Re: [PATCH v1] iommu/ipmmu-vmsa: Set context_id to non-existent value if allocation failed

[Laurent Pinchart <laurent.pinchart-ryLnwIuWjnjg/C1BVhZhaw@public.gmane.org>]

Hi Joerg,

On Tuesday, 22 August 2017 17:24:30 EEST Joerg Roedel wrote:
> On Mon, Aug 21, 2017 at 03:40:41PM +0300, Oleksandr Tyshchenko wrote:
> > From: Oleksandr Tyshchenko <oleksandr_tyshchenko-uRwfk40T5oI@public.gmane.org>
> > 
> > In ipmmu_domain_init_context() we are trying to allocate context and
> > if allocation fails we will call free_io_pgtable_ops(),
> > but "domain->context_id" hasn't been initialized yet (likely it is 0
> > because of kzalloc). Having the following call stack:
> > free_io_pgtable_ops() -> io_pgtable_tlb_flush_all() ->
> > ipmmu_tlb_flush_all() -> ipmmu_tlb_invalidate()
> > we will get a mistaken cache flush for a context pointed by
> > uninitialized "domain->context_id".
> > 
> > So, set context_id to non-existent value (IPMMU_CTX_MAX) before calling
> > free_io_pgtable_ops() and check it for a valid value (< IPMMU_CTX_MAX)
> > before calling ipmmu_tlb_invalidate().
> > 
> > Signed-off-by: Oleksandr Tyshchenko <oleksandr_tyshchenko-uRwfk40T5oI@public.gmane.org>
> > ---
> > 
> >  drivers/iommu/ipmmu-vmsa.c | 4 ++++
> >  1 file changed, 4 insertions(+)
> 
> Applied, thanks.

It would be nice to give reviewers a week before applying a patch, especially 
when it has no review at all.

-- 
Regards,

Laurent Pinchart