[PATCH -fixes v2] riscv: Fix missing PAGE_PFN_MASK

[Anup Patel]

Hi Palmer,

On Mon, Jun 13, 2022 at 3:01 PM Anup Patel <anup at brainfault.org> wrote:
>
> On Mon, Jun 13, 2022 at 2:23 PM Alexandre Ghiti
> <alexandre.ghiti at canonical.com> wrote:
> >
> > There are a bunch of functions that use the PFN from a page table entry
> > that end up with the svpbmt upper-bits because they are missing the newly
> > introduced PAGE_PFN_MASK which leads to wrong addresses conversions and
> > then crash: fix this by adding this mask.
> >
> > Fixes: 100631b48ded ("riscv: Fix accessing pfn bits in PTEs for non-32bit variants")
> > Signed-off-by: Alexandre Ghiti <alexandre.ghiti at canonical.com>
>
> Looks good to me.
>
> Reviewed-by: Anup Patel <anup at brainfault.org>
>
> @Palmer let me know if you want me to take this through the KVM repo.

This patch is required for KVM Svpbmt support so I have included it
in my KVM RISC-V Svpbmt series.

Let me know if you plan to send this as fix for Linux-5.19-rcX

Regards,
Anup

>
> Regards,
> Anup
>
> > ---
> >  arch/riscv/include/asm/pgtable-64.h | 12 ++++++------
> >  arch/riscv/include/asm/pgtable.h    |  6 +++---
> >  arch/riscv/kvm/mmu.c                |  2 +-
> >  3 files changed, 10 insertions(+), 10 deletions(-)
> >
> > diff --git a/arch/riscv/include/asm/pgtable-64.h b/arch/riscv/include/asm/pgtable-64.h
> > index 5c2aba5efbd0..dc42375c2357 100644
> > --- a/arch/riscv/include/asm/pgtable-64.h
> > +++ b/arch/riscv/include/asm/pgtable-64.h
> > @@ -175,7 +175,7 @@ static inline pud_t pfn_pud(unsigned long pfn, pgprot_t prot)
> >
> >  static inline unsigned long _pud_pfn(pud_t pud)
> >  {
> > -       return pud_val(pud) >> _PAGE_PFN_SHIFT;
> > +       return __page_val_to_pfn(pud_val(pud));
> >  }
> >
> >  static inline pmd_t *pud_pgtable(pud_t pud)
> > @@ -278,13 +278,13 @@ static inline p4d_t pfn_p4d(unsigned long pfn, pgprot_t prot)
> >
> >  static inline unsigned long _p4d_pfn(p4d_t p4d)
> >  {
> > -       return p4d_val(p4d) >> _PAGE_PFN_SHIFT;
> > +       return __page_val_to_pfn(p4d_val(p4d));
> >  }
> >
> >  static inline pud_t *p4d_pgtable(p4d_t p4d)
> >  {
> >         if (pgtable_l4_enabled)
> > -               return (pud_t *)pfn_to_virt(p4d_val(p4d) >> _PAGE_PFN_SHIFT);
> > +               return (pud_t *)pfn_to_virt(__page_val_to_pfn(p4d_val(p4d)));
> >
> >         return (pud_t *)pud_pgtable((pud_t) { p4d_val(p4d) });
> >  }
> > @@ -292,7 +292,7 @@ static inline pud_t *p4d_pgtable(p4d_t p4d)
> >
> >  static inline struct page *p4d_page(p4d_t p4d)
> >  {
> > -       return pfn_to_page(p4d_val(p4d) >> _PAGE_PFN_SHIFT);
> > +       return pfn_to_page(__page_val_to_pfn(p4d_val(p4d)));
> >  }
> >
> >  #define pud_index(addr) (((addr) >> PUD_SHIFT) & (PTRS_PER_PUD - 1))
> > @@ -347,7 +347,7 @@ static inline void pgd_clear(pgd_t *pgd)
> >  static inline p4d_t *pgd_pgtable(pgd_t pgd)
> >  {
> >         if (pgtable_l5_enabled)
> > -               return (p4d_t *)pfn_to_virt(pgd_val(pgd) >> _PAGE_PFN_SHIFT);
> > +               return (p4d_t *)pfn_to_virt(__page_val_to_pfn(pgd_val(pgd)));
> >
> >         return (p4d_t *)p4d_pgtable((p4d_t) { pgd_val(pgd) });
> >  }
> > @@ -355,7 +355,7 @@ static inline p4d_t *pgd_pgtable(pgd_t pgd)
> >
> >  static inline struct page *pgd_page(pgd_t pgd)
> >  {
> > -       return pfn_to_page(pgd_val(pgd) >> _PAGE_PFN_SHIFT);
> > +       return pfn_to_page(__page_val_to_pfn(pgd_val(pgd)));
> >  }
> >  #define pgd_page(pgd)  pgd_page(pgd)
> >
> > diff --git a/arch/riscv/include/asm/pgtable.h b/arch/riscv/include/asm/pgtable.h
> > index 1d1be9d9419c..5dbd6610729b 100644
> > --- a/arch/riscv/include/asm/pgtable.h
> > +++ b/arch/riscv/include/asm/pgtable.h
> > @@ -261,7 +261,7 @@ static inline pgd_t pfn_pgd(unsigned long pfn, pgprot_t prot)
> >
> >  static inline unsigned long _pgd_pfn(pgd_t pgd)
> >  {
> > -       return pgd_val(pgd) >> _PAGE_PFN_SHIFT;
> > +       return __page_val_to_pfn(pgd_val(pgd));
> >  }
> >
> >  static inline struct page *pmd_page(pmd_t pmd)
> > @@ -590,14 +590,14 @@ static inline pmd_t pmd_mkinvalid(pmd_t pmd)
> >         return __pmd(pmd_val(pmd) & ~(_PAGE_PRESENT|_PAGE_PROT_NONE));
> >  }
> >
> > -#define __pmd_to_phys(pmd)  (pmd_val(pmd) >> _PAGE_PFN_SHIFT << PAGE_SHIFT)
> > +#define __pmd_to_phys(pmd)  (__page_val_to_pfn(pmd_val(pmd)) << PAGE_SHIFT)
> >
> >  static inline unsigned long pmd_pfn(pmd_t pmd)
> >  {
> >         return ((__pmd_to_phys(pmd) & PMD_MASK) >> PAGE_SHIFT);
> >  }
> >
> > -#define __pud_to_phys(pud)  (pud_val(pud) >> _PAGE_PFN_SHIFT << PAGE_SHIFT)
> > +#define __pud_to_phys(pud)  (__page_val_to_pfn(pud_val(pud)) << PAGE_SHIFT)
> >
> >  static inline unsigned long pud_pfn(pud_t pud)
> >  {
> > diff --git a/arch/riscv/kvm/mmu.c b/arch/riscv/kvm/mmu.c
> > index 1c00695ebee7..9826073fbc67 100644
> > --- a/arch/riscv/kvm/mmu.c
> > +++ b/arch/riscv/kvm/mmu.c
> > @@ -54,7 +54,7 @@ static inline unsigned long gstage_pte_index(gpa_t addr, u32 level)
> >
> >  static inline unsigned long gstage_pte_page_vaddr(pte_t pte)
> >  {
> > -       return (unsigned long)pfn_to_virt(pte_val(pte) >> _PAGE_PFN_SHIFT);
> > +       return (unsigned long)pfn_to_virt(__page_val_to_pfn(pte_val(pte)));
> >  }
> >
> >  static int gstage_page_size_to_level(unsigned long page_size, u32 *out_level)
> > --
> > 2.34.1
> >