From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mx1.redhat.com ([209.132.183.28]:60044 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725446AbfIMHnO (ORCPT ); Fri, 13 Sep 2019 03:43:14 -0400 Subject: Re: [PATCH] KVM: s390: Do not leak kernel stack data in the KVM_S390_INTERRUPT ioctl References: <20190912090050.20295-1-thuth@redhat.com> <6905df78-95f0-3d6d-aaae-910cd2d7a232@redhat.com> <253e67f6-0a41-13e8-4ca2-c651d5fcdb69@redhat.com> <239c8d0f-40fb-264a-bc10-445931a3cd9a@redhat.com> <20190913092030.373a9254.cohuck@redhat.com> <1d3f9799-41dd-4f7e-009b-c37610de22f7@redhat.com> From: Thomas Huth Message-ID: <5632e756-ee92-ad8a-8c7c-efc5ee011f52@redhat.com> Date: Fri, 13 Sep 2019 09:43:09 +0200 MIME-Version: 1.0 In-Reply-To: <1d3f9799-41dd-4f7e-009b-c37610de22f7@redhat.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-s390-owner@vger.kernel.org List-ID: To: David Hildenbrand , Cornelia Huck Cc: Christian Borntraeger , Janosch Frank , kvm@vger.kernel.org, linux-s390@vger.kernel.org, linux-kernel@vger.kernel.org On 13/09/2019 09.37, David Hildenbrand wrote: > On 13.09.19 09:34, Thomas Huth wrote: >> On 13/09/2019 09.20, Cornelia Huck wrote: >>> On Thu, 12 Sep 2019 13:23:38 +0200 >>> Thomas Huth wrote: >>> >>>> Hmm, we already talked about deprecating support for pre-3.15 kernel >>>> stuff in the past (see >>>> https://wiki.qemu.org/ChangeLog/2.12#Future_incompatible_changes for >>>> example), >>> >>> Btw: did we ever do that? I don't quite recall what code we were >>> talking about... >> >> We never really did - but we also never fixed the issue: If you run the >> current QEMU on a kernel before 3.15, it refuses to work due to the >> missing in-kernel FLIC device: >> >> Initialization of device s390-flic-kvm failed: KVM is missing capability >> KVM_CAP_DEVICE_CTR >> >> Since nobody really complained so far that running QEMU with KVM is >> still required on a kernel < 3.15, I think we could make this also >> "official" now and improve the error message a little bit, pointing the >> user to a kernel >= 3.15. > > Didn't we discuss back then to clean up *QEMU* and not the *kernel*? > Especially, to wait with cleanups until somebody requests to fix > instead. I mean you could have any user space in the wild that still > makes use of these interfaces ... Yes, that error message is part of QEMU, so I was referring to that one. Sorry for mixing this into a mail thread on the kernel mailing list :-/ Thomas