[PATCH v6 01/12] iommu/exynos: add missing cache flush for removed pagetable entries

[PATCH v6 01/12] iommu/exynos: add missing cache flush for removed pagetable entries

[Cho KyongHo]

This commit adds cache flush for removed small page 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.

Signed-off-by: KyongHo Cho <pullip.cho@samsung.com>
---
 drivers/iommu/exynos-iommu.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/iommu/exynos-iommu.c b/drivers/iommu/exynos-iommu.c
index 7fe44f8..b96f3b9 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;
+		pgtable_flush(ent, ent + 1);
 		size = SPAGE_SIZE;
 		priv->lv2entcnt[lv1ent_offset(iova)] += 1;
 		goto done;
@@ -1011,6 +1012,7 @@ 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;
-- 
1.8.0

Re: [PATCH v6 01/12] iommu/exynos: add missing cache flush for removed pagetable entries

[Grant Grundler]

On Tuesday, December 25, 2012 6:00:01 PM UTC-8, Cho KyongHo wrote:
> This commit adds cache flush for removed small page 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.

KyongHo,
It appears this patch was never applied and got caught up in the
device tree binding discussion. AFAICT, this patch is still necessary.
Can you resubmit this patch separately. Or ok if I do?

Original patch is here:
    https://patchwork.kernel.org/patch/1910261/

thanks,
grant

Re: [PATCH v6 01/12] iommu/exynos: add missing cache flush for removed pagetable entries

[Grant Grundler]

-linux-arm (wrong email address - sorry)

On Mon, Jul 1, 2013 at 6:49 PM, Grant Grundler <grundler@chromium.org> wrote:
> On Tuesday, December 25, 2012 6:00:01 PM UTC-8, Cho KyongHo wrote:
>> This commit adds cache flush for removed small page 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.
>
> KyongHo,
> It appears this patch was never applied and got caught up in the
> device tree binding discussion. AFAICT, this patch is still necessary.
> Can you resubmit this patch separately. Or ok if I do?
>
> Original patch is here:
>     https://patchwork.kernel.org/patch/1910261/
>
> thanks,
> grant

Re: [PATCH v6 01/12] iommu/exynos: add missing cache flush for removed pagetable entries

[Grant Grundler]

Ping?

On Mon, Jul 1, 2013 at 6:49 PM, Grant Grundler <grundler@chromium.org> wrote:
> On Tuesday, December 25, 2012 6:00:01 PM UTC-8, Cho KyongHo wrote:
>> This commit adds cache flush for removed small page 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.
>
> KyongHo,
> It appears this patch was never applied and got caught up in the
> device tree binding discussion. AFAICT, this patch is still necessary.
> Can you resubmit this patch separately. Or ok if I do?
>
> Original patch is here:
>     https://patchwork.kernel.org/patch/1910261/
>
> thanks,
> grant

RE: [PATCH v6 01/12] iommu/exynos: add missing cache flush for removed pagetable entries

[Cho KyongHo]

> From: grundler@google.com [mailto:grundler@google.com] On Behalf Of Grant Grundler
> Sent: Thursday, July 04, 2013 5:44 AM
> 
> Ping?
Hi.

Sorry for late update the patch set.
I am still working on the patch set when I am free.
Implementation of the updated patch set has been finished but not tested yet.

I will post the patches after simple test :)

Thank you.
> 
> On Mon, Jul 1, 2013 at 6:49 PM, Grant Grundler <grundler@chromium.org> wrote:
> > On Tuesday, December 25, 2012 6:00:01 PM UTC-8, Cho KyongHo wrote:
> >> This commit adds cache flush for removed small page 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.
> >
> > KyongHo,
> > It appears this patch was never applied and got caught up in the
> > device tree binding discussion. AFAICT, this patch is still necessary.
> > Can you resubmit this patch separately. Or ok if I do?
> >
> > Original patch is here:
> >     https://patchwork.kernel.org/patch/1910261/
> >
> > thanks,
> > grant

Re: [PATCH v6 01/12] iommu/exynos: add missing cache flush for removed pagetable entries

[Grant Grundler]

On Thu, Jul 4, 2013 at 4:20 AM, Cho KyongHo <pullip.cho@samsung.com> wrote:
...
> I am still working on the patch set when I am free.
> Implementation of the updated patch set has been finished but not tested yet.
>
> I will post the patches after simple test :)

Ok - thanks Cho!

If you'd like me to test, please post a "RFC" (request for comment)
version that hasn't yet been tested. You don't have to do everything
yourself. :)

cheers,
grant

Re: [PATCH v6 01/12] iommu/exynos: add missing cache flush for removed pagetable entries

[Grant Grundler]

On Mon, Jul 8, 2013 at 11:21 AM, Grant Grundler <grundler@chromium.org> wrote:
> On Thu, Jul 4, 2013 at 4:20 AM, Cho KyongHo <pullip.cho@samsung.com> wrote:
> ...
>> I am still working on the patch set when I am free.
>> Implementation of the updated patch set has been finished but not tested yet.
>>
>> I will post the patches after simple test :)
>
> Ok - thanks Cho!
>
> If you'd like me to test, please post a "RFC" (request for comment)
> version that hasn't yet been tested. You don't have to do everything
> yourself. :)

Nevermind...I'm catching on email in reverse and see that you've
already posted the patches!

I'll try to test those today. :)

thanks!
grant