Re: [PATCH 2/2] iommu/vt-d: Remove dead code in device_notifier

From: Jerry Hoemann
Date: Wed Dec 17 2014 - 16:41:49 EST


On Wed, Dec 17, 2014 at 11:43:37AM +0100, Joerg Roedel wrote:
> From: Joerg Roedel <jroedel@xxxxxxx>
>
> This code only runs when action == BUS_NOTIFY_REMOVED_DEVICE,
> so it can't be BUS_NOTIFY_DEL_DEVICE.
>
> Signed-off-by: Joerg Roedel <jroedel@xxxxxxx>
> ---
> drivers/iommu/intel-iommu.c | 8 --------
> 1 file changed, 8 deletions(-)
>
> diff --git a/drivers/iommu/intel-iommu.c b/drivers/iommu/intel-iommu.c
> index 7610121..40dfbc0 100644
> --- a/drivers/iommu/intel-iommu.c
> +++ b/drivers/iommu/intel-iommu.c
> @@ -4029,14 +4029,6 @@ static int device_notifier(struct notifier_block *nb,
> if (action != BUS_NOTIFY_REMOVED_DEVICE)
> return 0;
>
> - /*
> - * If the device is still attached to a device driver we can't
> - * tear down the domain yet as DMA mappings may still be in use.
> - * Wait for the BUS_NOTIFY_UNBOUND_DRIVER event to do that.
> - */
> - if (action == BUS_NOTIFY_DEL_DEVICE && dev->driver != NULL)
> - return 0;
> -
> domain = find_domain(dev);
> if (!domain)
> return 0;
> --
> 1.9.1

Joerg,

Tested this along w/ other patch of the set.

Instrumentation showed that the removed code wouldn't have been executed
during VM power on/power off.

Thanks!

Tested-by: Jerry Hoemann <jerry.hoemann@xxxxxx>


--

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Jerry Hoemann Software Engineer Hewlett-Packard

3404 E Harmony Rd. MS 36 phone: (970) 898-1022
Ft. Collins, CO 80528 FAX: (970) 898-0707
email: jerry.hoemann@xxxxxx
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