diff options
author | Leonid Yegoshin <Leonid.Yegoshin@imgtec.com> | 2013-05-24 15:55:18 -0700 |
---|---|---|
committer | Ben Hutchings <ben@decadent.org.uk> | 2013-05-30 14:35:06 +0100 |
commit | 7fa32acca588177bbc49dc2b4c6fa469c4aa5bd5 (patch) | |
tree | c08f151d708dea0095900704df3bcac0c8d3ae4b /mm | |
parent | 1619f441963ea57fa1082d046da867acfcd4d099 (diff) |
mm compaction: fix of improper cache flush in migration code
commit c2cc499c5bcf9040a738f49e8051b42078205748 upstream.
Page 'new' during MIGRATION can't be flushed with flush_cache_page().
Using flush_cache_page(vma, addr, pfn) is justified only if the page is
already placed in process page table, and that is done right after
flush_cache_page(). But without it the arch function has no knowledge
of process PTE and does nothing.
Besides that, flush_cache_page() flushes an application cache page, but
the kernel has a different page virtual address and dirtied it.
Replace it with flush_dcache_page(new) which is the proper usage.
The old page is flushed in try_to_unmap_one() before migration.
This bug takes place in Sead3 board with M14Kc MIPS CPU without cache
aliasing (but Harvard arch - separate I and D cache) in tight memory
environment (128MB) each 1-3days on SOAK test. It fails in cc1 during
kernel build (SIGILL, SIGBUS, SIGSEG) if CONFIG_COMPACTION is switched
ON.
Signed-off-by: Leonid Yegoshin <Leonid.Yegoshin@imgtec.com>
Cc: Leonid Yegoshin <yegoshin@mips.com>
Acked-by: Rik van Riel <riel@redhat.com>
Cc: Michal Hocko <mhocko@suse.cz>
Acked-by: Mel Gorman <mgorman@suse.de>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Russell King <rmk@arm.linux.org.uk>
Cc: David Miller <davem@davemloft.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Diffstat (limited to 'mm')
-rw-r--r-- | mm/migrate.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/mm/migrate.c b/mm/migrate.c index 180d97fe86c..e1052d15a14 100644 --- a/mm/migrate.c +++ b/mm/migrate.c @@ -147,7 +147,7 @@ static int remove_migration_pte(struct page *new, struct vm_area_struct *vma, if (PageHuge(new)) pte = pte_mkhuge(pte); #endif - flush_cache_page(vma, addr, pte_pfn(pte)); + flush_dcache_page(new); set_pte_at(mm, addr, ptep, pte); if (PageHuge(new)) { |