Re: [RFC PATCH 2/2] mm: mmu_notifier fix for tlb_end_vma (build failures)

From: Guenter Roeck <linux@roeck-us.net>
To: Will Deacon <will.deacon@arm.com>
Cc: Nicholas Piggin <npiggin@gmail.com>,
	Peter Zijlstra <peterz@infradead.org>,
	torvalds@linux-foundation.org, luto@kernel.org, x86@kernel.org,
	bp@alien8.de, riel@surriel.com, jannh@google.com,
	ascannell@google.com, dave.hansen@intel.com,
	linux-kernel@vger.kernel.org, linux-mm@kvack.org,
	David Miller <davem@davemloft.net>,
	Martin Schwidefsky <schwidefsky@de.ibm.com>,
	Michael Ellerman <mpe@ellerman.id.au>,
	linux-arch@vger.kernel.org, Palmer Dabbelt <palmer@sifive.com>,
	linux-riscv@lists.infradead.org
Subject: Re: [RFC PATCH 2/2] mm: mmu_notifier fix for tlb_end_vma (build failures)
Date: Fri, 24 Aug 2018 11:22:59 -0700	[thread overview]
Message-ID: <20180824182259.GA18477@roeck-us.net> (raw)
In-Reply-To: <20180824142532.GG11868@brain-police>

On Fri, Aug 24, 2018 at 03:25:33PM +0100, Will Deacon wrote:
> On Fri, Aug 24, 2018 at 07:06:51AM -0700, Guenter Roeck wrote:
> > On 08/24/2018 06:50 AM, Will Deacon wrote:
> > 
> > >>-#include <asm-generic/tlb.h>
> > >>+struct mmu_gather;
> > >>  static inline void tlb_flush(struct mmu_gather *tlb)
> > >>  {
> > >>  	flush_tlb_mm(tlb->mm);
> > >
> > >Bah, didn't spot the dereference so this won't work either. You basically
> > >just need to copy what I did for arm64 in d475fac95779.
> > >
> > 
> > Yes, this seems to work. It doesn't really need "struct mmu_gather;" -
> > I assume that is included from elsewhere - but I added it to be safe.
> 
> struct mmu_gather comes in via asm-generic/tlb.h.
> 
From linux/mm.h, really, which happens to be included before
asm/tlb.h is included (see arch/riscv/include/asm/pgalloc.h).
I kept it to be future-proof.

> > Can you send a full patch, or do you want me to do it ?
> 
> I'm evidently incapable of writing code today, so please go ahead :)
> 
Done. We'll see if I am any better.

Guenter