• Dan Williams's avatar
    libnvdimm, namespace: fix label initialization to use valid seq numbers · b18d4b8a
    Dan Williams authored
    The set of valid sequence numbers is {1,2,3}. The specification
    indicates that an implementation should consider 0 a sign of a critical
    error:
    
        UEFI 2.7: 13.19 NVDIMM Label Protocol
    
        Software never writes the sequence number 00, so a correctly
        check-summed Index Block with this sequence number probably indicates a
        critical error. When software discovers this case it treats it as an
        invalid Index Block indication.
    
    While the expectation is that the invalid block is just thrown away, the
    Robustness Principle says we should fix this to make both sequence
    numbers valid.
    
    Fixes: f524bf27 ("libnvdimm: write pmem label set")
    Cc: <stable@vger.kernel.org>
    Reported-by: default avatarJuston Li <juston.li@intel.com>
    Signed-off-by: default avatarDan Williams <dan.j.williams@intel.com>
    b18d4b8a
label.c 31.2 KB