[PATCH v2 00/10] Refine the locking for dev->iommu_group

[Marek Szyprowski]

Hi Jason,

On 08.08.2023 15:00, Jason Gunthorpe wrote:
> On Tue, Aug 08, 2023 at 02:32:48PM +0200, Marek Szyprowski wrote:
>> On 08.08.2023 12:31, Chen-Yu Tsai wrote:
>>> On Mon, Aug 7, 2023 at 8:54 PM Joerg Roedel <joro at 8bytes.org> wrote:
>>>> On Mon, Jul 31, 2023 at 02:50:23PM -0300, Jason Gunthorpe wrote:
>>>>> Jason Gunthorpe (10):
>>>>>     iommu: Remove useless group refcounting
>>>>>     iommu: Add a lockdep assertion for remaining dev->iommu_group reads
>>>>>     iommu: Add generic_single_device_group()
>>>>>     iommu/sun50i: Convert to generic_single_device_group()
>>>>>     iommu/sprd: Convert to generic_single_device_group()
>>>>>     iommu/rockchip: Convert to generic_single_device_group()
>>>>>     iommu/ipmmu-vmsa: Convert to generic_single_device_group()
>>>>>     iommu/omap: Convert to generic_single_device_group()
>>>>>     iommu: Complete the locking for dev->iommu_group
>>>>>     iommu/intel: Fix missing locking for show_device_domain_translation()
>>>>>
>>>>>    drivers/iommu/intel/debugfs.c  |  34 ++++----
>>>>>    drivers/iommu/iommu.c          | 155 +++++++++++++++++++++------------
>>>>>    drivers/iommu/ipmmu-vmsa.c     |  22 ++---
>>>>>    drivers/iommu/omap-iommu.c     |  30 +------
>>>>>    drivers/iommu/omap-iommu.h     |   2 +-
>>>>>    drivers/iommu/rockchip-iommu.c |  22 +----
>>>>>    drivers/iommu/sprd-iommu.c     |  24 +----
>>>>>    drivers/iommu/sun50i-iommu.c   |  29 ++----
>>>>>    include/linux/iommu.h          |   3 +
>>>>>    9 files changed, 138 insertions(+), 183 deletions(-)
>>>> Applied, thanks for the nice cleanup!
>>> This series seems to cause a hung task during boot on MediaTek platforms.
>>> It hangs with next-20230808. Reverting the 10 commits from this series
>>> makes the system boot up again.
>> I confirm that next-20230808 is broken on ARM 32bit based Exynos boards
>> too. Boards lock up very early during boot. I will try to investigate
>> this soon.
> Any of the drivers that use platform device as the iommu_device will
> have a problem, please try:
>
> https://lore.kernel.org/linux-iommu/ZNIz%2FNVLb6WqqvQx@nvidia.com/

I've checked and it doesn't help in my case. I will soon check why.

Best regards
-- 
Marek Szyprowski, PhD
Samsung R&D Institute Poland