From 6b73044b2b0081ee3dd1cd6eaab7dee552601efb Mon Sep 17 00:00:00 2001 From: Martin Schwidefsky Date: Tue, 16 Jan 2018 07:36:46 +0100 Subject: s390: run user space and KVM guests with modified branch prediction 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 KVM guest associated with the current task with limited branch prediction call s390_isolate_bp_guest(). Signed-off-by: Martin Schwidefsky --- arch/s390/include/asm/processor.h | 3 +++ 1 file changed, 3 insertions(+) (limited to 'arch/s390/include/asm/processor.h') diff --git a/arch/s390/include/asm/processor.h b/arch/s390/include/asm/processor.h index 5f37f9ceef5e..7f2953c15c37 100644 --- a/arch/s390/include/asm/processor.h +++ b/arch/s390/include/asm/processor.h @@ -378,6 +378,9 @@ extern void memcpy_absolute(void *, void *, size_t); memcpy_absolute(&(dest), &__tmp, sizeof(__tmp)); \ } while (0) +extern int s390_isolate_bp(void); +extern int s390_isolate_bp_guest(void); + #endif /* __ASSEMBLY__ */ #endif /* __ASM_S390_PROCESSOR_H */ -- cgit v1.2.3