii?Q?V6anvyiaF6XasrL87ISXnKunlg8j5OZzii7MfMuAXeAbELlNywalk5y84cse?= =?us-ascii?Q?bEgxTktXwqHU9kzGeHk5+e2mBf1+aOuu8pfX6kuSAj/ImmMHmPYn2mUmrNYz?= =?us-ascii?Q?AFtIe0Y1P8Ogow32Jo0nOSM6Eja2V7XzenaN1Et1jkTvb6TYWX8Qfjf8l1EN?= =?us-ascii?Q?JauaX5CLHHIydEIsjcORumjjwiiSu79ng9XJ8r7qHJ3PSEEpiI4MFlNaWTSa?= =?us-ascii?Q?Kb9O1qV4f2C4p15kgcdCxjeaPUczX3wNqezs8poslYIpwA2+B0ifsTJSvtMt?= =?us-ascii?Q?LL/mUAPeoH4AmmHgtni+4A/Zge41dGQ3sNAEuo0BU8xWO5p9O7UqLl/Lux4h?= =?us-ascii?Q?IRrg4hzQPm+acApxJeNfxCnYIhNX9c7mrlOcYlE3AD/iln3rd4DeQmOfsMEC?= =?us-ascii?Q?aEnRbppepSSAliYdGvRsYOuXggJNgVnmNoQc6UWRAKb8lGu8PyrbG+GPR+HQ?= =?us-ascii?Q?z/jkxgFV/thNj4brDKSreZk6wg+aofMiJUYbzjzoskaxtY7F22wD4jaIpxFD?= =?us-ascii?Q?3Pw131He7EwqVFhiE78vmxpD1fxTzeRE9WtDs8GisDq5/hmujD1cLMoby/3t?= =?us-ascii?Q?jIqaqxE2jWqgHMUmI0YuczYpUIGSK1Syfk4D2oLL?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 5b2c1e2f-8ab3-4c10-4a39-08da6a496384 X-MS-Exchange-CrossTenant-AuthSource: MN2PR12MB4192.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 20 Jul 2022 12:14:26.2523 (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: QIbYYdwq10OecPbtZyFeKpAPzL3VUvXKKUxDwn/9frkt597jsIXesLyDvNtj5ZoA X-MS-Exchange-Transport-CrossTenantHeadersStamped: BN8PR12MB3220 Precedence: bulk List-ID: X-Mailing-List: linux-s390@vger.kernel.org On Tue, Jul 19, 2022 at 10:41:49PM -0400, Eric Farman wrote: > I suspect the second item (or something similar) is needed anyway, > because Alex' tree + this series crashes frequently in (usually) > mdev_remove. I haven't found an explanation for how we get in this > state, but admittedly didn't spent a lot of time on them since the > proposed changes to struct subchannel are a non-starter. It seems strange, at least from a mdev perspective, we shouldn't need an extra kref on the private. All references from the mdev universe, including via mdev_remove(), should halt after mdev_unregister_parent() returns, and ccw calls it in a context where the private must already be guarenteed valid. It suggests perhaps mdev_remove() is missing some references? Jason