Kernel 6.7 regression doesn't boot if using AMD eGPU

From: Eric Wagner
Date: Sat Apr 13 2024 - 18:04:37 EST

On my Thinkpad T14s G3 AMD (Ryzen 7 6850U) laptop connected to an AMD RX 580 in Akitio Node Thunderbolt 3 eGPU. Booting with the eGPU connected hangs on kernels 6.7 and 6.8, but worked on 6.6. For debugging, I find that adding the kernel parameter amd_iommu=off seems to fix the issue and allows booting with the eGPU on 6.7.

I tried bisecting the issue between 6.6 and 6.7 and ended up with: "e8cca466a84a75f8ff2a7a31173c99ee6d1c59d2 is the first bad commit" in the attached. This seems to indicate an amd iommu issue.

Two others also reported the same issue on AMD Ryzen 7 7840 with AMD RX 6000 connected as eGPU (https://gitlab.freedesktop.org/drm/amd/-/issues/3182).

Let me know if you need more information.
Bisecting: 366 revisions left to test after this (roughly 9 steps)
[74e9347ebc5be452935fe4f3eddb150aa5a6f4fe] Merge tag 'loongarch-fixes-6.6-3' of git://git.kernel.org/pub/scm/linux/kernel/git/chenhuacai/linux-loongson
Bisecting: 182 revisions left to test after this (roughly 8 steps)
[f6176471542d991137543af2ef1c18dae3286079] Merge tag 'mtd/fixes-for-6.6-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/mtd/linux
Bisecting: 87 revisions left to test after this (roughly 7 steps)
[fe3cfe869d5e0453754cf2b4c75110276b5e8527] Merge tag 'phy-fixes-6.6' of git://git.kernel.org/pub/scm/linux/kernel/git/phy/linux-phy
Bisecting: 43 revisions left to test after this (roughly 6 steps)
[c76c067e488ccd55734c3e750799caf2c5956db6] s390/pci: Use dma-iommu layer
Bisecting: 27 revisions left to test after this (roughly 5 steps)
[aa5cabc4ce8e6b45d170d162dc54b1bac1767c47] Merge tag 'arm-smmu-updates' of git://git.kernel.org/pub/scm/linux/kernel/git/will/linux into arm/smmu
Bisecting: 14 revisions left to test after this (roughly 4 steps)
[bbc70e0aec287e164344b1a071bd46466a4f29b3] iommu/dart: Remove the force_bypass variable
Bisecting: 9 revisions left to test after this (roughly 3 steps)
[e82c175e63229ea495a0a0b5305a98b5b6ee5346] Revert "iommu/vt-d: Remove unused function"
Bisecting: 5 revisions left to test after this (roughly 2 steps)
[92bce97f0c341d3037b0f364b6839483f6a41cae] s390/pci: Fix reset of IOMMU software counters
Bisecting: 3 revisions left to test after this (roughly 2 steps)
[3613047280ec42a4e1350fdc1a6dd161ff4008cc] Merge tag 'v6.6-rc7' into core
Bisecting: 2 revisions left to test after this (roughly 1 step)
[f7da9c081517daba70f9f9342e09d7a6322ba323] iommu/tegra-smmu: Drop unnecessary error check for for debugfs_create_dir()
Bisecting: 1 revision left to test after this (roughly 1 step)
[9e13ec61de2a51195b122a79461431d8cb99d7b5] iommu/virtio: Add __counted_by for struct viommu_request and use struct_size()
Bisecting: 0 revisions left to test after this (roughly 0 steps)
[6e6c6d6bc6c96c2477ddfea24a121eb5ee12b7a3] iommu: Avoid unnecessary cache invalidations
e8cca466a84a75f8ff2a7a31173c99ee6d1c59d2 is the first bad commit
commit e8cca466a84a75f8ff2a7a31173c99ee6d1c59d2
Merge: 6e6c6d6bc6 f7da9c0815 aa5cabc4ce 9e13ec61de e82c175e63 cedc811c76 3613047280 92bce97f0c
Author: Joerg Roedel <jroedel@xxxxxxx>
Date: Fri Oct 27 09:13:40 2023 +0200

