From: Sinan Kaya <okaya@codeaurora.org>
To: kvm@vger.kernel.org, timur@codeaurora.org, cov@codeaurora.org,
jcm@redhat.com, alex.williamson@redhat.com,
eric.auger@linaro.org
Cc: linux-acpi@vger.kernel.org, agross@codeaurora.org,
linux-arm-msm@vger.kernel.org,
linux-arm-kernel@lists.infradead.org,
Sinan Kaya <okaya@codeaurora.org>,
Baptiste Reynal <b.reynal@virtualopensystems.com>,
linux-kernel@vger.kernel.org
Subject: [PATCH V7 7/9] vfio, platform: make reset driver a requirement by default
Date: Mon, 13 Jun 2016 00:26:39 -0400 [thread overview]
Message-ID: <1465792001-27960-8-git-send-email-okaya@codeaurora.org> (raw)
In-Reply-To: <1465792001-27960-1-git-send-email-okaya@codeaurora.org>
The code was allowing platform devices to be used without a supporting
VFIO reset driver. The hardware can be left in some inconsistent state
after a guest machine abort.
The reset driver will put the hardware back to safe state and disable
interrupts before returning the control back to the host machine.
Adding a new reset_required kernel module option to AMBA and platform
VFIO drivers with a default value of true.
New requirements are:
1. A reset function needs to be implemented by the corresponding driver
via DT/ACPI.
2. The reset function needs to be discovered via DT/ACPI.
The probe of the driver will fail if any of the above conditions are
not satisfied.
Signed-off-by: Sinan Kaya <okaya@codeaurora.org>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
---
drivers/vfio/platform/vfio_amba.c | 5 +++++
drivers/vfio/platform/vfio_platform.c | 5 +++++
drivers/vfio/platform/vfio_platform_common.c | 22 +++++++++++++++-------
drivers/vfio/platform/vfio_platform_private.h | 1 +
4 files changed, 26 insertions(+), 7 deletions(-)
diff --git a/drivers/vfio/platform/vfio_amba.c b/drivers/vfio/platform/vfio_amba.c
index a66479b..7585902 100644
--- a/drivers/vfio/platform/vfio_amba.c
+++ b/drivers/vfio/platform/vfio_amba.c
@@ -23,6 +23,10 @@
#define DRIVER_AUTHOR "Antonios Motakis <a.motakis@virtualopensystems.com>"
#define DRIVER_DESC "VFIO for AMBA devices - User Level meta-driver"
+static bool reset_required = true;
+module_param(reset_required, bool, 0644);
+MODULE_PARM_DESC(reset_required, "override reset requirement (default: 1)");
+
/* probing devices from the AMBA bus */
static struct resource *get_amba_resource(struct vfio_platform_device *vdev,
@@ -68,6 +72,7 @@ static int vfio_amba_probe(struct amba_device *adev, const struct amba_id *id)
vdev->get_resource = get_amba_resource;
vdev->get_irq = get_amba_irq;
vdev->parent_module = THIS_MODULE;
+ vdev->reset_required = reset_required;
ret = vfio_platform_probe_common(vdev, &adev->dev);
if (ret) {
diff --git a/drivers/vfio/platform/vfio_platform.c b/drivers/vfio/platform/vfio_platform.c
index b1cc3a7..ef89146 100644
--- a/drivers/vfio/platform/vfio_platform.c
+++ b/drivers/vfio/platform/vfio_platform.c
@@ -23,6 +23,10 @@
#define DRIVER_AUTHOR "Antonios Motakis <a.motakis@virtualopensystems.com>"
#define DRIVER_DESC "VFIO for platform devices - User Level meta-driver"
+static bool reset_required = true;
+module_param(reset_required, bool, 0644);
+MODULE_PARM_DESC(reset_required, "override reset requirement (default: 1)");
+
/* probing devices from the linux platform bus */
static struct resource *get_platform_resource(struct vfio_platform_device *vdev,
@@ -66,6 +70,7 @@ static int vfio_platform_probe(struct platform_device *pdev)
vdev->get_resource = get_platform_resource;
vdev->get_irq = get_platform_irq;
vdev->parent_module = THIS_MODULE;
+ vdev->reset_required = reset_required;
ret = vfio_platform_probe_common(vdev, &pdev->dev);
if (ret)
diff --git a/drivers/vfio/platform/vfio_platform_common.c b/drivers/vfio/platform/vfio_platform_common.c
