If pcpu_map_pages() fails midway, it unmaps the already mapped pages.
Currently, it doesn't flush tlb after the partial unmapping.  This may
be okay in most cases as the established mapping hasn't been used at
that point but it can go wrong and when it goes wrong it'd be
extremely difficult to track down.

Flush tlb after the partial unmapping.

Signed-off-by: Tejun Heo <t...@kernel.org>
Cc: stable@vger.kernel.org
---
 mm/percpu-vm.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/mm/percpu-vm.c b/mm/percpu-vm.c
index 8d9bb2c..5110816 100644
--- a/mm/percpu-vm.c
+++ b/mm/percpu-vm.c
@@ -272,6 +272,7 @@ err:
                __pcpu_unmap_pages(pcpu_chunk_addr(chunk, tcpu, page_start),
                                   page_end - page_start);
        }
+       pcpu_post_unmap_tlb_flush(chunk, page_start, page_end);
        return err;
 }
 
-- 
1.9.3

--
To unsubscribe from this list: send the line "unsubscribe stable" in
the body of a message to majord...@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html

Reply via email to