• S
    ktest: Add detection of triple faults · f1a5b962
    Steven Rostedt 提交于
    When a triple fault happens in a test, no call trace nor panic
    is displayed. Instead, the system reboots to the good kernel.
    Since the good kernel may display a boot prompt that matches the
    success string, ktest may think that the test succeeded, when it
    did not.
    
    Detecting triple faults is tricky because it is hard to generalize
    what a reboot looks like. The best that we can come up with for now
    is to examine the Linux banner. If we detect that the Linux banner
    matches the test we want to test, then look to see if we hit another
    Linux banner with a different kernel is booted. This can be assumed
    to be a triple fault.
    
    We can't just check for two Linux banners because things like
    early printk may cause the Linux banner to be displayed twice. Checking
    for different kernel versions should be the safe bet.
    
    If this for some reason detects a false triple boot. A new ktest
    config option is also created:
    
     DETECT_TRIPLE_FAULT
    
    This can be set to 0 to disable this checking.
    Signed-off-by: NSteven Rostedt <rostedt@goodmis.org>
    f1a5b962
ktest.pl 49.5 KB