>>> Of course, in practice we could reduce this to just one cpu_stl_data for >>> STFL and one or two cpu_stq_data for STFLE. >> >> I think STFLE can store more than two 64-bit words, can't it? > > Technically, yes. But there are less than 128 bits defined. Certainly much > less than the 4k bits that Michal prepares for. >
The architectural limit is 2k bytes (yes I said bytes). Check out "struct kvm_s390_vm_cpu_machine - fac_list" / KVM_S390_VM_CPU_MACHINE in arch/s390/include/uapi/asm/kvm.h. Here we prepared for that. Also note preparations for new stfl bits for future HW: cd1836f583d7 (KVM: s390: instruction-execution-protection support) -> bit 130 a679c547d19d (KVM: s390: gaccess: add ESOP2 handling) -> bit 131 However, for now 128 bit should be more then enough, as TCG still misses loads of features. CPU model still isn't properly wired up for TCG yet. -- Thanks, David
