3.6.11.6 stable review patch. If anyone has any objections, please let me know. ------------------ From: Brian Behlendorf [ Upstream commit dfd20b2b174d3a9b258ea3b7a35ead33576587b1 ] The index on the page must be set before it is inserted in the radix tree. Otherwise there is a small race which can occur during lookup where the page can be found with the incorrect index. This will trigger the BUG_ON() in brd_lookup_page(). Signed-off-by: Brian Behlendorf Reported-by: Chris Wedgwood Cc: Jens Axboe Cc: Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Steven Rostedt --- drivers/block/brd.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/block/brd.c b/drivers/block/brd.c index 531ceb3..4e8213a 100644 --- a/drivers/block/brd.c +++ b/drivers/block/brd.c @@ -117,13 +117,13 @@ static struct page *brd_insert_page(struct brd_device *brd, sector_t sector) spin_lock(&brd->brd_lock); idx = sector >> PAGE_SECTORS_SHIFT; + page->index = idx; if (radix_tree_insert(&brd->brd_pages, idx, page)) { __free_page(page); page = radix_tree_lookup(&brd->brd_pages, idx); BUG_ON(!page); BUG_ON(page->index != idx); - } else - page->index = idx; + } spin_unlock(&brd->brd_lock); radix_tree_preload_end(); -- 1.7.10.4 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/