Re: [PATCH 2/2] iommu/amd: Destroy api_lock mutex when freeing domain

From: Vesely, Jan
Date: Wed Jun 15 2016 - 16:27:34 EST


On Wed, 2016-06-15 at 13:54 +0200, joro@xxxxxxxxxx wrote:
> On Thu, Jun 09, 2016 at 03:48:44PM +0000, Vesely, Jan wrote:
> > On Sat, 2016-05-21 at 14:11 -0400, Jan Vesely wrote:
> > > From: Jan Vesely <jan.vesely@xxxxxxx>
> > >
> > > Signed-off-by: Jan Vesely <jan.vesely@xxxxxxx>
> > > ---
> > > Âdrivers/iommu/amd_iommu.c | 1 +
> > > Â1 file changed, 1 insertion(+)
> > >
> > > diff --git a/drivers/iommu/amd_iommu.c
> > > b/drivers/iommu/amd_iommu.c
> > > index 17c76f2..4ff5e40 100644
> > > --- a/drivers/iommu/amd_iommu.c
> > > +++ b/drivers/iommu/amd_iommu.c
> > > @@ -3016,6 +3016,7 @@ static void protection_domain_free(struct
> > > protection_domain *domain)
> > > Â
> > > Â del_domain_from_list(domain);
> > > Â
> > > + mutex_destroy(&domain->api_lock);
> > > Â if (domain->id)
> > > Â domain_id_free(domain->id);
> > > Â
> >
> > ping
>
> Your patches lack commit messages, please add a more detailed
> description of what you are fixing and why. Please also add 'Fixes:'
> tags when resubmitting. The changes itself look good to me.

There are no specific bugs/oopses that these patches fix (that I'm
aware of). Both were found while I was familiarizing myself with the
code looking for memory corruption (which turned out to be [0]).
Either issue would be very difficult to hit in the wild and
mutex_destroy is empty unless you compile using CONFIG_DEBUG_MUTEXES.

Jan

[0] https://lkml.org/lkml/2016/3/7/1087

>
>
> Joerg
>