Re: [PATCH] parisc: fix PMD pages allocation by restoring pmd_alloc_one()

[Mike Rapoport <rppt@kernel.org>]

On Sun, Aug 16, 2020 at 03:42:09PM +0100, Matthew Wilcox wrote:
> On Sun, Aug 16, 2020 at 05:24:03PM +0300, Mike Rapoport wrote:
> > From: Mike Rapoport <rppt@linux.ibm.com>
> > 
> > Commit 1355c31eeb7e ("asm-generic: pgalloc: provide generic pmd_alloc_one()
> > and pmd_free_one()") converted parisc to use generic version of
> > pmd_alloc_one() but it missed the fact that parisc uses order-1 pages for
> > PMD.
> > 
> > Restore the original version of pmd_alloc_one() for parisc, just use
> > GFP_PGTABLE_KERNEL that implies __GFP_ZERO instead of GFP_KERNEL and
> > memset.
> > 
> > Fixes: 1355c31eeb7e ("asm-generic: pgalloc: provide generic pmd_alloc_one() and pmd_free_one()")
> > Repoerted-by: Meelis Roos <mroos@linux.ee>
> 
> typo, "Reported-by"

Helge,

I presume this is going via parisc tree, do you mind fixing up
while applying?

> Reviewed-by: Matthew Wilcox (Oracle) <willy@infradead.org>
> 
> > Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
> > Tested-by: Meelis Roos <mroos@linux.ee>
> > Link: https://lkml.kernel.org/r/9f2b5ebd-e4a4-0fa1-6cd3-4b9f6892d1ad@linux.ee 
> > ---
> > 
> > Hi,
> > 
> > I've trimmed the 'cc list relatively to the bug report and added parisc
> > maintainers.
> > 
> >  arch/parisc/include/asm/pgalloc.h | 6 ++++++
> >  1 file changed, 6 insertions(+)
> > 
> > diff --git a/arch/parisc/include/asm/pgalloc.h b/arch/parisc/include/asm/pgalloc.h
> > index cc7ecc2ef55d..a6482b2ce0ea 100644
> > --- a/arch/parisc/include/asm/pgalloc.h
> > +++ b/arch/parisc/include/asm/pgalloc.h
> > @@ -10,6 +10,7 @@
> >  
> >  #include <asm/cache.h>
> >  
> > +#define __HAVE_ARCH_PMD_ALLOC_ONE
> >  #define __HAVE_ARCH_PMD_FREE
> >  #define __HAVE_ARCH_PGD_FREE
> >  #include <asm-generic/pgalloc.h>
> > @@ -67,6 +68,11 @@ static inline void pud_populate(struct mm_struct *mm, pud_t *pud, pmd_t *pmd)
> >  			(__u32)(__pa((unsigned long)pmd) >> PxD_VALUE_SHIFT)));
> >  }
> >  
> > +static inline pmd_t *pmd_alloc_one(struct mm_struct *mm, unsigned long address)
> > +{
> > +	return (pmd_t *)__get_free_pages(GFP_PGTABLE_KERNEL, PMD_ORDER);
> > +}
> > +
> >  static inline void pmd_free(struct mm_struct *mm, pmd_t *pmd)
> >  {
> >  	if (pmd_flag(*pmd) & PxD_FLAG_ATTACHED) {
> > -- 
> > 2.26.2
> > 

-- 
Sincerely yours,
Mike.