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 7C7FDC4332F for ; Sun, 12 Dec 2021 20:55:37 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229525AbhLLUzg (ORCPT ); Sun, 12 Dec 2021 15:55:36 -0500 Received: from Galois.linutronix.de ([193.142.43.55]:59354 "EHLO galois.linutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229448AbhLLUzf (ORCPT ); Sun, 12 Dec 2021 15:55:35 -0500 From: Thomas Gleixner DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1639342533; 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=X/NAgpabmqU7SvS/VZzGUCF8aINHFotBjDodV/Kfsg4=; b=LpEiLakmAttHKGEe/3XvPR1wZM1Zx04nHfXTOtMTF+y2v8crOvCX0wLiHUiSxD2FMv70dd pVyrjpQGUNXm58MyJoCymnp+uSMpvxZnJPhGJa4bENiiTG4Tx6pYhvxGRFH0V84NDRbSzF 6essnvXYnG0FXAPt+wqOfhMKDE8tNgK0lOLemWVecVSYa/Isa8wFkTUp45sIKm8iuR7JRK 73Bi6yC8SORzL04D7o1qph0B/nQEXBpoCQTxZWY8AfMdKlWhBMJba8XHmqBLFYgd62OD6+ lCYxnrO3qvB6jMsSI4UwL+BfNgM4mUqSqh0zXXY8IN/6StMQhO6/wd+p+7HX6w== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1639342533; 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=X/NAgpabmqU7SvS/VZzGUCF8aINHFotBjDodV/Kfsg4=; b=bcZqTtGalDhuJSdfHxRVIoNBI2gdJizxqQQ5t6JV10dXy2tkk45yd0xK2H3YKD2oPO52mo TOV2vJAYg0Kr3gAQ== To: "Tian, Kevin" , Jason Gunthorpe Cc: "Jiang, Dave" , Logan Gunthorpe , LKML , Bjorn Helgaas , Marc Zygnier , Alex Williamson , "Dey, Megha" , "Raj, Ashok" , "linux-pci@vger.kernel.org" , Greg Kroah-Hartman , Jon Mason , Allen Hubbe , "linux-ntb@googlegroups.com" , "linux-s390@vger.kernel.org" , Heiko Carstens , Christian Borntraeger , "x86@kernel.org" , "Rodel, Jorg" , "iommu@lists.linux-foundation.org" Subject: RE: [patch 21/32] NTB/msi: Convert to msi_on_each_desc() In-Reply-To: References: <878rx480fk.ffs@tglx> <87sfv2yy19.ffs@tglx> <20211209162129.GS6385@nvidia.com> <878rwtzfh1.ffs@tglx> <20211209205835.GZ6385@nvidia.com> <8735n1zaz3.ffs@tglx> <87sfv1xq3b.ffs@tglx> <20211210123938.GF6385@nvidia.com> <87fsr0xp31.ffs@tglx> <875yrvwavf.ffs@tglx> Date: Sun, 12 Dec 2021 21:55:32 +0100 Message-ID: <87fsqxv8zf.ffs@tglx> MIME-Version: 1.0 Content-Type: text/plain Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Kevin, On Sun, Dec 12 2021 at 01:56, Kevin Tian wrote: >> From: Thomas Gleixner >> All I can find is drivers/iommu/virtio-iommu.c but I can't find anything >> vIR related there. > > Well, virtio-iommu is a para-virtualized vIOMMU implementations. > > In reality there are also fully emulated vIOMMU implementations (e.g. > Qemu fully emulates Intel/AMD/ARM IOMMUs). In those configurations > the IR logic in existing iommu drivers just apply: > > drivers/iommu/intel/irq_remapping.c > drivers/iommu/amd/iommu.c thanks for the explanation. So that's a full IOMMU emulation. I was more expecting a paravirtualized lightweight one. Thanks, tglx