From: Pierre Morel <pmorel@linux.ibm.com>
To: linux-kernel@vger.kernel.org
Cc: pasic@linux.ibm.com, borntraeger@de.ibm.com,
frankja@linux.ibm.com, mst@redhat.com, jasowang@redhat.com,
cohuck@redhat.com, kvm@vger.kernel.org,
linux-s390@vger.kernel.org,
virtualization@lists.linux-foundation.org,
thomas.lendacky@amd.com, david@gibson.dropbear.id.au,
linuxram@us.ibm.com, heiko.carstens@de.ibm.com,
gor@linux.ibm.com
Subject: [PATCH v3 1/1] s390: virtio: let arch accept devices without IOMMU feature
Date: Wed, 17 Jun 2020 12:43:57 +0200 [thread overview]
Message-ID: <1592390637-17441-2-git-send-email-pmorel@linux.ibm.com> (raw)
In-Reply-To: <1592390637-17441-1-git-send-email-pmorel@linux.ibm.com>
An architecture protecting the guest memory against unauthorized host
access may want to enforce VIRTIO I/O device protection through the
use of VIRTIO_F_IOMMU_PLATFORM.
Let's give a chance to the architecture to accept or not devices
without VIRTIO_F_IOMMU_PLATFORM.
Signed-off-by: Pierre Morel <pmorel@linux.ibm.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
---
arch/s390/mm/init.c | 6 ++++++
drivers/virtio/virtio.c | 22 ++++++++++++++++++++++
include/linux/virtio.h | 2 ++
3 files changed, 30 insertions(+)
diff --git a/arch/s390/mm/init.c b/arch/s390/mm/init.c
index 6dc7c3b60ef6..215070c03226 100644
--- a/arch/s390/mm/init.c
+++ b/arch/s390/mm/init.c
@@ -45,6 +45,7 @@
#include <asm/kasan.h>
#include <asm/dma-mapping.h>
#include <asm/uv.h>
+#include <linux/virtio.h>
pgd_t swapper_pg_dir[PTRS_PER_PGD] __section(.bss..swapper_pg_dir);
@@ -161,6 +162,11 @@ bool force_dma_unencrypted(struct device *dev)
return is_prot_virt_guest();
}
+int arch_needs_virtio_iommu_platform(struct virtio_device *dev)
+{
+ return is_prot_virt_guest();
+}
+
/* protected virtualization */
static void pv_init(void)
{
diff --git a/drivers/virtio/virtio.c b/drivers/virtio/virtio.c
index a977e32a88f2..aa8e01104f86 100644
--- a/drivers/virtio/virtio.c
+++ b/drivers/virtio/virtio.c
@@ -167,6 +167,21 @@ void virtio_add_status(struct virtio_device *dev, unsigned int status)
}
EXPORT_SYMBOL_GPL(virtio_add_status);
+/*
+ * arch_needs_virtio_iommu_platform - provide arch specific hook when finalizing
+ * features for VIRTIO device dev
+ * @dev: the VIRTIO device being added
+ *
+ * Permits the platform to provide architecture specific functionality when
+ * devices features are finalized. This is the default implementation.
+ * Architecture implementations can override this.
+ */
+
+int __weak arch_needs_virtio_iommu_platform(struct virtio_device *dev)
+{
+ return 0;
+}
+
int virtio_finalize_features(struct virtio_device *dev)
{
int ret = dev->config->finalize_features(dev);
@@ -179,6 +194,13 @@ int virtio_finalize_features(struct virtio_device *dev)
if (!virtio_has_feature(dev, VIRTIO_F_VERSION_1))
return 0;
+ if (arch_needs_virtio_iommu_platform(dev) &&
+ !virtio_has_feature(dev, VIRTIO_F_IOMMU_PLATFORM)) {
+ dev_warn(&dev->dev,
+ "virtio: device must provide VIRTIO_F_IOMMU_PLATFORM\n");
+ return -ENODEV;
+ }
+
virtio_add_status(dev, VIRTIO_CONFIG_S_FEATURES_OK);
status = dev->config->get_status(dev);
if (!(status & VIRTIO_CONFIG_S_FEATURES_OK)) {
diff --git a/include/linux/virtio.h b/include/linux/virtio.h
index a493eac08393..e8526ae3463e 100644
--- a/include/linux/virtio.h
+++ b/include/linux/virtio.h
@@ -195,4 +195,6 @@ void unregister_virtio_driver(struct virtio_driver *drv);
#define module_virtio_driver(__virtio_driver) \
module_driver(__virtio_driver, register_virtio_driver, \
unregister_virtio_driver)
+
+int arch_needs_virtio_iommu_platform(struct virtio_device *dev);
#endif /* _LINUX_VIRTIO_H */
--
2.25.1
next prev parent reply other threads:[~2020-06-17 10:44 UTC|newest]
Thread overview: 25+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-06-17 10:43 [PATCH v3 0/1] s390: virtio: let arch choose to accept devices without IOMMU feature Pierre Morel
2020-06-17 10:43 ` Pierre Morel [this message]
2020-06-17 11:22 ` [PATCH v3 1/1] s390: virtio: let arch " Heiko Carstens
2020-06-17 11:59 ` Pierre Morel
2020-06-17 13:36 ` Tom Lendacky
2020-06-17 14:12 ` Pierre Morel
2020-06-17 22:29 ` Halil Pasic
2020-06-19 9:20 ` Cornelia Huck
2020-06-19 12:02 ` Halil Pasic
2020-06-29 13:15 ` Pierre Morel
2020-06-29 13:14 ` Pierre Morel
2020-06-29 13:44 ` Cornelia Huck
2020-06-29 16:10 ` Pierre Morel
2020-06-29 13:21 ` Pierre Morel
2020-06-29 15:57 ` Michael S. Tsirkin
2020-06-29 16:05 ` Cornelia Huck
2020-07-02 13:03 ` Pierre Morel
2020-07-06 13:37 ` Pierre Morel
2020-07-06 14:33 ` Cornelia Huck
2020-07-06 15:01 ` Pierre Morel
2020-06-29 16:09 ` Pierre Morel
2020-06-29 16:09 ` Michael S. Tsirkin
2020-06-29 16:48 ` Pierre Morel
2020-06-29 21:18 ` Michael S. Tsirkin
2020-06-30 7:08 ` Cornelia Huck
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=1592390637-17441-2-git-send-email-pmorel@linux.ibm.com \
--to=pmorel@linux.ibm.com \
--cc=borntraeger@de.ibm.com \
--cc=cohuck@redhat.com \
--cc=david@gibson.dropbear.id.au \
--cc=frankja@linux.ibm.com \
--cc=gor@linux.ibm.com \
--cc=heiko.carstens@de.ibm.com \
--cc=jasowang@redhat.com \
--cc=kvm@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-s390@vger.kernel.org \
--cc=linuxram@us.ibm.com \
--cc=mst@redhat.com \
--cc=pasic@linux.ibm.com \
--cc=thomas.lendacky@amd.com \
--cc=virtualization@lists.linux-foundation.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).