On 6 July 2018 at 11:11, Alex Bennée <alex.bennee@xxxxxxxxxx> wrote: > > Peter Maydell <peter.maydell@xxxxxxxxxx> writes: > >> On 6 July 2018 at 10:20, Alex Bennée <alex.bennee@xxxxxxxxxx> wrote: >>> For the most part in QEMU with KVM we just treat the list of registers >>> we get from the OS as an opaque blob of things we save to memory and >>> pass back. >> >> This is specifically not the case for the SVE registers -- we >> will need extra code to handle them. (The current code only >> allows for the possibility of 64-bit registers, so if we'd >> allowed the kernel to hand it the larger SVE registers it would >> just have fallen over. This is why QEMU needs to specifically >> enable SVE via the VCPU_INIT call.) > > Ahh right. So currently both the KVM_GET_REG_LIST and the core registers > use KVM_GET/SET_ONE_REG which certainly won't do the trick. So I guess > we need another IOCTL (or to enhance the current one) and a KVM > capability bit as well? It is still GET/SET_ONE_REG, but the size of the register (which is encoded in its ID number) is not something the current code will cope with (see the switches on regidx & KVM_REG_SIZE_MASK in write_kvmstate_to_list() and write_list_to_kvmstate()). thanks -- PMM _______________________________________________ kvmarm mailing list kvmarm@xxxxxxxxxxxxxxxxxxxxx https://lists.cs.columbia.edu/mailman/listinfo/kvmarm
