Re: linux-next: build failure after merge of the tip tree

[Mikko Perttunen]

On 05.04.2017 06:36, Stephen Rothwell wrote:
> Hi all,
>
> After merging the tip tree, today's linux-next build (arm
> multi_v7_defconfig) failed like this:
>
> drivers/gpu/built-in.o:(__tracepoints+0x64): multiple definition of `__tracepoint_remove_device_from_group'
> drivers/iommu/built-in.o:(__tracepoints+0x64): first defined here
> drivers/gpu/built-in.o:(__tracepoints+0x3c): multiple definition of `__tracepoint_detach_device_from_domain'
> drivers/iommu/built-in.o:(__tracepoints+0x3c): first defined here
> drivers/gpu/built-in.o:(__tracepoints+0x0): multiple definition of `__tracepoint_io_page_fault'
> drivers/iommu/built-in.o:(__tracepoints+0x0): first defined here
> drivers/gpu/built-in.o:(__tracepoints+0x78): multiple definition of `__tracepoint_add_device_to_group'
> drivers/iommu/built-in.o:(__tracepoints+0x78): first defined here
> drivers/gpu/built-in.o:(__tracepoints+0x14): multiple definition of `__tracepoint_unmap'
> drivers/iommu/built-in.o:(__tracepoints+0x14): first defined here
> drivers/gpu/built-in.o:(__tracepoints+0x28): multiple definition of `__tracepoint_map'
> drivers/iommu/built-in.o:(__tracepoints+0x28): first defined here
> drivers/gpu/built-in.o:(__tracepoints+0x50): multiple definition of `__tracepoint_attach_device_to_domain'
> drivers/iommu/built-in.o:(__tracepoints+0x50): first defined here
>
> The tip tree has not changed since yesterday.  However, reverting
> the drm-tegra tree fixes the build problem.  So there is some interaction
> between the tip tree and today's drm-tegra tree.
>
> So for now, I have reverted the merge of the drm-tegra tree.

Looks like this is caused by my patch to add IOMMU support to Host1x. 
I'm confused by how it doesn't appear on ARMv8, though. The cause is 
that host1x/dev.c defines CREATE_TRACE_POINTS and includes 
trace/events/host1x.h, which is fine. However, it then also includes, 
among other local files, dev.h. This used to be fine, but my patch adds 
an include of linux/iommu.h to dev.h, so we get this failure. I'll post 
a fix shortly.

Thanks,
Mikko.