On 04/15/2013 11:52 AM, Alexander Spyridakis wrote: > On 15 April 2013 11:39, Andre Przywara <andre.przywara@xxxxxxxxxx > <mailto:andre.przywara@xxxxxxxxxx>> wrote: > > > [Q: does > > all the hyp mode code have to also run on the A15s or > > is it A7-safe?] > > Good point. It seems like the code hangs in init_hyp_mode(). > Will do more debugging in there now. > > > I've run on this problem before, while trying to run KVM guests on A7 cores. > > For some reason the 3rd A7 hangs in arch/arm/kvm/init.S, on the > instruction that updates HSCTLR between the two isbs on __do_hyp_init > (mcr p15, 4, r0, c1, c0, 0). If you boot the system with maxcpus=4 then > init_hyp_mode() will not hang on the A7 cluster. Other than that from my > limited testing KVM on A7 works on a usual linux guest. I also tried to > only boot the 3rd A7 core to rule out any racing issues, but still the > same behaviour applies. Could well be the same issue here. I chased it down till CPU 2 goes into HYP mode to do the initialization. I am running with maxcpus=3 (this increases the likelyhood that kvm_target_cpu() runs on an A15), so CPU #2 is the only one A7. As the HYP mode exception table is empty except for the HVC trap, it may be looping here. I am trying now to get the PC of the faulty instruction. (on a TC2: 0-1: A15, 2-4: A7) kvm_target_cpu() on CPU #1, part is c0f0 kvm [1]: entering init_hyp_mode on CPU 1 kvm [1]: kvm_mmu_init() returned 0 on CPU 1 kvm [1]: hyp_get_vectors() finished on CPU 1 kvm [1]: allocated stack for HV mode on 5 CPUs, now on CPU 1 kvm [0]: entering cpu_init_hyp_mode(8050fde0) on CPU 0 kvm [0]: c_i_h_m: set vectors finished kvm [0]: c_i_h_m: initialization of local variables finished kvm [0]: c_i_h_m: kvm_call_hyp() finished, returning... kvm [1]: entering cpu_init_hyp_mode(8050fde0) on CPU 1 kvm [1]: c_i_h_m: set vectors finished kvm [1]: c_i_h_m: initialization of local variables finished kvm [1]: c_i_h_m: kvm_call_hyp() finished, returning... kvm [0]: entering cpu_init_hyp_mode(8050fde0) on CPU 2 kvm [0]: c_i_h_m: set vectors finished kvm [0]: c_i_h_m: initialization of local variables finished Regards, Andre. _______________________________________________ kvmarm mailing list kvmarm@xxxxxxxxxxxxxxxxxxxxx https://lists.cs.columbia.edu/cucslists/listinfo/kvmarm
