• Heiko Carstens's avatar
    [S390] smp: fix sigp sense handling · b3dcf3de
    Heiko Carstens authored
    
    
    sigp sense only returns the status of a cpu if it is non zero. If the
    status of the sensed cpu is all zeros condition code 0 (accpeted) is
    set and no status bits are returned.
    The current code however assumes that a status was returned and tests
    bits in it. This means uninitalized data is accessed with random
    results.
    Worst case is that the code that checks if cpu is offline on cpu
    hotplug assumes that the target cpu is offline while it is still
    running. This leads potentially to memory corruption since resources
    that are still needed by the target cpu will be freed and could be
    resused while still in use.
    Signed-off-by: default avatarHeiko Carstens <heiko.carstens@de.ibm.com>
    Signed-off-by: default avatarMartin Schwidefsky <schwidefsky@de.ibm.com>
    b3dcf3de