From: Joerg Roedel <jroedel@suse.de>
Date: Wed, 28 Jun 2017 10:52:48 +0000 (+0200)
Subject: iommu: Warn once when device_group callback returns NULL
X-Git-Tag: v4.13-rc1~52^2^9
X-Git-Url: https://git.kernel.dk/?a=commitdiff_plain;h=72dcac633475a5b331cf21f3525467d0e123395a;p=linux-2.6-block.git

iommu: Warn once when device_group callback returns NULL

This callback should never return NULL. Print a warning if
that happens so that we notice and can fix it.

Signed-off-by: Joerg Roedel <jroedel@suse.de>
---

diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c
index de09e1e35830..3f6ea160afed 100644
--- a/drivers/iommu/iommu.c
+++ b/drivers/iommu/iommu.c
@@ -1010,6 +1010,9 @@ struct iommu_group *iommu_group_get_for_dev(struct device *dev)
 	if (ops && ops->device_group)
 		group = ops->device_group(dev);
 
+	if (WARN_ON_ONCE(group == NULL))
+		return ERR_PTR(-EINVAL);
+
 	if (IS_ERR(group))
 		return group;