Am 02.06.2022 17:27, schrieb Ben Hutchings:
On Thu, 2022-06-02 at 15:42 +0200, Markus Kolb wrote:
[...]
there is introduced the kernel config option
INTEL_IOMMU_DEFAULT_ON_INTGPU_OFF
but it is not handled anywhere in the code.
It is handled implicitly. When that config symbol is enabled, both
INTEL_IOMMU_DEFAULT_ON and INTEL_IOMMU_DEFAULT_OFF are disabled.
[...]
No, the whole point of INTEL_IOMMU_DEFAULT_ON_INTGPU_OFF is to turn
that off by default while still enabling the IOMMU for other devices.
Yes, I got this, but not sure if the code logic is really correct.
With this INTEL_IOMMU_DEFAULT_ON is "implicitly" falsy and the code is
supposed to run like it would be truthy.
Based on the log from your self-built kernel, it seems like your system
should work with the kernel parameter "intel_iommu=on". Can you test
whether that makes a difference with the Debian kernels?
With Debian kernel it doesn't boot with
intel_iommu=on
and also not with
intel_iommu=on,intgpu_off (which should be the same like nothing
specified).
Really only possibility intel_iommu=on,igfx_off.
