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X-OriginatorOrg: amd.com X-MS-Exchange-CrossTenant-OriginalArrivalTime: 22 Sep 2025 21:09:12.6654 (UTC) X-MS-Exchange-CrossTenant-Network-Message-Id: fb683005-d7c5-490a-f917-08ddfa1c47d1 X-MS-Exchange-CrossTenant-Id: 3dd8961f-e488-4e60-8e11-a82d994e183d X-MS-Exchange-CrossTenant-OriginalAttributedTenantConnectingIp: TenantId=3dd8961f-e488-4e60-8e11-a82d994e183d;Ip=[165.204.84.17];Helo=[satlexmb07.amd.com] X-MS-Exchange-CrossTenant-AuthSource: DS1PEPF00017098.namprd05.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Anonymous X-MS-Exchange-CrossTenant-FromEntityHeader: HybridOnPrem X-MS-Exchange-Transport-CrossTenantHeadersStamped: MW3PR12MB4442 [snip] > + > +/** > + * cxl_get_hpa_freespace - find a root decoder with free capacity per constraints > + * @endpoint: the endpoint requiring the HPA > + * @interleave_ways: number of entries in @host_bridges > + * @flags: CXL_DECODER_F flags for selecting RAM vs PMEM, and Type2 device > + * @max_avail_contig: output parameter of max contiguous bytes available in the > + * returned decoder > + * > + * Returns a pointer to a struct cxl_root_decoder > + * > + * The return tuple of a 'struct cxl_root_decoder' and 'bytes available given > + * in (@max_avail_contig))' is a point in time snapshot. If by the time the > + * caller goes to use this root decoder's capacity the capacity is reduced then s/capacity the/capacity and the Or you could cleanup to: "If by the time the caller goes to use this root decoder and its capacity is reduced then...". > + * caller needs to loop and retry. > + * > + * The returned root decoder has an elevated reference count that needs to be > + * put with cxl_put_root_decoder(cxlrd). > + */ > +struct cxl_root_decoder *cxl_get_hpa_freespace(struct cxl_memdev *cxlmd, > + int interleave_ways, > + unsigned long flags, > + resource_size_t *max_avail_contig) > +{ > + struct cxl_root *root __free(put_cxl_root) = NULL; > + struct cxl_port *endpoint = cxlmd->endpoint; > + struct cxlrd_max_context ctx = { > + .host_bridges = &endpoint->host_bridge, > + .flags = flags, > + }; > + struct cxl_port *root_port; > + > + if (!endpoint) { > + dev_dbg(&cxlmd->dev, "endpoint not linked to memdev\n"); > + return ERR_PTR(-ENXIO); > + } I'm 99% sure you'll crash in this case. The endpoint pointer is dereferenced when assigning to ctx above. > + > + root = find_cxl_root(endpoint); > + if (!root) { > + dev_dbg(&endpoint->dev, "endpoint can not be related to a root port\n"); s/can not/is not > + return ERR_PTR(-ENXIO); > + } > + > + root_port = &root->port; > + scoped_guard(rwsem_read, &cxl_rwsem.region) > + device_for_each_child(&root_port->dev, &ctx, find_max_hpa); Do you need the brackets for the scoped guard? I'm not sure how the macro expands when they aren't there.