diff mbox

[v9,02/16] iommu/exynos: add missing cache flush for removed page table entries

Message ID 002601ce941a$e987ba50$bc972ef0$@samsung.com (mailing list archive)
State New, archived
Headers show

Commit Message

Cho KyongHo Aug. 8, 2013, 9:37 a.m. UTC
This commit adds cache flush for removed small and large page entries
in exynos_iommu_unmap(). Missing cache flush of removed page table
entries can cause missing page fault interrupt when a master IP
accesses an unmapped area.

Tested-by: Grant Grundler <grundler@chromium.org>
Signed-off-by: Cho KyongHo <pullip.cho@samsung.com>
---
 drivers/iommu/exynos-iommu.c |    2 ++
 1 files changed, 2 insertions(+), 0 deletions(-)

Comments

Tomasz Figa Aug. 8, 2013, 1:44 p.m. UTC | #1
On Thursday 08 of August 2013 18:37:34 Cho KyongHo wrote:
> This commit adds cache flush for removed small and large page entries
> in exynos_iommu_unmap(). Missing cache flush of removed page table
> entries can cause missing page fault interrupt when a master IP
> accesses an unmapped area.
> 
> Tested-by: Grant Grundler <grundler@chromium.org>
> Signed-off-by: Cho KyongHo <pullip.cho@samsung.com>
> ---
>  drivers/iommu/exynos-iommu.c |    2 ++
>  1 files changed, 2 insertions(+), 0 deletions(-)
> 
> diff --git a/drivers/iommu/exynos-iommu.c b/drivers/iommu/exynos-iommu.c
> index 233f382..d545a25 100644
> --- a/drivers/iommu/exynos-iommu.c
> +++ b/drivers/iommu/exynos-iommu.c
> @@ -1002,6 +1002,7 @@ static size_t exynos_iommu_unmap(struct
> iommu_domain *domain, if (lv2ent_small(ent)) {
>  		*ent = 0;
>  		size = SPAGE_SIZE;
> +		pgtable_flush(ent, ent + 1);
>  		priv->lv2entcnt[lv1ent_offset(iova)] += 1;
>  		goto done;
>  	}
> @@ -1010,6 +1011,7 @@ static size_t exynos_iommu_unmap(struct
> iommu_domain *domain, BUG_ON(size < LPAGE_SIZE);
> 
>  	memset(ent, 0, sizeof(*ent) * SPAGES_PER_LPAGE);
> +	pgtable_flush(ent, ent + SPAGES_PER_LPAGE);
> 
>  	size = LPAGE_SIZE;
>  	priv->lv2entcnt[lv1ent_offset(iova)] += SPAGES_PER_LPAGE;

Looks reasonable.

Reviewed-by: Tomasz Figa <t.figa@samsung.com>

Best regards,
Tomasz
Cho KyongHo Aug. 9, 2013, 4:02 a.m. UTC | #2
On Thu, 08 Aug 2013 15:44:09 +0200, Tomasz Figa wrote:
> On Thursday 08 of August 2013 18:37:34 Cho KyongHo wrote:
> > This commit adds cache flush for removed small and large page entries
> > in exynos_iommu_unmap(). Missing cache flush of removed page table
> > entries can cause missing page fault interrupt when a master IP
> > accesses an unmapped area.
> > 
> > Tested-by: Grant Grundler <grundler@chromium.org>
> > Signed-off-by: Cho KyongHo <pullip.cho@samsung.com>
> > ---
> >  drivers/iommu/exynos-iommu.c |    2 ++
> >  1 files changed, 2 insertions(+), 0 deletions(-)
> > 
> > diff --git a/drivers/iommu/exynos-iommu.c b/drivers/iommu/exynos-iommu.c
> > index 233f382..d545a25 100644
> > --- a/drivers/iommu/exynos-iommu.c
> > +++ b/drivers/iommu/exynos-iommu.c
> > @@ -1002,6 +1002,7 @@ static size_t exynos_iommu_unmap(struct
> > iommu_domain *domain, if (lv2ent_small(ent)) {
> >  		*ent = 0;
> >  		size = SPAGE_SIZE;
> > +		pgtable_flush(ent, ent + 1);
> >  		priv->lv2entcnt[lv1ent_offset(iova)] += 1;
> >  		goto done;
> >  	}
> > @@ -1010,6 +1011,7 @@ static size_t exynos_iommu_unmap(struct
> > iommu_domain *domain, BUG_ON(size < LPAGE_SIZE);
> > 
> >  	memset(ent, 0, sizeof(*ent) * SPAGES_PER_LPAGE);
> > +	pgtable_flush(ent, ent + SPAGES_PER_LPAGE);
> > 
> >  	size = LPAGE_SIZE;
> >  	priv->lv2entcnt[lv1ent_offset(iova)] += SPAGES_PER_LPAGE;
> 
> Looks reasonable.
> 
> Reviewed-by: Tomasz Figa <t.figa@samsung.com>
> 

Thanks.

KyongHo.
> Best regards,
> Tomasz
>
diff mbox

Patch

diff --git a/drivers/iommu/exynos-iommu.c b/drivers/iommu/exynos-iommu.c
index 233f382..d545a25 100644
--- a/drivers/iommu/exynos-iommu.c
+++ b/drivers/iommu/exynos-iommu.c
@@ -1002,6 +1002,7 @@  static size_t exynos_iommu_unmap(struct iommu_domain *domain,
 	if (lv2ent_small(ent)) {
 		*ent = 0;
 		size = SPAGE_SIZE;
+		pgtable_flush(ent, ent + 1);
 		priv->lv2entcnt[lv1ent_offset(iova)] += 1;
 		goto done;
 	}
@@ -1010,6 +1011,7 @@  static size_t exynos_iommu_unmap(struct iommu_domain *domain,
 	BUG_ON(size < LPAGE_SIZE);
 
 	memset(ent, 0, sizeof(*ent) * SPAGES_PER_LPAGE);
+	pgtable_flush(ent, ent + SPAGES_PER_LPAGE);
 
 	size = LPAGE_SIZE;
 	priv->lv2entcnt[lv1ent_offset(iova)] += SPAGES_PER_LPAGE;