Re: [REWORKED PATCH 1/1] iommu/vt-d: Preset Access/Dirty bits for IOVA over FL

From: Lu Baolu
Date: Mon May 17 2021 - 03:52:10 EST

Hi Greg,

On 5/17/21 3:27 PM, Greg KH wrote:
On Mon, May 17, 2021 at 03:17:53PM +0800, Lu Baolu wrote:
Hi Greg,

On 5/17/21 3:07 PM, Greg KH wrote:
On Mon, May 17, 2021 at 11:49:13AM +0800, Lu Baolu wrote:
[ Upstream commit a8ce9ebbecdfda3322bbcece6b3b25888217f8e3 ]

The Access/Dirty bits in the first level page table entry will be set
whenever a page table entry was used for address translation or write
permission was successfully translated. This is always true when using
the first-level page table for kernel IOVA. Instead of wasting hardware
cycles to update the certain bits, it's better to set them up at the

Suggested-by: Ashok Raj <ashok.raj@xxxxxxxxx>
Signed-off-by: Lu Baolu <>
Signed-off-by: Joerg Roedel <jroedel@xxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
drivers/iommu/intel/iommu.c | 14 ++++++++++++--
include/linux/intel-iommu.h | 2 ++
2 files changed, 14 insertions(+), 2 deletions(-)

- This is a reworked patch of
- It aims to fix a reported issue of
- Please help to review and test.]

What stable tree(s) is this supposed to be for?

It's for 5.10.37.

But the above commit is already in 5.10.y. And what about 5.11 and
5.12, were those backports incorrect?

Above commit is now only in v5.10.37. Other 5.10.y are not impacted.

5.11 and 5.12 both have correct backports.


greg k-h

Best regards,