hugetlb: handle write-protection faults in follow_hugetlb_page
authorAdam Litke <agl@us.ibm.com>
Mon, 10 Dec 2007 23:49:28 +0000 (15:49 -0800)
committerLinus Torvalds <torvalds@woody.linux-foundation.org>
Tue, 11 Dec 2007 03:43:55 +0000 (19:43 -0800)
commit72fad7139b6829f71d7f41f39eb30da5760d90a8
tree4f33b824f37923b8f65f2a0542a2e9dcb110c22e
parent8805f2387086a7e6a9647d0713fc075694130d6c
hugetlb: handle write-protection faults in follow_hugetlb_page

The follow_hugetlb_page() fix I posted (merged as git commit
5b23dbe8173c212d6a326e35347b038705603d39) missed one case.  If the pte is
present, but not writable and write access is requested by the caller to
get_user_pages(), the code will do the wrong thing.  Rather than calling
hugetlb_fault to make the pte writable, it notes the presence of the pte
and continues.

This simple one-liner makes sure we also fault on the pte for this case.
Please apply.

Signed-off-by: Adam Litke <agl@us.ibm.com>
Acked-by: Dave Kleikamp <shaggy@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
mm/hugetlb.c