Re: [PATCH v3 02/11] x86/ldt: Simplify LDT switching logic

[Thomas Gleixner]

On Tue, 20 Jun 2017, Andy Lutomirski wrote:
> When we redo lazy mode to stop flush IPIs without switching to
> init_mm, though, the current logic would become incorrect: it will
> be possible to have real_prev == next but nonetheless have a stale
> LDT descriptor.
> 
> Simplify the code to update LDTR if either the previous or the next
> mm has an LDT, i.e. effectively restore the historical logic..
> While we're at it, clean up the code by moving all the ifdeffery to
> a header where it belongs.
> 
> Acked-by: Rik van Riel <riel@xxxxxxxxxx>
> Signed-off-by: Andy Lutomirski <luto@xxxxxxxxxx>

Reviewed-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>