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>> + >> +     pci_cxl_hdm_init(pdev); > > I forgot to ask a question in v10, sorry about that. > > I am wondering why calling pci_cxl_hdm_init() in > cxl_pci_hdm_decoder_count_match() is needed. pci_bus_add_device() > already does pci_cxl_hdm_init(), so if my understanding is correct, > pdev->hdm is not NULL here, so this pci_cxl_hdm_init() here will not do > anything except checking if pdev->hdm is NULL. I am not sure if I miss > some cases for that. Hi Li Ming! Your question is valid. pci_bus_add_device() is the normal initialization path. The later call is a retry for cases where that attempt did not publish pdev->hdm, for example because allocation or MMIO mapping failed at that point. If initialization succeeded earlier, the existing cache is detected and the retry returns without rebuilding it. I clarified this behavior in the v12 commit message. -- Regards, Srirangan