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| author | Vineet Gupta <vgupta@synopsys.com> | 2016-05-05 14:53:48 +0530 |
|---|---|---|
| committer | Vineet Gupta <vgupta@synopsys.com> | 2016-05-05 16:35:45 +0530 |
| commit | 2519d753676bdf2460fbbcde276d5b6ba8d6b695 (patch) | |
| tree | 4db307eac2f8efbfe9699b6c0bb449d346d6ad10 /arch/arc | |
| parent | e5bc0478ab6cf565619224536d75ecb2aedca43b (diff) | |
| download | linux-2519d753676bdf2460fbbcde276d5b6ba8d6b695.tar.bz2 | |
ARC: Fix PAE40 boot failures due to PTE truncation
So a benign looking cleanup which macro'ized PAGE_SHIFT shifts turned
out to be bad (since it was done non-sensically across the board).
It caused boot failures with PAE40 as forced cast to (unsigned long)
from newly introduced virt_to_pfn() was causing truncatiion of the
(long long) pte/paddr values.
It is OK to use this in accessors dealing with kernel virtual address,
pointers etc, but not for PTE values themelves.
Fixes: cJ2ff5cf2735c ("ARC: mm: Use virt_to_pfn() for addr >> PAGE_SHIFT pattern)
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Diffstat (limited to 'arch/arc')
| -rw-r--r-- | arch/arc/include/asm/page.h | 9 | ||||
| -rw-r--r-- | arch/arc/include/asm/pgtable.h | 13 |
2 files changed, 14 insertions, 8 deletions
diff --git a/arch/arc/include/asm/page.h b/arch/arc/include/asm/page.h index 36da89e2c853..533e5a0c6ba5 100644 --- a/arch/arc/include/asm/page.h +++ b/arch/arc/include/asm/page.h @@ -72,6 +72,13 @@ typedef unsigned long pgprot_t; typedef pte_t * pgtable_t; +/* + * Use virt_to_pfn with caution: + * If used in pte or paddr related macros, it could cause truncation + * in PAE40 builds + * As a rule of thumb, only use it in helpers starting with virt_ + * You have been warned ! + */ #define virt_to_pfn(kaddr) (__pa(kaddr) >> PAGE_SHIFT) #define ARCH_PFN_OFFSET virt_to_pfn(CONFIG_LINUX_LINK_BASE) @@ -85,7 +92,7 @@ typedef pte_t * pgtable_t; * virt here means link-address/program-address as embedded in object code. * And for ARC, link-addr = physical address */ -#define __pa(vaddr) ((unsigned long)vaddr) +#define __pa(vaddr) ((unsigned long)(vaddr)) #define __va(paddr) ((void *)((unsigned long)(paddr))) #define virt_to_page(kaddr) \ diff --git a/arch/arc/include/asm/pgtable.h b/arch/arc/include/asm/pgtable.h index 7d6c93e63adf..10d4b8b8e545 100644 --- a/arch/arc/include/asm/pgtable.h +++ b/arch/arc/include/asm/pgtable.h @@ -278,14 +278,13 @@ static inline void pmd_set(pmd_t *pmdp, pte_t *ptep) #define pmd_present(x) (pmd_val(x)) #define pmd_clear(xp) do { pmd_val(*(xp)) = 0; } while (0) -#define pte_page(pte) \ - (mem_map + virt_to_pfn(pte_val(pte) - CONFIG_LINUX_LINK_BASE)) - +#define pte_page(pte) pfn_to_page(pte_pfn(pte)) #define mk_pte(page, prot) pfn_pte(page_to_pfn(page), prot) -#define pte_pfn(pte) virt_to_pfn(pte_val(pte)) -#define pfn_pte(pfn, prot) (__pte(((pte_t)(pfn) << PAGE_SHIFT) | \ - pgprot_val(prot))) -#define __pte_index(addr) (virt_to_pfn(addr) & (PTRS_PER_PTE - 1)) +#define pfn_pte(pfn, prot) (__pte(((pte_t)(pfn) << PAGE_SHIFT) | pgprot_val(prot))) + +/* Don't use virt_to_pfn for macros below: could cause truncations for PAE40*/ +#define pte_pfn(pte) (pte_val(pte) >> PAGE_SHIFT) +#define __pte_index(addr) (((addr) >> PAGE_SHIFT) & (PTRS_PER_PTE - 1)) /* * pte_offset gets a @ptr to PMD entry (PGD in our 2-tier paging system) |