lkml.org 
[lkml]   [2017]   [Jan]   [10]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
SubjectRe: [PATCH v7 08/19] iommu: Implement reserved_regions iommu-group sysfs file
From
Date
Hi Joerg,
On 10/01/2017 18:14, Joerg Roedel wrote:
> On Tue, Jan 10, 2017 at 05:20:34PM +0100, Auger Eric wrote:
>> The /sys/kernel/iommu_groups/n directory seems to be removed before this
>> gets called and this may produce a WARNING when devices get removed from
>> the group. I intend to remove the call since I have the feeling
>> everything gets cleaned up properly.
>
> A feeling is not enough, please check that in the code.

So my understanding is on group's kobject_release we have:
kobject_release
|_ kobject_cleanup
|_ kobject_del
|_ sysfs_remove_dir
|_ kernfs_remove
|_ _kernfs_remove
../..
|_ ktype release (iommu_group_release)

_kernfs_remove() calls kernfs_put() on all descendant nodes, leading to
the whole directory cleanup.

In iommu_group_release I called sysfs_remove_file on the
reserved_regions attribute file. My understanding is its job is
identifical as what was done previously and the node was already
destroyed hence the warning.

sysfs_remove_file
|_ sysfs_remove_file_ns
|_ kernfs_remove_by_name_ns
|_kernfs_remove

So my understanding is it is safe to remove it.

Thanks

Eric
>
>
> Joerg
>
>
> _______________________________________________
> linux-arm-kernel mailing list
> linux-arm-kernel@lists.infradead.org
> http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
>

\
 
 \ /
  Last update: 2017-01-10 22:22    [W:0.126 / U:12.008 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site