Merge branches 'iommu/fixes', 'arm/tegra', 'arm/smmu', 'virtio', 'x86/vt-d', 'x86/amd', 'core' and 's390' into next

Documentation/admin-guide/kernel-parameters.txt | 9 +-
.../devicetree/bindings/iommu/arm,smmu.yaml | 2 +
arch/arm/configs/multi_v7_defconfig | 1 -
arch/arm/configs/tegra_defconfig | 1 -
arch/powerpc/kernel/iommu.c | 53 +-
arch/s390/include/asm/pci.h | 11 -
arch/s390/include/asm/pci_clp.h | 3 +
arch/s390/include/asm/pci_dma.h | 121 +--
arch/s390/pci/Makefile | 2 +-
arch/s390/pci/pci.c | 35 +-
arch/s390/pci/pci_bus.c | 5 -
arch/s390/pci/pci_debug.c | 12 +-
arch/s390/pci/pci_dma.c | 746 ---------------
arch/s390/pci/pci_event.c | 17 +-
arch/s390/pci/pci_sysfs.c | 19 +-
drivers/iommu/Kconfig | 15 +-
drivers/iommu/Makefile | 1 -
drivers/iommu/amd/Kconfig | 9 -
drivers/iommu/amd/Makefile | 1 -
drivers/iommu/amd/amd_iommu.h | 35 +-
drivers/iommu/amd/amd_iommu_types.h | 52 +-
drivers/iommu/amd/init.c | 117 +--
drivers/iommu/amd/io_pgtable_v2.c | 8 +-
drivers/iommu/amd/iommu.c | 577 +++++-------
drivers/iommu/amd/iommu_v2.c | 996 ---------------------
drivers/iommu/apple-dart.c | 138 +--
drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3-sva.c | 71 +-
drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c | 251 +++---
drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h | 17 +-
drivers/iommu/arm/arm-smmu/arm-smmu-qcom.c | 2 +
drivers/iommu/arm/arm-smmu/qcom_iommu.c | 45 +-
drivers/iommu/dma-iommu.c | 200 ++++-
drivers/iommu/exynos-iommu.c | 83 +-
drivers/iommu/fsl_pamu_domain.c | 41 +-
drivers/iommu/intel/debugfs.c | 215 ++++-
drivers/iommu/intel/iommu.c | 19 +-
drivers/iommu/intel/iommu.h | 14 +
drivers/iommu/iommu.c | 455 +++++-----
drivers/iommu/iommufd/selftest.c | 30 +-
drivers/iommu/iova.c | 95 +-
drivers/iommu/ipmmu-vmsa.c | 72 +-
drivers/iommu/msm_iommu.c | 35 +-
drivers/iommu/mtk_iommu.c | 35 +-
drivers/iommu/mtk_iommu_v1.c | 28 +-
drivers/iommu/omap-iommu.c | 69 +-
drivers/iommu/omap-iommu.h | 2 +-
drivers/iommu/rockchip-iommu.c | 59 +-
drivers/iommu/s390-iommu.c | 424 ++++++++-
drivers/iommu/sprd-iommu.c | 36 +-
drivers/iommu/sun50i-iommu.c | 80 +-
drivers/iommu/tegra-gart.c | 371 --------
drivers/iommu/tegra-smmu.c | 58 +-
drivers/iommu/virtio-iommu.c | 4 +-
drivers/memory/tegra/mc.c | 34 -
drivers/memory/tegra/tegra20.c | 28 -
include/linux/amd-iommu.h | 120 ---
include/linux/iommu.h | 38 +-
include/soc/tegra/mc.h | 26 -
58 files changed, 2138 insertions(+), 3905 deletions(-)
delete mode 100644 arch/s390/pci/pci_dma.c
delete mode 100644 drivers/iommu/amd/iommu_v2.c
delete mode 100644 drivers/iommu/tegra-gart.c