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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?42BIP86yD8UwvgTu/L9Ckg85i+uvnceateKonsX+h0Dv3jR27x28nXf4PUog?= =?us-ascii?Q?sPemJX6HbwUmlfvUjm4ZvD5Q4PSjw89LkbS4tiQ4V1tt+OvmwMzkay3hbKqe?= =?us-ascii?Q?0P5PUitHir5M0ywylQwYz2prd5FOt2u47XMrVwbh6GOKwq8AjrUyv7UbnACN?= =?us-ascii?Q?Xdum/x2LDPWkXmFK65UiIbJPkrhoXxOOI85Tzdnw0oGntqayakipx3dUKXOl?= =?us-ascii?Q?4YGU0l67qNr/rhmNM6oMnFB1jFob7xdCMHzQKQ1+FDTrqXhrMdpYlLfgi05x?= =?us-ascii?Q?BZoYUW2SZ2fbwn0o5ORTdReT4NFmWMs44i1mAb5ZCvb97JDNpaS/BgZoxQc8?= =?us-ascii?Q?slGNbhfEpE0YhQXJggZ38/NKALGaU2S4WIciQ0+Dv85KMBf7q7nCE5A1iLIc?= =?us-ascii?Q?ns6dUM0Ltk8j8nNI/aFhGrSor7bvjmJXwVZZEom/3UcDijK1DwvJR5SBe/b/?= =?us-ascii?Q?vKAmHXrxdvnndasV8+0b2408+dNqI0jr7DiOUu+kc+CmQFZMgKVJHaNrCv0x?= =?us-ascii?Q?h1fxAIb3DYqeC6x9qQA45UKNzPcnktfHc2muDsXGCIoME6HaIgHMGUTzUUAO?= =?us-ascii?Q?jdJwpOCXAkuhrKIYmTE23OIlk6XBAgB3rOZaHRh7T8OgtJKN8qViYGCPMrtA?= =?us-ascii?Q?3SYxvekaKu6l2sDcmXHyVbb5QcU5vtqty8xIGm/PWg0nqAuIoq+zkOFiPO0o?= =?us-ascii?Q?m+Yw83PgSyxdR3x+mFTeGaPk57hAEXhFYdvVf9u1ZpvgU63DEdoIEoMmu2iy?= =?us-ascii?Q?tDPUEFhoRvuwANXCHOMZuX8yd9LRDQSXOLyWjf3uXPZ6qPXm5QG75MfOuuNF?= =?us-ascii?Q?QgFphEcZFDmLII/cCU6ATeWOUs6QU5n0Bs2l/4FiJQiuKikD0jsIl8X9iU9p?= =?us-ascii?Q?PRZFnLHaBdrL/r/G6K17AEmtll/CDTD0QSy2oS0uRU7Ic4rtBDyl+Lni++3r?= =?us-ascii?Q?YZL8v0WxV3/pj6SvvHZKTIngDLkHgkby/vW6uJGYb+kvEC/ppLceKTYIRcDx?= =?us-ascii?Q?obJFn1dffhdswevd1NJiul8e4okZmLpCnhcaU/JyPLPKP0WbforAFleUiqYY?= =?us-ascii?Q?uL/qBfteUDM/GHvDFPW6ny3281zAa/RA+jvzMeNyd0sInFJAcuwPLtW5OszF?= =?us-ascii?Q?6foJ3DJeD9fTX+Ky8+/5JzaBi1FXa2Cq0ExT3YHDR8d/wIvfTrjdoEJypbGp?= =?us-ascii?Q?Jl6cIEQ6Mzbsa8v/xvcJtyXIlkxx6C3CgGGSJEfiFLP+cOMRdNbxPJZ1ds6V?= =?us-ascii?Q?/5h5M5aEQfGP+RZYCBNBcb2qneJCek7Dvu3ZrqJa+2f7jjwDhVfo6KuxDXWS?= =?us-ascii?Q?Yw6XzWKQg1GRIxFaZ2tU6tsReuw1FvLbol2vlWWZP7GtxwIyLt8KW4aNIlSD?= =?us-ascii?Q?/EBj6NBzwH0XIaCluUgyFh2DnlvKxHcH00RM2RUuzg/Q86T/oOO8yK0fG/5f?= =?us-ascii?Q?tbUql3y/WFkxvshF9VcuuEB3i3RralMCkuRwe2FTKoZBG1kFpe1czPEHltqU?= =?us-ascii?Q?4o2MVDAcdfqO8wKqo+gmWBhGdq1xpLAMWLq97NBglLBvX3dSriH8yWuUzA42?= =?us-ascii?Q?RVfhoPB5OozD+/pVi98iztfZGdnuUHwNFFvAc1D8?= X-MS-Exchange-CrossTenant-Network-Message-Id: d1d58f7c-3094-4b57-093b-08dbc87eab4c X-MS-Exchange-CrossTenant-AuthSource: SA1PR11MB6733.namprd11.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 09 Oct 2023 04:17:36.9649 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: 46c98d88-e344-4ed4-8496-4ed7712e255d X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: 89PDWbW/IV7TEJk4gQc2odDieVJghk38FFKwj4o00NshZ/YX5bRI62fhMbeG/QJ6FavmPlLWf07bTShxOCxXXA== X-MS-Exchange-Transport-CrossTenantHeadersStamped: PH8PR11MB7968 X-OriginatorOrg: intel.com X-Spam-Status: No, score=-4.4 required=5.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,RCVD_IN_DNSWL_MED, SPF_HELO_NONE,SPF_NONE autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net Dan Williams wrote: > The sanitize operation is destructive and the expectation is that the > device is unmapped while in progress. The current implementation does a > lockless check for decoders being active, but then does nothing to > prevent decoders from racing to be committed. Introduce state tracking > to resolve this race. > > This incidentally cleans up unpriveleged userspace from triggering mmio > read cycles by spinning on reading the 'securiry/state' attribute. Which > at a minimum is a waste since the kernel state machine can cache the > completion result. > > Lastly cxl_mem_sanitize() was mistakenly marked EXPORT_SYMBOL() in the > original implementation, but an export was never required. > > Fixes: 0c36b6ad436a ("cxl/mbox: Add sanitization handling machinery") > Cc: Davidlohr Bueso > Signed-off-by: Dan Williams > --- [snip] > --- a/drivers/cxl/core/hdm.c > +++ b/drivers/cxl/core/hdm.c > @@ -650,6 +650,25 @@ static int cxl_decoder_commit(struct cxl_decoder *cxld) > return -EBUSY; > } > > + /* > + * For endpoint decoders hosted on CXL memory devices that > + * support the sanitize operation, make sure sanitize is not in-flight. > + */ > + if (is_endpoint_decoder(&cxld->dev)) { > + struct cxl_endpoint_decoder *cxled = > + to_cxl_endpoint_decoder(&cxld->dev); > + struct cxl_memdev *cxlmd = cxled_to_memdev(cxled); > + struct cxl_memdev_state *mds = > + to_cxl_memdev_state(cxlmd->cxlds); > + > + if (mds && mds->security.sanitize_active) { I'm curious why this check does not need to hold the mds->mbox_mutex? Or how this may be protected by the cxl_dpa_rwsem? Ira [snip]