4.19-stable review patch. If anyone has any objections, please let me know. ------------------ From: Diana Craciun <diana.craciun@xxxxxxx> commit e7aa61f47b23afbec41031bc47ca8d6cb6516abc upstream. Switching from the guest to host is another place where the speculative accesses can be exploited. Flush the branch predictor when entering KVM. Signed-off-by: Diana Craciun <diana.craciun@xxxxxxx> Signed-off-by: Michael Ellerman <mpe@xxxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- arch/powerpc/kvm/bookehv_interrupts.S | 4 ++++ 1 file changed, 4 insertions(+) --- a/arch/powerpc/kvm/bookehv_interrupts.S +++ b/arch/powerpc/kvm/bookehv_interrupts.S @@ -75,6 +75,10 @@ PPC_LL r1, VCPU_HOST_STACK(r4) PPC_LL r2, HOST_R2(r1) +START_BTB_FLUSH_SECTION + BTB_FLUSH(r10) +END_BTB_FLUSH_SECTION + mfspr r10, SPRN_PID lwz r8, VCPU_HOST_PID(r4) PPC_LL r11, VCPU_SHARED(r4)
