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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?3zubtLXjlKLjMAgFHpzhJ6URabiQlE8QxubaHvghELuN9FhkwALM3L4M2iuQ?= =?us-ascii?Q?FLNyD0KxECWFFrYelopHLpg6D+VfH8Cni4oruqzhzv6j7NJ1S/YMIjrTAKbP?= =?us-ascii?Q?xyjlyZY5rYqTv2Oqf/JBzI2WLTnN3W1k9wHh3+cWI+JG24MkznapaX8JmFmP?= =?us-ascii?Q?kUzGPd2vZzthcvrwR00n6X83Owi4YSkfpILY2VlMqg66YTSb+uAPehrL+raQ?= =?us-ascii?Q?fQJaaUI8frCD8RsmX9K7JtPgjn7RdqzfAX7AnesQ9mMH2LgM1xd36JTVsh2/?= =?us-ascii?Q?zQE2NSzeHLzkxY68QrGMc4OauWR4aIKAWtooPlfciDGrTiqdoi8IvrHQVcT9?= =?us-ascii?Q?2aF+Ar51fCWtbPaXE9LSMVWHPhJuVRQMJWf02I1fRi53A01oj/y6cF+bmnm/?= =?us-ascii?Q?V06rLOHN/xR3ksQb+dGMTeLQD79qE4sMz/meQ/rth1mLAGVyGp6819b+pieB?= =?us-ascii?Q?rN9Xg3vBnuEyHPir6PP0Nq4yLh/On+Z0A8SzubyFM81miYbCHL62yaIMih1H?= =?us-ascii?Q?TxnjJob36SQIS3d677GI9scHjNh1/yp7anWhkzPLUq82E+1qi5/IymT+JD83?= =?us-ascii?Q?obRtnGYBhbMBWxur/0mibeozUNY8ddhqYicyT7mxy8PUOQRCVznpbbXWAnBf?= =?us-ascii?Q?j+fb8o6Mz8qt7DTwyUgmLX/7GliM+iKA1pkvVoxLRb5AoktmRKgkbrkIYkzH?= =?us-ascii?Q?v9Mkb//Hm3nWHnEl2P7nWp4ggTlMFKbCT4J+qu2/FDqrhpnzV7Te2rLsG3bZ?= =?us-ascii?Q?8NHSkfzgmO1OjEf/xlZvd5kytGHo4n+vuKl7lPaqgY/zoYwPEWJwSe2FTQwb?= =?us-ascii?Q?MUVPO9n3jmPLZmeR6LuuhW5/2TxJ5PNptw68Fl8hrrY0c24leMuk5/n3URBz?= =?us-ascii?Q?MEXUf6jOVDW/RS+ljxsvC4fOD2qQQ4aM06VdbBMpEgiyypFZs+9oRQym51GM?= =?us-ascii?Q?sJyaYu5Fia4y/LGSCLoXBEouGQoik8gEYt7RwqIfFF4l+qsamgmyGfOnUohT?= =?us-ascii?Q?zZy3/XVmZX6GIsOkZw60VBt1mvgt4lPvk+C8OFiTM3BWBCf+y/GING7o2m5t?= =?us-ascii?Q?hitKAo8Vdi3NZYMXrUVL3y0hLBAglsko4ivdWqSO0slxjoTSrcNWe7w2K7dg?= =?us-ascii?Q?dpSJX0Iq6XH4uJ9m8ImkIOuiDFKHImcRUnHWdM/vtzEpfnp+pKsHMfJu/8Mr?= =?us-ascii?Q?C50DLeiXSlGAZXTelyZDj54yhT86IpToTgRh43h8GAn19nSJvUeAod4NiAPW?= =?us-ascii?Q?uXri9nguguEfsMwvDQwq84po9yYsQjvWS6vV1k3dVeTMfeUP1mOyQAsE/UOj?= =?us-ascii?Q?2B9ikpqcCDEkHUp6Sun1KHun?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: ba8461cb-e0ef-498a-ef6a-08d93bbde986 X-MS-Exchange-CrossTenant-AuthSource: BL0PR12MB5506.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 30 Jun 2021 11:55:10.3622 (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: NbRYe683+QvUr98LJYgPo/tbaRVD7iE4BobiSrEJZg4ENqBxSVDoAPfzqOTiSXPJ X-MS-Exchange-Transport-CrossTenantHeadersStamped: BL1PR12MB5238 Precedence: bulk List-ID: X-Mailing-List: linux-s390@vger.kernel.org On Tue, Jun 29, 2021 at 09:21:31AM -0400, Jason J. Herne wrote: > > + mutex_lock(&matrix_dev->lock); > > - if (matrix_mdev->kvm) { > > - matrix_mdev->kvm_busy = true; > > + if ((matrix_mdev->kvm) && (matrix_mdev->kvm->arch.crypto.crycbd)) { > > mutex_unlock(&matrix_dev->lock); > > > If this function cannot be entered concurrently on separate threads then I > think we can remove this mutex_unlock of matrix_dev->lock, Don't remove locking around data. If the data is written under a mutex it should be read under a mutex too. Jason