[PATCH AUTOSEL 5.4 42/78] iommu/virtio: Fix freeing of incomplete domains

[PATCH AUTOSEL 5.4 42/78] iommu/virtio: Fix freeing of incomplete domains

[Sasha Levin]

From: Jean-Philippe Brucker <jean-philippe-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org>

[ Upstream commit 7062af3ed2ba451029e3733d9f677c68f5ea9e77 ]

Calling viommu_domain_free() on a domain that hasn't been finalised (not
attached to any device, for example) can currently cause an Oops,
because we attempt to call ida_free() on ID 0, which may either be
unallocated or used by another domain.

Only initialise the vdomain->viommu pointer, which denotes a finalised
domain, at the end of a successful viommu_domain_finalise().

Fixes: edcd69ab9a32 ("iommu: Add virtio-iommu driver")
Reported-by: Eric Auger <eric.auger-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>
Signed-off-by: Jean-Philippe Brucker <jean-philippe-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org>
Reviewed-by: Robin Murphy <robin.murphy-5wv7dgnIgG8@public.gmane.org>
Link: https://lore.kernel.org/r/20200326093558.2641019-3-jean-philippe-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org
Signed-off-by: Joerg Roedel <jroedel-l3A5Bk7waGM@public.gmane.org>
Signed-off-by: Sasha Levin <sashal-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>
---
 drivers/iommu/virtio-iommu.c | 16 +++++++++-------
 1 file changed, 9 insertions(+), 7 deletions(-)

diff --git a/drivers/iommu/virtio-iommu.c b/drivers/iommu/virtio-iommu.c
index 3ea9d76829995..6c340a4f4fd28 100644
--- a/drivers/iommu/virtio-iommu.c
+++ b/drivers/iommu/virtio-iommu.c
@@ -614,18 +614,20 @@ static int viommu_domain_finalise(struct viommu_dev *viommu,
 	int ret;
 	struct viommu_domain *vdomain = to_viommu_domain(domain);
 
-	vdomain->viommu		= viommu;
-	vdomain->map_flags	= viommu->map_flags;
+	ret = ida_alloc_range(&viommu->domain_ids, viommu->first_domain,
+			      viommu->last_domain, GFP_KERNEL);
+	if (ret < 0)
+		return ret;
+
+	vdomain->id		= (unsigned int)ret;
 
 	domain->pgsize_bitmap	= viommu->pgsize_bitmap;
 	domain->geometry	= viommu->geometry;
 
-	ret = ida_alloc_range(&viommu->domain_ids, viommu->first_domain,
-			      viommu->last_domain, GFP_KERNEL);
-	if (ret >= 0)
-		vdomain->id = (unsigned int)ret;
+	vdomain->map_flags	= viommu->map_flags;
+	vdomain->viommu		= viommu;
 
-	return ret > 0 ? 0 : ret;
+	return 0;
 }
 
 static void viommu_domain_free(struct iommu_domain *domain)
-- 
2.20.1

[PATCH AUTOSEL 5.4 73/78] virtio-blk: improve virtqueue error to BLK_STS

[Sasha Levin]

From: Halil Pasic <pasic@linux.ibm.com>

[ Upstream commit 3d973b2e9a625996ee997c7303cd793b9d197c65 ]

Let's change the mapping between virtqueue_add errors to BLK_STS
statuses, so that -ENOSPC, which indicates virtqueue full is still
mapped to BLK_STS_DEV_RESOURCE, but -ENOMEM which indicates non-device
specific resource outage is mapped to BLK_STS_RESOURCE.

Signed-off-by: Halil Pasic <pasic@linux.ibm.com>
Link: https://lore.kernel.org/r/20200213123728.61216-3-pasic@linux.ibm.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/block/virtio_blk.c | 9 +++++++--
 1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/drivers/block/virtio_blk.c b/drivers/block/virtio_blk.c
index c2ed3e9128e3a..a55383b139df9 100644
--- a/drivers/block/virtio_blk.c
+++ b/drivers/block/virtio_blk.c
@@ -345,9 +345,14 @@ static blk_status_t virtio_queue_rq(struct blk_mq_hw_ctx *hctx,
 		if (err == -ENOSPC)
 			blk_mq_stop_hw_queue(hctx);
 		spin_unlock_irqrestore(&vblk->vqs[qid].lock, flags);
-		if (err == -ENOMEM || err == -ENOSPC)
+		switch (err) {
+		case -ENOSPC:
 			return BLK_STS_DEV_RESOURCE;
-		return BLK_STS_IOERR;
+		case -ENOMEM:
+			return BLK_STS_RESOURCE;
+		default:
+			return BLK_STS_IOERR;
+		}
 	}
 
 	if (bd->last && virtqueue_kick_prepare(vblk->vqs[qid].vq))
-- 
2.20.1