Re: [PATCH v2 00/24] iommu: Refactor DMA domain strictness

Robin Murphy
2021-07-29T15:47:21Z

On 2021-07-29 16:04, Heiko Stübner wrote:
> Hi Robin,
>
> Am Mittwoch, 28. Juli 2021, 17:58:21 CEST schrieb Robin Murphy:
>> Hi all,
>>
>> Here's v2 where things start to look more realistic, hence the expanded
>> CC list. The patches are now based on the current iommu/core branch to
>> take John's iommu_set_dma_strict() cleanup into account.
>>
>> The series remiains in two (or possibly 3) logical parts - for people
>> CC'd on cookie cleanup patches, the later parts should not affect you
>> since your drivers don't implement non-strict mode anyway; the cleanup
>> is all pretty straightforward, but please do yell at me if I've managed
>> to let a silly mistake slip through and broken your driver.
>>
>> This time I have also build-tested x86 as well as arm64 :)
>
> TL;DR: arm64 yay, arm32 nay ;-)

Cheers Heiko!

> testcase:
> 5.14-rc3
> + iommu/next
> + patches 1+8 (the ones you cc'd me on)
> iommu: Pull IOVA cookie management into the core
> iommu/rockchip: Drop IOVA cookie management
>
> rk3399+hdmi (puma): boots with graphics
> rk3399+edp (kevin): boots with graphics
> px30+dsi (minievb): boots with graphics
>
> rk3288 (arm32, veyron-pinky): hangs when trying to start the rockchip-drm
> at some points the rest of the system recovers and fills the log with
>
> [ 47.193776] [drm:drm_crtc_commit_wait] *ERROR* flip_done timed out
> [ 47.193867] [drm:drm_atomic_helper_wait_for_dependencies] *ERROR* [PLANE:31:plane-0] commit wait timed out
> [ 57.433743] [drm:drm_crtc_commit_wait] *ERROR* flip_done timed out
> [ 57.433828] [drm:drm_atomic_helper_wait_for_dependencies] *ERROR* [PLANE:40:plane-4] commit wait timed out
>
> spews
>
> testcase 2:
> 5.14-rc3
> + iommu/next
>
> all works fine on both arm32+arm64
>
>
> That whole iommu voodoo is a bit over my head right now, so I'm not sure
> what to poke to diagnose this.

Dang, this wasn't supposed to affect 32-bit Arm at all, since that
doesn't touch any of the default domain stuff either way. I have both my
RK3288 box (which IIRC doesn't currently boot) and an Odroid-U3 in the
"desk pile" right in front of me, so at worst I'll try bringing one of
those to life to see what silly thing I have indeed done to break 32-bit.

I have a vague idea forming already, which suggests that it might get
better again once patch #12 is applied, but even if so there's no excuse
not to be bisectable, so I need to dig in and fix it - many thanks for
yelling as requested :D

Robin.

>
>
> Heiko
>
>
>> Changes in v2:
>>
>> - Add iommu_is_dma_domain() helper to abstract flag check (and help
>> avoid silly typos like the one in v1).
>> - Tweak a few commit messages for spelling and (hopefully) clarity.
>> - Move the iommu_create_device_direct_mappings() update to patch #14
>> where it should have been.
>> - Rewrite patch #20 as a conversion of the now-existing option.
>> - Clean up the ops->flush_iotlb_all check which is also made redundant
>> by the new domain type
>> - Add patch #24, which is arguably tangential, but it was something I
>> spotted during the rebase, so...
>>
>> Once again, the whole lot is available on a branch here:
>>
>> https://gitlab.arm.com/linux-arm/linux-rm/-/tree/iommu/fq
>>
>> Thanks,
>> Robin.
>>
>>
>> CC: Marek Szyprowski <m.szyprowski@samsung.com>
>> CC: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
>> CC: Geert Uytterhoeven <geert+renesas@glider.be>
>> CC: Yong Wu <yong.wu@mediatek.com>
>> CC: Heiko Stuebner <heiko@sntech.de>
>> CC: Chunyan Zhang <chunyan.zhang@unisoc.com>
>> CC: Chunyan Zhang <chunyan.zhang@unisoc.com>
>> CC: Maxime Ripard <mripard@kernel.org>
>> CC: Jean-Philippe Brucker <jean-philippe@linaro.org>
>>
>> Robin Murphy (24):
>> iommu: Pull IOVA cookie management into the core
>> iommu/amd: Drop IOVA cookie management
>> iommu/arm-smmu: Drop IOVA cookie management
>> iommu/vt-d: Drop IOVA cookie management
>> iommu/exynos: Drop IOVA cookie management
>> iommu/ipmmu-vmsa: Drop IOVA cookie management
>> iommu/mtk: Drop IOVA cookie management
>> iommu/rockchip: Drop IOVA cookie management
>> iommu/sprd: Drop IOVA cookie management
>> iommu/sun50i: Drop IOVA cookie management
>> iommu/virtio: Drop IOVA cookie management
>> iommu/dma: Unexport IOVA cookie management
>> iommu/dma: Remove redundant "!dev" checks
>> iommu: Introduce explicit type for non-strict DMA domains
>> iommu/amd: Prepare for multiple DMA domain types
>> iommu/arm-smmu: Prepare for multiple DMA domain types
>> iommu/vt-d: Prepare for multiple DMA domain types
>> iommu: Express DMA strictness via the domain type
>> iommu: Expose DMA domain strictness via sysfs
>> iommu: Merge strictness and domain type configs
>> iommu/dma: Factor out flush queue init
>> iommu: Allow enabling non-strict mode dynamically
>> iommu/arm-smmu: Allow non-strict in pgtable_quirks interface
>> iommu: Only log strictness for DMA domains
>>
>> .../ABI/testing/sysfs-kernel-iommu_groups | 2 +
>> drivers/iommu/Kconfig | 80 +++++++++----------
>> drivers/iommu/amd/iommu.c | 21 +----
>> drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c | 25 ++++--
>> drivers/iommu/arm/arm-smmu/arm-smmu.c | 29 ++++---
>> drivers/iommu/arm/arm-smmu/qcom_iommu.c | 8 --
>> drivers/iommu/dma-iommu.c | 44 +++++-----
>> drivers/iommu/exynos-iommu.c | 18 +----
>> drivers/iommu/intel/iommu.c | 23 ++----
>> drivers/iommu/iommu.c | 53 +++++++-----
>> drivers/iommu/ipmmu-vmsa.c | 27 +------
>> drivers/iommu/mtk_iommu.c | 6 --
>> drivers/iommu/rockchip-iommu.c | 11 +--
>> drivers/iommu/sprd-iommu.c | 6 --
>> drivers/iommu/sun50i-iommu.c | 12 +--
>> drivers/iommu/virtio-iommu.c | 8 --
>> include/linux/dma-iommu.h | 9 ++-
>> include/linux/iommu.h | 15 +++-
>> 18 files changed, 171 insertions(+), 226 deletions(-)
>>
>>