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

From: Greg KH
Date: Mon May 17 2021 - 03:08:00 EST


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
> beginning.
>
> Suggested-by: Ashok Raj <ashok.raj@xxxxxxxxx>
> Signed-off-by: Lu Baolu <baolu.lu@xxxxxxxxxxxxxxx>
> Link: https://lore.kernel.org/r/20210115004202.953965-1-baolu.lu@xxxxxxxxxxxxxxx
> 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(-)
>
> [Note:
> - This is a reworked patch of
> https://lore.kernel.org/stable/20210512144819.664462530@xxxxxxxxxxxxxxxxxxx/T/#m65267f0a0091c2fcbde097cea91089775908faad.
> - It aims to fix a reported issue of
> https://bugzilla.kernel.org/show_bug.cgi?id=213077.
> - Please help to review and test.]

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

thanks,

greg k-h