From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id D09F3EE4993 for ; Mon, 21 Aug 2023 07:18:17 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233599AbjHUHSR (ORCPT ); Mon, 21 Aug 2023 03:18:17 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:51000 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229949AbjHUHSQ (ORCPT ); Mon, 21 Aug 2023 03:18:16 -0400 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 16893A9 for ; Mon, 21 Aug 2023 00:17:31 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1692602250; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=ciBbLcY28Ot5+CnRRhBBgFJKp8dZk6YcG5T4tpJoW/E=; b=MrqZzvERemB9tRdcKeB+5i0Yk6LCW30Lwo0ys4SrsLLNpgHGW1e8V1qoJcADiNdBRb/00b ghJSDun52eTvcOrZEDrhJQApwW8UL+qsAZkW0RwZsieuI7Xwd7gmOQtlkmoKO4GKxOnYnW CYM96rCYRuKE9edeyu69NZ8LLHjo3mo= Received: from mimecast-mx02.redhat.com (mimecast-mx02.redhat.com [66.187.233.88]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-443-2yfPL0YeP9CJ9OjHrBd9mQ-1; Mon, 21 Aug 2023 03:17:26 -0400 X-MC-Unique: 2yfPL0YeP9CJ9OjHrBd9mQ-1 Received: from smtp.corp.redhat.com (int-mx07.intmail.prod.int.rdu2.redhat.com [10.11.54.7]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 6CBEE101A528; Mon, 21 Aug 2023 07:17:25 +0000 (UTC) Received: from localhost (dhcp-192-239.str.redhat.com [10.33.192.239]) by smtp.corp.redhat.com (Postfix) with ESMTPS id CE143140E919; Mon, 21 Aug 2023 07:17:24 +0000 (UTC) From: Cornelia Huck To: Marc Zyngier Cc: Jing Zhang , KVM , KVMARM , ARMLinux , Oliver Upton , Will Deacon , Paolo Bonzini , James Morse , Alexandru Elisei , Suzuki K Poulose , Fuad Tabba , Reiji Watanabe , Raghavendra Rao Ananta , Suraj Jitindar Singh Subject: Re: [PATCH v8 02/11] KVM: arm64: Document KVM_ARM_GET_REG_WRITABLE_MASKS In-Reply-To: <86sf8hg45k.wl-maz@kernel.org> Organization: "Red Hat GmbH, Sitz: Werner-von-Siemens-Ring 12, D-85630 Grasbrunn, Handelsregister: Amtsgericht =?utf-8?Q?M=C3=BCnchen=2C?= HRB 153243, =?utf-8?Q?Gesch=C3=A4ftsf=C3=BChrer=3A?= Ryan Barnhart, Charles Cachera, Michael O'Neill, Amy Ross" References: <20230807162210.2528230-1-jingzhangos@google.com> <20230807162210.2528230-3-jingzhangos@google.com> <878raex8g0.fsf@redhat.com> <874jkyqe13.fsf@redhat.com> <86sf8hg45k.wl-maz@kernel.org> User-Agent: Notmuch/0.37 (https://notmuchmail.org) Date: Mon, 21 Aug 2023 09:17:23 +0200 Message-ID: <87sf8c9858.fsf@redhat.com> MIME-Version: 1.0 Content-Type: text/plain X-Scanned-By: MIMEDefang 3.1 on 10.11.54.7 Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org On Thu, Aug 17 2023, Marc Zyngier wrote: > On Thu, 17 Aug 2023 09:16:56 +0100, > Cornelia Huck wrote: >> >> On Mon, Aug 14 2023, Jing Zhang wrote: >> >> > Maybe it'd be better to leave this to whenever we do need to add other >> > range support? >> >> My point is: How does userspace figure out if the kernel that is running >> supports ranges other than id regs? If this is just an insurance against >> changes that might arrive or not, we can live with the awkward "just try >> it out" approach; if we think it's likely that we'll need to extend it, >> we need to add the mechanism for userspace to find out about it now, or >> it would need to probe for presence of the mechanism... > > Agreed. Nothing like the present to address this sort of things. it > really doesn't cost much, and I'd rather have it right now. > > Here's a vague attempt at an advertising mechanism. If people are OK > with it, I can stash that on top of Jing's series. I think that looks reasonable.