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 X-Spam-Level: X-Spam-Status: No, score=-8.3 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_PASS,URIBL_BLOCKED,USER_AGENT_MUTT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 2CEA7C282C3 for ; Tue, 22 Jan 2019 05:50:00 +0000 (UTC) Received: from lists.ozlabs.org (lists.ozlabs.org [203.11.71.2]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 9A8D820879 for ; Tue, 22 Jan 2019 05:49:59 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=ozlabs.org header.i=@ozlabs.org header.b="uKcJblXa" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 9A8D820879 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=ozlabs.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Received: from lists.ozlabs.org (lists.ozlabs.org [IPv6:2401:3900:2:1::3]) by lists.ozlabs.org (Postfix) with ESMTP id 43kHYx1lbfzDqMn for ; Tue, 22 Jan 2019 16:49:57 +1100 (AEDT) Received: from ozlabs.org (bilbo.ozlabs.org [IPv6:2401:3900:2:1::2]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 43kHPt0yp8zDqMv for ; Tue, 22 Jan 2019 16:42:58 +1100 (AEDT) Authentication-Results: lists.ozlabs.org; dmarc=none (p=none dis=none) header.from=ozlabs.org Authentication-Results: lists.ozlabs.org; dkim=pass (2048-bit key; secure) header.d=ozlabs.org header.i=@ozlabs.org header.b="uKcJblXa"; dkim-atps=neutral Received: by ozlabs.org (Postfix, from userid 1003) id 43kHPs58Gkz9sBQ; Tue, 22 Jan 2019 16:42:57 +1100 (AEDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=ozlabs.org; s=201707; t=1548135777; bh=qPXiFSvEqaA7ZqF25fMj+UZctDexxwToJ2hO+G9lINU=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=uKcJblXaYZR4EVtZbgDKRVOaMa55p5S0M/6YqvqwNLh4Q1xaRLT1cpzQ/z/JS6LKY W/sD5uNLYRSI914JOiXqMqma/pqpnBZeCeP3R2ACE367XeyX+tu9IJDsiKZ+Qm+YKI /jhh+k96WmzuG6dYJxYW/iAiScaXqgPygc64Np8V22RPRfS78F59IThkrka2sdreMs qlVxL43f/SFuw7EbUZwIbXPArwr4Id3jHICKUN1oFysjLz9tG/yhurJHPRshTJBwAx 6fAB2yvy4cguSRRgysO24KW3dKkvWOazNX3FMMbgZP+cA3+xuDEWGP5H/NPKQlccuz /VilHrQhKpSfQ== Date: Tue, 22 Jan 2019 16:09:52 +1100 From: Paul Mackerras To: =?iso-8859-1?Q?C=E9dric?= Le Goater Subject: Re: [PATCH 06/19] KVM: PPC: Book3S HV: add a GET_ESB_FD control to the XIVE native device Message-ID: <20190122050952.GD15124@blackberry> References: <20190107184331.8429-1-clg@kaod.org> <20190107184331.8429-7-clg@kaod.org> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <20190107184331.8429-7-clg@kaod.org> User-Agent: Mutt/1.5.24 (2015-08-30) X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: kvm@vger.kernel.org, kvm-ppc@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, David Gibson Errors-To: linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Sender: "Linuxppc-dev" On Mon, Jan 07, 2019 at 07:43:18PM +0100, Cédric Le Goater wrote: > This will let the guest create a memory mapping to expose the ESB MMIO > regions used to control the interrupt sources, to trigger events, to > EOI or to turn off the sources. > > Signed-off-by: Cédric Le Goater > --- > arch/powerpc/include/uapi/asm/kvm.h | 4 ++ > arch/powerpc/kvm/book3s_xive_native.c | 97 +++++++++++++++++++++++++++ > 2 files changed, 101 insertions(+) > > diff --git a/arch/powerpc/include/uapi/asm/kvm.h b/arch/powerpc/include/uapi/asm/kvm.h > index 8c876c166ef2..6bb61ba141c2 100644 > --- a/arch/powerpc/include/uapi/asm/kvm.h > +++ b/arch/powerpc/include/uapi/asm/kvm.h > @@ -675,4 +675,8 @@ struct kvm_ppc_cpu_char { > #define KVM_XICS_PRESENTED (1ULL << 43) > #define KVM_XICS_QUEUED (1ULL << 44) > > +/* POWER9 XIVE Native Interrupt Controller */ > +#define KVM_DEV_XIVE_GRP_CTRL 1 > +#define KVM_DEV_XIVE_GET_ESB_FD 1 > + > #endif /* __LINUX_KVM_POWERPC_H */ > diff --git a/arch/powerpc/kvm/book3s_xive_native.c b/arch/powerpc/kvm/book3s_xive_native.c > index 115143e76c45..e20081f0c8d4 100644 > --- a/arch/powerpc/kvm/book3s_xive_native.c > +++ b/arch/powerpc/kvm/book3s_xive_native.c > @@ -153,6 +153,85 @@ int kvmppc_xive_native_connect_vcpu(struct kvm_device *dev, > return rc; > } > > +static int xive_native_esb_fault(struct vm_fault *vmf) > +{ > + struct vm_area_struct *vma = vmf->vma; > + struct kvmppc_xive *xive = vma->vm_file->private_data; > + struct kvmppc_xive_src_block *sb; > + struct kvmppc_xive_irq_state *state; > + struct xive_irq_data *xd; > + u32 hw_num; > + u16 src; > + u64 page; > + unsigned long irq; > + > + /* > + * Linux/KVM uses a two pages ESB setting, one for trigger and > + * one for EOI > + */ > + irq = vmf->pgoff / 2; > + > + sb = kvmppc_xive_find_source(xive, irq, &src); > + if (!sb) { > + pr_err("%s: source %lx not found !\n", __func__, irq); In general it's a bad idea to have a printk that userspace can trigger at will without any rate-limiting. Is there a real reason why this printk is needed (and can't be pr_devel)? > + return VM_FAULT_SIGBUS; > + } > + > + state = &sb->irq_state[src]; > + kvmppc_xive_select_irq(state, &hw_num, &xd); > + > + arch_spin_lock(&sb->lock); > + > + /* > + * first/even page is for trigger > + * second/odd page is for EOI and management. > + */ > + page = vmf->pgoff % 2 ? xd->eoi_page : xd->trig_page; > + arch_spin_unlock(&sb->lock); > + > + if (!page) { > + pr_err("%s: acessing invalid ESB page for source %lx !\n", > + __func__, irq); Does this represent a exceptional condition that userspace can't just trigger at will (i.e. it implies the presence of a kernel bug)? If not then the same comment as above applies. Paul.