On Thu, 10 Mar 2016 12:13:28 -0500
Sinan Kaya [off-list ref] wrote:

On 3/10/2016 5:11 AM, Eric Auger wrote:

quoted

Hi Sinan,
On 03/08/2016 04:33 PM, Sinan Kaya wrote:

quoted

The  code is using the compatible DT string to associate a reset driver with
the actual device itself. The compatible string does not exist on ACPI
based systems. HID is the unique identifier for a device driver instead.
The change allows a driver to register with DT compatible string or ACPI
HID and then match the object with one of these conditions.

Rules for loading the reset driver are as follow:
- ACPI HID needs match for ACPI systems
- DT compat needs to match for OF systems

Tested-by: Eric Auger <redacted> (device tree only)
Tested-by: Shanker Donthineni <redacted> (ACPI only)
Signed-off-by: Sinan Kaya <redacted>
---
 .../vfio/platform/reset/vfio_platform_amdxgbe.c    |   4 +-
 .../platform/reset/vfio_platform_calxedaxgmac.c    |   4 +-
 drivers/vfio/platform/vfio_platform_common.c       | 112 +++++++++++++++++----
 drivers/vfio/platform/vfio_platform_private.h      |  43 ++++----
 4 files changed, 125 insertions(+), 38 deletions(-)

[...]

quoted

quoted

-	vfio_platform_get_reset(vdev);
+	ret = vfio_platform_get_reset(vdev);
+	if (ret) {
+		iommu_group_put(group);
+		return ret;
+	}

This change is not related to your commit message. Also here you change
the use model of VFIO platform and forbid any usage if no reset module
is available, right? I don't think this is something we discussed and I
think it removes some flexibility. Currently a warning is emitted in
case we don't have a reset function.

Well, I haven't seen that warning during testing. I was trying to be more 
proactive.

I'm fine removing these checks but not having a reset driver needs a really
big warning here.

This code really needs to be moved to a separate patch, but I agree
overall: a reset function should be made mandatory - I cannot imagine
trusting the HW to be left in a sane state after being used by a guest.

Thanks,

	M.
-- 
Jazz is not dead. It just smells funny.