Subject: Re: [PATCH 1/2] export cpu_tlbstate to modules

From: "H. Peter Anvin" <[email-masked]>
Date: Mon, 10 Aug 2009 14:56:46 -0700

On 08/10/2009 11:53 AM, Michael S. Tsirkin wrote:
> vhost net module wants to do copy to/from user from a kernel thread,
> which needs switch_mm (like what fs/aio has).
> export cpu_tlbstate to make this possible
> 
> Signed-off-by: Michael S. Tsirkin <[email-masked]>
> ---
>  arch/x86/mm/tlb.c |    1 +
>  1 files changed, 1 insertions(+), 0 deletions(-)
> 
> diff --git a/arch/x86/mm/tlb.c b/arch/x86/mm/tlb.c
> index 821e970..e33a5f0 100644
> --- a/arch/x86/mm/tlb.c
> +++ b/arch/x86/mm/tlb.c
> @@ -13,6 +13,7 @@
>  
>  DEFINE_PER_CPU_SHARED_ALIGNED(struct tlb_state, cpu_tlbstate)
>  			= { &init_mm, 0, };
> +EXPORT_PER_CPU_SYMBOL_GPL(cpu_tlbstate);
>  
>  /*
>   *	Smarter SMP flushing macros.

Wouldn't it be a *lot* better to move use_mm() from fs/aio.c into common
code, and export that instead?

	-hpa