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Although rather than blocking them, maybe we just need to harden the mailbox path in CXL core so that when ~0s are read we return error and give up? and maybe a reset_prepare() to quiesce things. Just some random thoughts. > > DJ I agree that the PCI device lock does not serialize against the mailbox mutex, so a mailbox command could still be in progress during reset. Since cxl_reset also needs to work without cxl_pci bound, reset_prepare() and reset_done() seem like a good place to add this. I would prefer to do this as a follow-up along with hardening for ~0s read, if that is okay. I can send out a follow up RFC to discuss the specifics. -- Regards, Srirangan