On Wed, 5 May 2021, Melvin Vermeeren wrote: > Hi, > > On Wednesday, 5 May 2021 20:48:47 CEST Mikulas Patocka wrote: > > It doesn't matter if the device is discarded or not. If the metadata > > constains the discard filler, dm-integrity won't check the checksum - so > > the data can contain anything. > > > > ... > > > > The device after discard may contain random pattern (some SSDs really do) > > - so when the metadata contains the discard filler, the data may contain > > anything. > > So if an existing SSD is formatted with --no-wipe --data-device option and > then opened with --integrity-recalculate all metadata will contain the discard > filler with this patch. > > So then, all the current data in the drive is not checked for integrity > because it contains discard filler. This means that integrity recalculation > itself never takes place for existing data. Meaning that only newly written > data to SSD device will actually have integrity protection. > > Is this correct? Yes. Mikulas > Cheers, > > -- > Melvin Vermeeren > Systems engineer -- dm-devel mailing list dm-devel@xxxxxxxxxx https://listman.redhat.com/mailman/listinfo/dm-devel
