[PATCH 5/6] s390: run user space and KVM guests with modified branch prediction

2018-02-06 Thread Martin Schwidefsky
Define TIF_ISOLATE_BP and TIF_ISOLATE_BP_GUEST and add the necessary plumbing in entry.S to be able to run user space and KVM guests with limited branch prediction. To switch a user space process to limited branch prediction the s390_isolate_bp() function has to be call, and to run a vCPU of a

[PATCH 5/6] s390: run user space and KVM guests with modified branch prediction

2018-02-06 Thread Martin Schwidefsky
Define TIF_ISOLATE_BP and TIF_ISOLATE_BP_GUEST and add the necessary plumbing in entry.S to be able to run user space and KVM guests with limited branch prediction. To switch a user space process to limited branch prediction the s390_isolate_bp() function has to be call, and to run a vCPU of a