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Date:   Fri, 10 Apr 2020 14:13:20 -0300
From:   Jason Gunthorpe <jgg@ziepe.ca>
To:     Saeed Mahameed <saeedm@mellanox.com>
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Subject: Re: [RFC 0/6] Regressions for "imply" behavior change
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On Fri, Apr 10, 2020 at 02:40:42AM +0000, Saeed Mahameed wrote:

> This assumes that the module using FOO has its own flag representing
> FOO which is not always the case.
> 
> for example in mlx5 we use VXLAN config flag directly to compile VXLAN
> related files:
> 
> mlx5/core/Makefile:
> 
> obj-$(CONFIG_MLX5_CORE) += mlx5_core.o
> 
> mlx5_core-y := mlx5_core.o
> mlx5_core-$(VXLAN) += mlx5_vxlan.o
> 
> and in mlx5_main.o we do:

Does this work if VXLAN = m ?

> if (IS_ENABLED(VXLAN))
>        mlx5_vxlan_init()
> 
> after the change in imply semantics:
> our options are:
> 
> 1) use IS_REACHABLE(VXLAN) instead of IS_ENABLED(VXLAN)
> 
> 2) have MLX5_VXLAN in mlx5 Kconfig and use IS_ENABLED(MLX5_VXLAN) 
> config MLX5_VXLAN
> 	depends on VXLAN || !VXLAN
> 	bool

Does this trick work when vxlan is a bool not a tristate?

Why not just put the VXLAN || !VXLAN directly on MLX5_CORE?

Jason