Re: [PATCH] RISC-V: Move all address space definition macros to one place

[Atish Patra]

On Mon, Mar 23, 2020 at 3:32 AM David Abdurachmanov
<david.abdurachmanov@xxxxxxxxx> wrote:
>
> On Sat, Mar 21, 2020 at 10:29 PM David Abdurachmanov
> <david.abdurachmanov@xxxxxxxxx> wrote:
> >
> > On Fri, Mar 6, 2020 at 2:20 AM Palmer Dabbelt <palmerdabbelt@xxxxxxxxxx> wrote:
> > >
> > > On Mon, 24 Feb 2020 11:34:36 PST (-0800), Atish Patra wrote:
> > > > If both CONFIG_KASAN and CONFIG_SPARSEMEM_VMEMMAP are set, we get the
> > > > following compilation error.
> > > >
> > > > ---------------------------------------------------------------
> > > > ./arch/riscv/include/asm/pgtable-64.h: In function âpud_pageâ:
> > > > ./include/asm-generic/memory_model.h:54:29: error: âvmemmapâ undeclared
> > > > (first use in this function); did you mean âmem_mapâ?
> > > >  #define __pfn_to_page(pfn) (vmemmap + (pfn))
> > > >                              ^~~~~~~
> > > > ./include/asm-generic/memory_model.h:82:21: note: in expansion of
> > > > macro â__pfn_to_pageâ
> > > >
> > > >  #define pfn_to_page __pfn_to_page
> > > >                      ^~~~~~~~~~~~~
> > > > ./arch/riscv/include/asm/pgtable-64.h:70:9: note: in expansion of macro
> > > > âpfn_to_pageâ
> > > >   return pfn_to_page(pud_val(pud) >> _PAGE_PFN_SHIFT);
> > > > ---------------------------------------------------------------
> > > >
> > > > Fix the compliation errors by moving all the address space definition
> > > > macros before including pgtable-64.h.
> > > >
> > > > Cc: stable@xxxxxxxxxxxxxxx
> > > > Fixes: 8ad8b72721d0 (riscv: Add KASAN support)
> > > >
> > > > Signed-off-by: Atish Patra <atish.patra@xxxxxxx>
> > > > ---
> > > >  arch/riscv/include/asm/pgtable.h | 78 +++++++++++++++++---------------
> > > >  1 file changed, 41 insertions(+), 37 deletions(-)
> > > >
> > > > diff --git a/arch/riscv/include/asm/pgtable.h b/arch/riscv/include/asm/pgtable.h
> > > > index 453afb0a570a..4f6ee48a42e8 100644
> > > > --- a/arch/riscv/include/asm/pgtable.h
> > > > +++ b/arch/riscv/include/asm/pgtable.h
> > > > @@ -19,6 +19,47 @@
> > > >  #include <asm/tlbflush.h>
> > > >  #include <linux/mm_types.h>
> > > >
> > > > +#ifdef CONFIG_MMU
> > > > +
> > > > +#define VMALLOC_SIZE     (KERN_VIRT_SIZE >> 1)
> > > > +#define VMALLOC_END      (PAGE_OFFSET - 1)
> > > > +#define VMALLOC_START    (PAGE_OFFSET - VMALLOC_SIZE)
> > > > +
> > > > +#define BPF_JIT_REGION_SIZE  (SZ_128M)
> > > > +#define BPF_JIT_REGION_START (PAGE_OFFSET - BPF_JIT_REGION_SIZE)
> > > > +#define BPF_JIT_REGION_END   (VMALLOC_END)
> > > > +
> > > > +/*
> > > > + * Roughly size the vmemmap space to be large enough to fit enough
> > > > + * struct pages to map half the virtual address space. Then
> > > > + * position vmemmap directly below the VMALLOC region.
> > > > + */
> > > > +#define VMEMMAP_SHIFT \
> > > > +     (CONFIG_VA_BITS - PAGE_SHIFT - 1 + STRUCT_PAGE_MAX_SHIFT)
> > > > +#define VMEMMAP_SIZE BIT(VMEMMAP_SHIFT)
> > > > +#define VMEMMAP_END  (VMALLOC_START - 1)
> > > > +#define VMEMMAP_START        (VMALLOC_START - VMEMMAP_SIZE)
> > > > +
> > > > +/*
> > > > + * Define vmemmap for pfn_to_page & page_to_pfn calls. Needed if kernel
> > > > + * is configured with CONFIG_SPARSEMEM_VMEMMAP enabled.
> > > > + */
> > > > +#define vmemmap              ((struct page *)VMEMMAP_START)
> > > > +
> > > > +#define PCI_IO_SIZE      SZ_16M
> > > > +#define PCI_IO_END       VMEMMAP_START
> > > > +#define PCI_IO_START     (PCI_IO_END - PCI_IO_SIZE)
> > > > +
> > > > +#define FIXADDR_TOP      PCI_IO_START
> > > > +#ifdef CONFIG_64BIT
> > > > +#define FIXADDR_SIZE     PMD_SIZE
> > > > +#else
> > > > +#define FIXADDR_SIZE     PGDIR_SIZE
> > > > +#endif
