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| author | Jason Low <jason.low2@hp.com> | 2015-04-15 16:14:05 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2015-04-15 16:35:18 -0700 |
| commit | 9d8c47e4bb1c20dbceee437f9fa7d76dafee80a2 (patch) | |
| tree | ce84c2d3b5f1cff2f1dc583f653f6c9d0f121a46 | |
| parent | 6cd576130b7152d8f225bab9d21a3f6f96c84b47 (diff) | |
| download | lwn-9d8c47e4bb1c20dbceee437f9fa7d76dafee80a2.tar.gz lwn-9d8c47e4bb1c20dbceee437f9fa7d76dafee80a2.zip | |
mm: use READ_ONCE() for non-scalar types
Commit 38c5ce936a08 ("mm/gup: Replace ACCESS_ONCE with READ_ONCE")
converted ACCESS_ONCE usage in gup_pmd_range() to READ_ONCE, since
ACCESS_ONCE doesn't work reliably on non-scalar types.
This patch also fixes the other ACCESS_ONCE usages in gup_pte_range()
and __get_user_pages_fast() in mm/gup.c
Signed-off-by: Jason Low <jason.low2@hp.com>
Acked-by: Michal Hocko <mhocko@suse.cz>
Acked-by: Davidlohr Bueso <dave@stgolabs.net>
Acked-by: Rik van Riel <riel@redhat.com>
Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
| -rw-r--r-- | mm/gup.c | 4 |
1 files changed, 2 insertions, 2 deletions
@@ -1019,7 +1019,7 @@ static int gup_pte_range(pmd_t pmd, unsigned long addr, unsigned long end, * * for an example see gup_get_pte in arch/x86/mm/gup.c */ - pte_t pte = ACCESS_ONCE(*ptep); + pte_t pte = READ_ONCE(*ptep); struct page *page; /* @@ -1309,7 +1309,7 @@ int __get_user_pages_fast(unsigned long start, int nr_pages, int write, local_irq_save(flags); pgdp = pgd_offset(mm, addr); do { - pgd_t pgd = ACCESS_ONCE(*pgdp); + pgd_t pgd = READ_ONCE(*pgdp); next = pgd_addr_end(addr, end); if (pgd_none(pgd)) |