From: Yu Kuai <yukuai3@xxxxxxxxxx> The backgroud is that our customer is using brd for dm-thinpool, and they want brd to support discard. So today I'm reviewing the commit 9ead7efc6f3f ("brd: implement discard support") and try to backport it to downstream kernel. Those problems are found while backporting, they are not tested yet. Yu Kuai (5): brd: fix oops if write concurrent with discard brd: synchronize using page and free page with rcu brd: fix aligned_sector from brd_do_discard() brd: fix discard end sector brd: zero data for discard that is not aligned to page drivers/block/brd.c | 76 ++++++++++++++++++++++++++++++++------------- 1 file changed, 55 insertions(+), 21 deletions(-) -- 2.39.2