Hi Gabe, I'm not sure about ARM, but for x86, when running with KVM the "magic instructions" use MMIO. Most of them work fine for x86, except readfile, which I need to post a patch for. I'm pretty sure that ARM works the same way, but maybe Andreas S. can answer better.
Cheers, Jason On Wed, Apr 19, 2017 at 6:09 PM Gabe Black <[email protected]> wrote: > Hi everybody. Weiping is a colleague of mine at Google, and he's trying to > use the m5 utility to take a checkpoint from within a simulation on aarch64 > which is running in KVM mode. The utility was causing an illegal > instruction fault, and so I started looking into it for him. > Unsurprisingly, the illegal instruction actually is an illegal instruction > which would trigger the checkpointing pseudo instruction if gem5 had seen > it, but I believe everything stayed within kvm land and so no checkpoint > was taken. > > I remember a while ago there being an effort to switch the pseudo > instructions over to be a magical device with the same behavior so that it > could trap reads/writes when in KVM mode. I see some evidence that support > was added for that in the 32 bit version of the m5 utility, but then later > removed because it caused other problems. I don't see any evidence that > that support was added to the 64 bit version. > > What's the current state of this? Is this something we could get working > with a reasonably small amount of effort, or is there a workaround, or...? > > Gabe > _______________________________________________ > gem5-dev mailing list > [email protected] > http://m5sim.org/mailman/listinfo/gem5-dev _______________________________________________ gem5-dev mailing list [email protected] http://m5sim.org/mailman/listinfo/gem5-dev
