3.13-stable review patch. If anyone has any objections, please let me know. ------------------ From: Dominik Dingel <dingel@xxxxxxxxxxxxxxxxxx> commit ff1f3cb4b3ac5d039f02679f34cb1498d110d241 upstream. The diagnose 500 subcode 3 contains the 32 bit subchannel id in bits 32-63 (counting from the left). As for other I/O instructions, bits 0-31 should be ignored and thus not be passed to kvm_io_bus_write_cookie(). This fixes a bug where the guest passed non-zero bits 0-31 which the host tried to interpret, leading to ioeventfd notification failures. Signed-off-by: Dominik Dingel <dingel@xxxxxxxxxxxxxxxxxx> Reviewed-by: Cornelia Huck <cornelia.huck@xxxxxxxxxx> Signed-off-by: Cornelia Huck <cornelia.huck@xxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- arch/s390/kvm/diag.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/arch/s390/kvm/diag.c +++ b/arch/s390/kvm/diag.c @@ -121,7 +121,7 @@ static int __diag_virtio_hypercall(struc * - gpr 4 contains the index on the bus (optionally) */ ret = kvm_io_bus_write_cookie(vcpu->kvm, KVM_VIRTIO_CCW_NOTIFY_BUS, - vcpu->run->s.regs.gprs[2], + vcpu->run->s.regs.gprs[2] & 0xffffffff, 8, &vcpu->run->s.regs.gprs[3], vcpu->run->s.regs.gprs[4]); -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html