title: Loading the FS mode with multi-core O3CPU in gem5
body: <p>I need to run fs mode with 64 O3 cores.</p>
  <p>According to：
  <a href="https://stackoverflow.com/questions/50248067/how-to-run-a-gem5-arm-aarch64-full-system-simulation-with-fs-py-with-more-than-8">How to run a gem5 arm aarch64 full system simulation with fs.py with more than 8 cores?</a>
  I should use one of these two methods：<strong>GICv2 extensions</strong> or <strong>GICv3</strong>.</p>
  <p>But when I add the command：</p>
  <p><code>--param 'system.realview.gic.gem5_extensions = True</code>,</p>
  <p>the terminal continues to output information similar to the following:</p>
  <p><code>Warn:context 2:1900000 consecutive store conditional failures</code>.</p>
  <p>When I add the command：</p>
  <p><code>--machine-type VExpress_GEM5_V2</code>,</p>
  <p>the terminal outputs the following information:</p>
  <p><code>warn: Gicv3Distributor::write(): setting ARE to 0 is not supported!</code>,
  and there is no more information after that, it seems to be still running.</p>
  <p>I read this mailing list:
  <a href="https://www.mail-archive.com/gem5-users@gem5.org/msg18133.html" rel="nofollow noreferrer">https://www.mail-archive.com/gem5-users@gem5.org/msg18133.html</a>
  It seems that the multi-O3CPU is not used to boot the Linux system in the end.</p>
  <p>Therefore, should I use AtomicSimpleCPU to boot, establish a checkpoint and then load the checkpoint with  out-of-order cores? Does the boot configuration need to be similar to the runtime configuration?</p>