From mboxrd@z Thu Jan 1 00:00:00 1970 From: Alex Williamson Subject: [PATCH 2/3] vfio: Ignore sprurious notifies Date: Tue, 11 Jun 2013 10:01:48 -0600 Message-ID: <20130611160148.9995.96816.stgit@bling.home> References: <20130611155848.9995.41709.stgit@bling.home> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Cc: linux-kernel@vger.kernel.org, kvm@vger.kernel.org To: alex.williamson@redhat.com Return-path: In-Reply-To: <20130611155848.9995.41709.stgit@bling.home> Sender: linux-kernel-owner@vger.kernel.org List-Id: kvm.vger.kernel.org Remove debugging WARN_ON if we get a spurious notify for a group that no longer exists. No reports of anyone hitting this, but it would likely be a race and not a bug if they did. Signed-off-by: Alex Williamson --- drivers/vfio/vfio.c | 8 +++----- 1 file changed, 3 insertions(+), 5 deletions(-) diff --git a/drivers/vfio/vfio.c b/drivers/vfio/vfio.c index 1bed313..2edfecc 100644 --- a/drivers/vfio/vfio.c +++ b/drivers/vfio/vfio.c @@ -508,13 +508,11 @@ static int vfio_iommu_group_notifier(struct notifier_block *nb, struct device *dev = data; /* - * Need to go through a group_lock lookup to get a reference or - * we risk racing a group being removed. Leave a WARN_ON for - * debuging, but if the group no longer exists, a spurious notify - * is harmless. + * Need to go through a group_lock lookup to get a reference or we + * risk racing a group being removed. Ignore spurious notifies. */ group = vfio_group_try_get(group); - if (WARN_ON(!group)) + if (!group) return NOTIFY_OK; switch (action) {