linux-hardened/include/asm-generic/hugetlb.h
David Miller 2679494246 mm: Fix generic hugetlb pte check return type.
The include/asm-generic/hugetlb.h stubs that just vector huge_pte_*()
calls to the pte_*() implementations won't work in certain situations.

x86 and sparc, for example, return "unsigned long" from the bit
checks, and just go "return pte_val(pte) & PTE_BIT_FOO;"

But since huge_pte_*() returns 'int', if any high bits on 64-bit are
relevant, they get chopped off.

The net effect is that we can loop forever trying to COW a huge page,
because the huge_pte_write() check signals false all the time.

Reported-by: Gurudas Pai <gurudas.pai@oracle.com>
Tested-by: Gurudas Pai <gurudas.pai@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Acked-by: David Rientjes <rientjes@google.com>
2013-10-02 20:02:35 -04:00

40 lines
758 B
C

#ifndef _ASM_GENERIC_HUGETLB_H
#define _ASM_GENERIC_HUGETLB_H
static inline pte_t mk_huge_pte(struct page *page, pgprot_t pgprot)
{
return mk_pte(page, pgprot);
}
static inline unsigned long huge_pte_write(pte_t pte)
{
return pte_write(pte);
}
static inline unsigned long huge_pte_dirty(pte_t pte)
{
return pte_dirty(pte);
}
static inline pte_t huge_pte_mkwrite(pte_t pte)
{
return pte_mkwrite(pte);
}
static inline pte_t huge_pte_mkdirty(pte_t pte)
{
return pte_mkdirty(pte);
}
static inline pte_t huge_pte_modify(pte_t pte, pgprot_t newprot)
{
return pte_modify(pte, newprot);
}
static inline void huge_pte_clear(struct mm_struct *mm, unsigned long addr,
pte_t *ptep)
{
pte_clear(mm, addr, ptep);
}
#endif /* _ASM_GENERIC_HUGETLB_H */