On Fri, Jan 26, 2018 at 04:06:22PM +0800, Baoquan He wrote:
> Saw Huawei's bug report about kdump kernel hang when intel_iommu=off
> is set. I met the similar problem in amd system, only set amd_iommu=off
> in kdump kernel, it means amd_iommu is on in 1st kernel.
> I am reading doc and code, trying to debug. Please help have a look when
> convenient, see if there's hint or direction.
Yeah, I know that this is broken on the AMD-IOMMU side. Problem is that
the IOMMU hardware needs to be disabled in the kdump kernel when
amd_iommu=off is on the command-line. I'll look into fixing that.
I thought we fixed this a while ago already for VT-d, is it broken
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