Subject: Re: [PATCH] powerpc/mm/tlbflush: update the mmu_gather page size while iterating address range

From: Michael Ellerman <[email-masked]>
Date: Fri, 10 Aug 2018 17:09:29 +1000

"Aneesh Kumar K.V" <[email-masked]> writes:

> This patch makes sure we update the mmu_gather page size even if we are
> requesting for a fullmm flush. This avoids triggering VM_WARN_ON in code
> paths like __tlb_remove_page_size that explicitly check for removing range page
> size to be same as mmu gather page size.

I take it this is a fix for 5a6099346c41 ("powerpc/64s/radix: tlb do not flush on page size when fullmm") ?

cheers

> diff --git a/arch/powerpc/include/asm/tlb.h b/arch/powerpc/include/asm/tlb.h
> index 97ecef697e1b..f0e571b2dc7c 100644
> --- a/arch/powerpc/include/asm/tlb.h
> +++ b/arch/powerpc/include/asm/tlb.h
> @@ -49,13 +49,11 @@ static inline void __tlb_remove_tlb_entry(struct mmu_gather *tlb, pte_t *ptep,
>  static inline void tlb_remove_check_page_size_change(struct mmu_gather *tlb,
>  						     unsigned int page_size)
>  {
> -	if (tlb->fullmm)
> -		return;
> -
>  	if (!tlb->page_size)
>  		tlb->page_size = page_size;
>  	else if (tlb->page_size != page_size) {
> -		tlb_flush_mmu(tlb);
> +		if (!tlb->fullmm)
> +			tlb_flush_mmu(tlb);
>  		/*
>  		 * update the page size after flush for the new
>  		 * mmu_gather.
> -- 
> 2.17.1