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IF DTE is fully zero, then all requests are blocked for that devid. > > It doesn't make sense that you'd pass over the DTEs after > probing if the original 0'd DTE was actually blocking? During boot, it sets certain default values includ dte.v. It doesn't clear everything. In probe path, if probe fails then its clearing it entirely. May be we should just remove ignore_device() completely? as - normal boot, its not yet configured, so no DMA is allowed - kdump boot, old DTE is still valid and let it continue? -Vasant