• Damien Le Moal's avatar
    scsi: core: save/restore command resid for error handling · 8f8fed0c
    Damien Le Moal authored
    When a non-passthrough command is terminated with CHECK CONDITION, request
    sense is executed by hijacking the command descriptor. Since
    scsi_eh_prep_cmnd() and scsi_eh_restore_cmnd() do not save/restore the
    original command resid, the value returned on failure of the original
    command is lost and replaced with the value set by the execution of the
    request sense command. This value may in many instances be unaligned to the
    device sector size, causing sd_done() to print a warning message about the
    incorrect unaligned resid before the command is retried.
    
    Fix this problem by saving the original command residual in struct
    scsi_eh_save using scsi_eh_prep_cmnd() and restoring it in
    scsi_eh_restore_cmnd(). In addition, to make sure that the request sense
    command is executed with a correctly initialized command structure, also
    reset the residual to 0 in scsi_eh_prep_cmnd() after saving the original
    command value in struct scsi_eh_save.
    
    Cc: stable@vger.kernel.org
    Link: https://lore.kernel.org/r/20191001074839.1994-1-damien.lemoal@wdc.comSigned-off-by: default avatarDamien Le Moal <damien.lemoal@wdc.com>
    Reviewed-by: default avatarBart Van Assche <bvanassche@acm.org>
    Signed-off-by: default avatarMartin K. Petersen <martin.petersen@oracle.com>
    8f8fed0c
scsi_error.c 68.2 KB