powerpc/booke: Only check for hugetlb in flush if vma != NULL
And in flush_hugetlb_page(), don't check whether vma is NULL after
we've already dereferenced it.
This was found by Dan using static analysis as described here:
https://lists.ozlabs.org/pipermail/linuxppc-dev/2013-November/113161.html
We currently get away with this because the callers that currently pass
NULL for vma seem to be 32-bit-only (e.g. highmem, and
CONFIG_DEBUG_PGALLOC in pgtable_32.c) Hugetlb is currently 64-bit only,
so we never saw a NULL vma here.
Signed-off-by: Scott Wood <scottwood@freescale.com>
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
diff --git a/arch/powerpc/mm/hugetlbpage-book3e.c b/arch/powerpc/mm/hugetlbpage-book3e.c
index 3bc7006..74551b5 100644
--- a/arch/powerpc/mm/hugetlbpage-book3e.c
+++ b/arch/powerpc/mm/hugetlbpage-book3e.c
@@ -117,6 +117,5 @@
struct hstate *hstate = hstate_file(vma->vm_file);
unsigned long tsize = huge_page_shift(hstate) - 10;
- __flush_tlb_page(vma ? vma->vm_mm : NULL, vmaddr, tsize, 0);
-
+ __flush_tlb_page(vma->vm_mm, vmaddr, tsize, 0);
}
diff --git a/arch/powerpc/mm/tlb_nohash.c b/arch/powerpc/mm/tlb_nohash.c
index 41cd68d..358d743 100644
--- a/arch/powerpc/mm/tlb_nohash.c
+++ b/arch/powerpc/mm/tlb_nohash.c
@@ -305,7 +305,7 @@
void flush_tlb_page(struct vm_area_struct *vma, unsigned long vmaddr)
{
#ifdef CONFIG_HUGETLB_PAGE
- if (is_vm_hugetlb_page(vma))
+ if (vma && is_vm_hugetlb_page(vma))
flush_hugetlb_page(vma, vmaddr);
#endif