From mboxrd@z Thu Jan 1 00:00:00 1970 From: Paolo Bonzini Subject: Re: [PATCH 0/2] irqbypass/kvm: Silence registration errors Date: Wed, 11 May 2016 16:49:59 +0200 Message-ID: <57334697.4060408@redhat.com> References: <20160505174733.9576.61083.stgit@gimli.home> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Cc: feng.wu@intel.com, linux-kernel@vger.kernel.org, eric.auger@linaro.org To: Alex Williamson , kvm@vger.kernel.org Return-path: In-Reply-To: <20160505174733.9576.61083.stgit@gimli.home> Sender: linux-kernel-owner@vger.kernel.org List-Id: kvm.vger.kernel.org On 05/05/2016 19:58, Alex Williamson wrote: > Currently an AMD system using vfio-pci/kvm will issue a dev_info() for > every MSI/X vector registered because kvm_x86_ops does not support a > bypass mechanism except on Intel and the add_producer callback returns > an errno for that. This is meaningless, unintended, and confuses > users. We could simply have KVM's add_producer callback return 0 if > there's no bypass mechanism, but then why are we registering as an IRQ > bypass consumer in the first place? We also don't necessarily want to > simply remove the dev_info/pr_info on registration failure because > then we have no warning if something does actually go wrong. So > instead, let's conditionalize IRQ bypass registration on whether we > have any support for it, and to keep the de-registration path clean > and fill an unintended gap, let's ignore deregistration of NULL tokens > and prevent registration of the same. NULL isn't a good, unique > cookie anyway. Tested on AMD and non-PI Intel. Thanks, > > Alex Thanks, applying these patches to kvm/queue. Paolo