Patchwork [v2,5/7] mm: Add and use update_mmu_cache_pmd() in transparent huge page code.

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Submitter Andrew Morton
Date Oct. 5, 2012, 10:01 p.m.
Message ID <20121005150110.fdf08c96.akpm@linux-foundation.org>
Download mbox | patch
Permalink /patch/189609/
State Not Applicable
Delegated to: David Miller
Headers show

Comments

Andrew Morton - Oct. 5, 2012, 10:01 p.m.
On Thu, 04 Oct 2012 15:47:38 -0400 (EDT)
David Miller <davem@davemloft.net> wrote:

> The transparent huge page code passes a PMD pointer in as the third
> argument of update_mmu_cache(), which expects a PTE pointer.
> 
> This never got noticed because X86 implements update_mmu_cache() as a
> macro and thus we don't get any type checking, and X86 is the only
> architecture which supports transparent huge pages currently.
> 
> Before oter architectures can support transparent huge pages properly
> we need to add a new interface which will take a PMD pointer as the
> third argument rather than a PTE pointer.

I'll toss this on top:

Patch

--- a/arch/s390/include/asm/pgtable.h~mm-add-and-use-update_mmu_cache_pmd-in-transparent-huge-page-code-fix
+++ a/arch/s390/include/asm/pgtable.h
@@ -42,6 +42,7 @@  extern void fault_init(void);
  * tables contain all the necessary information.
  */
 #define update_mmu_cache(vma, address, ptep)     do { } while (0)
+#define update_mmu_cache_pmd(vma, address, ptep) do { } while (0)
 
 /*
  * ZERO_PAGE is a global shared page that is always zero; used