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 <[email protected]>
Tested-by: Gurudas Pai <[email protected]>
Signed-off-by: David S. Miller <[email protected]>
Acked-by: David Rientjes <[email protected]>
diff --git a/include/asm-generic/hugetlb.h b/include/asm-generic/hugetlb.h
index d06079c..99b490b 100644
--- a/include/asm-generic/hugetlb.h
+++ b/include/asm-generic/hugetlb.h
@@ -6,12 +6,12 @@
return mk_pte(page, pgprot);
}
-static inline int huge_pte_write(pte_t pte)
+static inline unsigned long huge_pte_write(pte_t pte)
{
return pte_write(pte);
}
-static inline int huge_pte_dirty(pte_t pte)
+static inline unsigned long huge_pte_dirty(pte_t pte)
{
return pte_dirty(pte);
}