From: David Hildenbrand Date: Tue, 8 Mar 2016 11:24:30 +0000 (+0100) Subject: KVM: s390: correct fprs on SIGP (STOP AND) STORE STATUS X-Git-Tag: v4.5~14^2~3 X-Git-Url: https://asedeno.scripts.mit.edu/gitweb/?a=commitdiff_plain;h=9522b37f5a8c7bfabe46eecadf2e130f1103f337;p=linux.git KVM: s390: correct fprs on SIGP (STOP AND) STORE STATUS With MACHINE_HAS_VX, we convert the floating point registers from the vector registeres when storing the status. For other VCPUs, these are stored to vcpu->run->s.regs.vrs, but we are using current->thread.fpu.vxrs, which resolves to the currently loaded VCPU. So kvm_s390_store_status_unloaded() currently writes the wrong floating point registers (converted from the vector registers) when called from another VCPU on a z13. This is only the case for old user space not handling SIGP STORE STATUS and SIGP STOP AND STORE STATUS, but relying on the kernel implementation. All other calls come from the loaded VCPU via kvm_s390_store_status(). Fixes: 9abc2a08a7d6 (KVM: s390: fix memory overwrites when vx is disabled) Reviewed-by: Christian Borntraeger Cc: stable@vger.kernel.org # v4.4+ Signed-off-by: David Hildenbrand Signed-off-by: Christian Borntraeger Signed-off-by: Paolo Bonzini --- diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c index 4af21c771f9b..03dfe9c667f4 100644 --- a/arch/s390/kvm/kvm-s390.c +++ b/arch/s390/kvm/kvm-s390.c @@ -2381,7 +2381,7 @@ int kvm_s390_store_status_unloaded(struct kvm_vcpu *vcpu, unsigned long gpa) /* manually convert vector registers if necessary */ if (MACHINE_HAS_VX) { - convert_vx_to_fp(fprs, current->thread.fpu.vxrs); + convert_vx_to_fp(fprs, (__vector128 *) vcpu->run->s.regs.vrs); rc = write_guest_abs(vcpu, gpa + __LC_FPREGS_SAVE_AREA, fprs, 128); } else {