Re: [PATCH v3 1/8] mm: Cleanup faultaround and finish_fault() codepaths

[Will Deacon <will@kernel.org>]

On Tue, Feb 09, 2021 at 12:24:49PM -0800, Guenter Roeck wrote:
> On Thu, Jan 14, 2021 at 05:59:27PM +0000, Will Deacon wrote:
> > From: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
> > 
> > alloc_set_pte() has two users with different requirements: in the
> > faultaround code, it called from an atomic context and PTE page table
> > has to be preallocated. finish_fault() can sleep and allocate page table
> > as needed.
> > 
> > PTL locking rules are also strange, hard to follow and overkill for
> > finish_fault().
> > 
> > Let's untangle the mess. alloc_set_pte() has gone now. All locking is
> > explicit.
> > 
> > The price is some code duplication to handle huge pages in faultaround
> > path, but it should be fine, having overall improvement in readability.
> > 
> > Link: https://lore.kernel.org/r/20201229132819.najtavneutnf7ajp@box
> > Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
> > [will: s/from from/from/ in comment; spotted by willy]
> > Signed-off-by: Will Deacon <will@kernel.org>
> > ---
> >  fs/xfs/xfs_file.c       |   6 +-
> >  include/linux/mm.h      |  12 ++-
> >  include/linux/pgtable.h |  11 +++
> >  mm/filemap.c            | 177 ++++++++++++++++++++++++++---------
> >  mm/memory.c             | 199 ++++++++++++----------------------------
> >  5 files changed, 213 insertions(+), 192 deletions(-)
> > 
> 
> When building microblaze:mmu_defconfig:
> 
> mm/filemap.c: In function 'filemap_map_pages':
> mm/filemap.c:3153:3: error: implicit declaration of function 'update_mmu_cache'; did you mean 'update_mmu_tlb'?
> 
> Bisect log attached.

Looks like a missing include.

Will

--->8

From 076f93117c067d5b6caab4773c6d6da130859cc4 Mon Sep 17 00:00:00 2001
From: Will Deacon <will@kernel.org>
Date: Wed, 10 Feb 2021 11:15:11 +0000
Subject: [PATCH] mm: filemap: Fix microblaze build failure with
 'mmu_defconfig'

Commit f9ce0be71d1f ("mm: Cleanup faultaround and finish_fault()
codepaths") added a call to 'update_mmu_cache()' in mm/filemap.c, which
breaks the build for microblaze:

  | mm/filemap.c: In function 'filemap_map_pages':
  | mm/filemap.c:3153:3: error: implicit declaration of function 'update_mmu_cache'; did you mean 'update_mmu_tlb'?

Include asm/tlbflush.h in mm/filemap.c to make sure that the function
(or indeed, macro) is available.

Reported-by: Guenter Roeck <linux@roeck-us.net>
Link: https://lore.kernel.org/r/20210209202449.GA104837@roeck-us.net
Signed-off-by: Will Deacon <will@kernel.org>
---
 mm/filemap.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/mm/filemap.c b/mm/filemap.c
index fb7a8d9b5603..2ca13227747b 100644
--- a/mm/filemap.c
+++ b/mm/filemap.c
@@ -43,6 +43,7 @@
 #include <linux/ramfs.h>
 #include <linux/page_idle.h>
 #include <asm/pgalloc.h>
+#include <asm/tlbflush.h>
 #include "internal.h"
 
 #define CREATE_TRACE_POINTS
-- 
2.30.0.478.g8a0d178c01-goog