> > > > +#define FIXADDR_START    (FIXADDR_TOP - FIXADDR_SIZE)
> > > > +
> > > > +#endif
> > > > +
> > > >  #ifdef CONFIG_64BIT
> > > >  #include <asm/pgtable-64.h>
> > > >  #else
> > > > @@ -90,31 +131,6 @@ extern pgd_t swapper_pg_dir[];
> > > >  #define __S110       PAGE_SHARED_EXEC
> > > >  #define __S111       PAGE_SHARED_EXEC
> > > >
> > > > -#define VMALLOC_SIZE     (KERN_VIRT_SIZE >> 1)
> > > > -#define VMALLOC_END      (PAGE_OFFSET - 1)
> > > > -#define VMALLOC_START    (PAGE_OFFSET - VMALLOC_SIZE)
> > > > -
> > > > -#define BPF_JIT_REGION_SIZE  (SZ_128M)
> > > > -#define BPF_JIT_REGION_START (PAGE_OFFSET - BPF_JIT_REGION_SIZE)
> > > > -#define BPF_JIT_REGION_END   (VMALLOC_END)
> > > > -
> > > > -/*
> > > > - * Roughly size the vmemmap space to be large enough to fit enough
> > > > - * struct pages to map half the virtual address space. Then
> > > > - * position vmemmap directly below the VMALLOC region.
> > > > - */
> > > > -#define VMEMMAP_SHIFT \
> > > > -     (CONFIG_VA_BITS - PAGE_SHIFT - 1 + STRUCT_PAGE_MAX_SHIFT)
> > > > -#define VMEMMAP_SIZE BIT(VMEMMAP_SHIFT)
> > > > -#define VMEMMAP_END  (VMALLOC_START - 1)
> > > > -#define VMEMMAP_START        (VMALLOC_START - VMEMMAP_SIZE)
> > > > -
> > > > -/*
> > > > - * Define vmemmap for pfn_to_page & page_to_pfn calls. Needed if kernel
> > > > - * is configured with CONFIG_SPARSEMEM_VMEMMAP enabled.
> > > > - */
> > > > -#define vmemmap              ((struct page *)VMEMMAP_START)
> > > > -
> > > >  static inline int pmd_present(pmd_t pmd)
> > > >  {
> > > >       return (pmd_val(pmd) & (_PAGE_PRESENT | _PAGE_PROT_NONE));
> > > > @@ -452,18 +468,6 @@ static inline int ptep_clear_flush_young(struct vm_area_struct *vma,
> > > >  #define __pte_to_swp_entry(pte)      ((swp_entry_t) { pte_val(pte) })
> > > >  #define __swp_entry_to_pte(x)        ((pte_t) { (x).val })
> > > >
> > > > -#define PCI_IO_SIZE      SZ_16M
> > > > -#define PCI_IO_END       VMEMMAP_START
> > > > -#define PCI_IO_START     (PCI_IO_END - PCI_IO_SIZE)
> > > > -
> > > > -#define FIXADDR_TOP      PCI_IO_START
> > > > -#ifdef CONFIG_64BIT
> > > > -#define FIXADDR_SIZE     PMD_SIZE
> > > > -#else
> > > > -#define FIXADDR_SIZE     PGDIR_SIZE
> > > > -#endif
> > > > -#define FIXADDR_START    (FIXADDR_TOP - FIXADDR_SIZE)
> > > > -
> > > >  /*
> > > >   * Task size is 0x4000000000 for RV64 or 0x9fc00000 for RV32.
> > > >   * Note that PGDIR_SIZE must evenly divide TASK_SIZE.
> > >
> > > While this isn't technically a fix, I'm inclined to target it for the RCs just
> > > to avoid conflicts.  I've put it on for-next now so the builders have some time
> > > to chew on things, as I don't want to put in a non-fix too quickly.
> >
> > I hit the same issue in Fedora/RISCV while building kernel-5.6.0-0.rc6, and
> > we don't have KASAN selected. We do have CONFIG_SPARSEMEM_VMEMMAP
> > selected.
> >

Yes. I just verified that. CONFIG_SPARSEMEM_VMEMMAP is enough to
trigger the build error.
The code that raises the compilation error is added by kasan patchset,
but it is not dependent upon kasan.

--- a/arch/riscv/include/asm/pgtable-64.h
+++ b/arch/riscv/include/asm/pgtable-64.h
@@ -58,6 +58,11 @@ static inline unsigned long pud_page_vaddr(pud_t pud)
        return (unsigned long)pfn_to_virt(pud_val(pud) >> _PAGE_PFN_SHIFT);
 }

+static inline struct page *pud_page(pud_t pud)
+{
+       return pfn_to_page(pud_val(pud) >> _PAGE_PFN_SHIFT);
+}
+

@palmer: I am not sure if it is too late for an RC-fix. If not, can
you send it as an RC-fix ?

Let me know if you want me to respin the patch editing the commit text.

> > I will try this patch tomorrow.
> >
> Confirmed to solve my build errors with kernel in Fedora/RISCV.
>
> david
>


-- 
Regards,
Atish