Re: [tip:x86/platform] x86/intel/quark: Switch off CR4.PGE so TLB flush uses CR3 instead

Bryan O'Donoghue
2014-09-24T15:58:18Z

>
> I believe there is one more change needed: there is a __flush_tlb_all()
> in the early code which gets executed before the above code runs; the
> easiest fix is to just add a __flush_tlb() immediately after it.
>
> This should have been pushed upstream, and not stayed in the BSP kernel.

Peter.

You're talking about void __init setup_arch() right ?

The code looks like this

load_cr3(swapper_pg_dir);
__flush_tlb_all();

Note that on Quark the method to invalidate the TLB is by reloading CR3
- which is immediately prior to __flush_tlb_all();

So __flush_tlb_all(); will do nothing but that's OK since load_cr3()
already flushed the TLB - including any PTE with PGE set

Best,
Bryan