index 0ea8c26..d84c399 100644
--- a/drivers/vfio/platform/vfio_platform_common.c
+++ b/drivers/vfio/platform/vfio_platform_common.c
@@ -128,10 +128,10 @@ static bool vfio_platform_has_reset(struct vfio_platform_device *vdev)
return vdev->of_reset ? true : false;
}
-static void vfio_platform_get_reset(struct vfio_platform_device *vdev)
+static int vfio_platform_get_reset(struct vfio_platform_device *vdev)
{
if (vdev->acpihid)
- return;
+ return vfio_platform_acpi_has_reset(vdev) ? 0 : -ENOENT;
vdev->of_reset = vfio_platform_lookup_reset(vdev->compat,
&vdev->reset_module);
@@ -140,6 +140,8 @@ static void vfio_platform_get_reset(struct vfio_platform_device *vdev)
vdev->of_reset = vfio_platform_lookup_reset(vdev->compat,
&vdev->reset_module);
}
+
+ return vdev->of_reset ? 0 : -ENOENT;
}
static void vfio_platform_put_reset(struct vfio_platform_device *vdev)
@@ -670,16 +672,22 @@ int vfio_platform_probe_common(struct vfio_platform_device *vdev,
}
ret = vfio_add_group_dev(dev, &vfio_platform_ops, vdev);
- if (ret) {
- iommu_group_put(group);
- return ret;
- }
+ if (ret)
+ goto out;
- vfio_platform_get_reset(vdev);
+ ret = vfio_platform_get_reset(vdev);
+ if (ret && vdev->reset_required) {
+ pr_err("vfio: no reset function found for device %s\n",
+ vdev->name);
+ goto out;
+ }
mutex_init(&vdev->igate);
return 0;
+out:
+ iommu_group_put(group);
+ return ret;
}
EXPORT_SYMBOL_GPL(vfio_platform_probe_common);
diff --git a/drivers/vfio/platform/vfio_platform_private.h b/drivers/vfio/platform/vfio_platform_private.h
index ba9e4f8..68fbc00 100644
--- a/drivers/vfio/platform/vfio_platform_private.h
+++ b/drivers/vfio/platform/vfio_platform_private.h
@@ -50,6 +50,7 @@ struct vfio_platform_region {
};
struct vfio_platform_device {
+ bool reset_required;
struct vfio_platform_region *regions;
u32 num_regions;
struct vfio_platform_irq *irqs;
--
1.8.2.1
next prev parent reply other threads:[~2016-06-13 4:27 UTC|newest]
Thread overview: 17+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <1465792001-27960-1-git-send-email-okaya@codeaurora.org>
2016-06-13 4:26 ` [PATCH V7 1/9] vfio: platform: rename reset function Sinan Kaya
2016-06-13 4:26 ` [PATCH V7 2/9] vfio: platform: move reset call to a common function Sinan Kaya
2016-06-13 4:26 ` [PATCH V7 3/9] vfio: platform: determine reset capability Sinan Kaya
2016-06-13 4:26 ` [PATCH V7 4/9] vfio: platform: add support for ACPI probe Sinan Kaya
2016-06-13 4:26 ` [PATCH V7 5/9] vfio: platform: add extra debug info argument to call reset Sinan Kaya
2016-06-13 4:26 ` [PATCH V7 6/9] vfio: platform: call _RST method when using ACPI Sinan Kaya
2016-06-23 18:59 ` Alex Williamson
2016-06-23 19:07 ` Alex Williamson
2016-06-23 19:14 ` Sinan Kaya
2016-07-13 19:39 ` Sinan Kaya
2016-07-13 20:11 ` Alex Williamson
2016-06-13 4:26 ` Sinan Kaya [this message]
2016-06-16 8:15 ` [PATCH V7 7/9] vfio, platform: make reset driver a requirement by default Auger Eric
2016-06-16 17:08 ` Sinan Kaya
2016-06-13 4:26 ` [PATCH V7 8/9] vfio: platform: check reset call return code during open Sinan Kaya
2016-06-15 20:08 ` Auger Eric
2016-06-13 4:26 ` [PATCH V7 9/9] vfio: platform: check reset call return code during release Sinan Kaya
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=1465792001-27960-8-git-send-email-okaya@codeaurora.org \
--to=okaya@codeaurora.org \
--cc=agross@codeaurora.org \
--cc=alex.williamson@redhat.com \
--cc=b.reynal@virtualopensystems.com \
--cc=cov@codeaurora.org \
--cc=eric.auger@linaro.org \
--cc=jcm@redhat.com \
--cc=kvm@vger.kernel.org \
--cc=linux-acpi@vger.kernel.org \
--cc=linux-arm-kernel@lists.infradead.org \
--cc=linux-arm-msm@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=timur@codeaurora.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).