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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?n4eFk72wLE3+AYWDE5uxqZFTx+c4ywGzl5DBALI+ZmKuN4Xwr60Z95Eqx98E?= =?us-ascii?Q?E/xIqPNiOaP2VdWtpsGe7VkHd/CDi74WnNY40i8XpLkfENUSTRv0Iou1qfbp?= =?us-ascii?Q?mIt2SSlT79qyyiLk8fPbPx+sqBooIwMUJnI74BXOob2oswklAxv4XPS5JXQ1?= =?us-ascii?Q?kqrxW1qbwQDaTt0Jj/f/NwkYXTzloz+90AXeotjJA6+tdLW6pZrszAKZ1yAu?= =?us-ascii?Q?81Zml470+flBuiiv4WW45hx7JEN28AJjx01whPCwl2JzcLvYva4inCEWGPFQ?= =?us-ascii?Q?rjDAortfc8kOEj7KNIau3b3owJskyP87lUxXX1xbtvoBqNjxxdhNcGtcyjuC?= =?us-ascii?Q?qjCpzdzp5/8GTGruzSDgKlIrhtD+GwowDVYpvY4xMwSWrX49bttyKnwUEtfI?= =?us-ascii?Q?wKzGAlcaFKh+q/L2XvZthhMXwLlIVZVOfbbBTBlzy1ac1sTKTWQhyrTOwqKC?= =?us-ascii?Q?2NlhUvsz66Xu7SU63ODjNR4kpMbEPnUcUxddu6H1C1ma4dqHonR6b7ZDMuqZ?= =?us-ascii?Q?ZQ5W6bdDFeF/5OkoSAwKZBwrw9wtXbrLfUMN6YcXirArk9z8zhDLXKaYWa4d?= =?us-ascii?Q?Da4BUciLapP5t36BSFI1Ugu6Y7jIE1p7V7PrxZWe7UDiI38z8hWnC21pSvLN?= =?us-ascii?Q?8pODBtuABCpKd4okrBzBEFR2M6WL4RMyOnNXmHLmTA7jbK2o4PLdFpeq3dwE?= =?us-ascii?Q?pv7PdxK8sIJVFD+6SteieKQgVfLnrXlHgWzzV4VvuGBY/iEACmyH4/D2mBBp?= =?us-ascii?Q?ZdVIVJHXWjxilWCcB1GiIn+V4NdhS0WRKeKrnTkOYwXmAVpKhTrP90Wd+AcU?= =?us-ascii?Q?g3JP7iKoUyqBUn+QREJ8f57JAWHK8QrCceve3MDB+p5HlXIozlq0ZykChIlB?= =?us-ascii?Q?kqrQn9nhNEJMbJcZMYf13NyV9xDey+g0yvS+GLVmSl/6x8fO1eywcXhe9bKc?= =?us-ascii?Q?s5+14M5wXFPIPrFVR6q9JhT5fcxkmshjdC/Ot0XmpfnBkXsHFO47yYeKgi05?= =?us-ascii?Q?03gGJeWl8RYjWJTTa/JSeuVWb2TM2LV3G/aBmV0Obop/N5hZ5Y0GPBYgoehy?= =?us-ascii?Q?K4/ADHyXELoC/POPmRLkKkDNK+Fb/X33lVizRbKquzktZI3NKAxEQJT6TO5q?= =?us-ascii?Q?fgPzOLMC6sMOPb6CXgF/W0sKal658YxQ1MnLGWV8FE9y0moH8vCkf3V85g+5?= =?us-ascii?Q?2WXVCWQx4lcWF1vTpTPiq83VpP2vz6/PxaYz4R9/M+sxchyCyhkAQ65JvZpo?= =?us-ascii?Q?Vx51d86IAwmwGFUx8C96DX/9NqbkM5PcTwfuxiCce5m7Q+PYVqZL50dx+Orq?= =?us-ascii?Q?fcuyqR2V9O9qGGYlkHLLA9rE?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 4ecbb1c0-5d42-4859-2e23-08d92cfb3693 X-MS-Exchange-CrossTenant-AuthSource: BL0PR12MB5506.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 11 Jun 2021 17:06:11.4948 (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: knrOoacp70SIvNdVII3uV3mxcpMfQ9icECGsOyWalMHb/mA4xk1pjIgAFiSo2xol X-MS-Exchange-Transport-CrossTenantHeadersStamped: BL1PR12MB5255 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Jun 09, 2021 at 06:46:34PM -0400, Tony Krowiak wrote: > The function pointer to the interception handler for the PQAP instruction > can get changed during the interception process. Let's add a > semaphore to struct kvm_s390_crypto to control read/write access to the > function pointer contained therein. > > The semaphore must be locked for write access by the vfio_ap device driver > when notified that the KVM pointer has been set or cleared. It must be > locked for read access by the interception framework when the PQAP > instruction is intercepted. > > Signed-off-by: Tony Krowiak > --- > arch/s390/include/asm/kvm_host.h | 6 +++--- > arch/s390/kvm/kvm-s390.c | 1 + > arch/s390/kvm/priv.c | 6 +++--- > drivers/s390/crypto/vfio_ap_ops.c | 14 ++++++++++---- > drivers/s390/crypto/vfio_ap_private.h | 2 +- > 5 files changed, 18 insertions(+), 11 deletions(-) This is alot better than the try_module_get! Reviewed-by: Jason Gunthorpe Jason