Commit-ID: b33e18f61bd18227a456016a77b1a968f5bc1d65 Gitweb: http://git.kernel.org/tip/b33e18f61bd18227a456016a77b1a968f5bc1d65 Author: Tejun Heo <[email protected]> AuthorDate: Tue, 27 Oct 2015 14:19:39 +0900 Committer: Ingo Molnar <[email protected]> CommitDate: Wed, 28 Oct 2015 13:17:30 +0100
fs/writeback, rcu: Don't use list_entry_rcu() for pointer offsetting in bdi_split_work_to_wbs() bdi_split_work_to_wbs() uses list_for_each_entry_rcu_continue() to walk @bdi->wb_list. To set up the initial iteration condition, it uses list_entry_rcu() to calculate the entry pointer corresponding to the list head; however, this isn't an actual RCU dereference and using list_entry_rcu() for it ended up breaking a proposed list_entry_rcu() change because it was feeding an non-lvalue pointer into the macro. Don't use the RCU variant for simple pointer offsetting. Use list_entry() instead. Reported-by: Ingo Molnar <[email protected]> Signed-off-by: Tejun Heo <[email protected]> Cc: Darren Hart <[email protected]> Cc: David Howells <[email protected]> Cc: Dipankar Sarma <[email protected]> Cc: Eric Dumazet <[email protected]> Cc: Frederic Weisbecker <[email protected]> Cc: Josh Triplett <[email protected]> Cc: Lai Jiangshan <[email protected]> Cc: Linus Torvalds <[email protected]> Cc: Mathieu Desnoyers <[email protected]> Cc: Oleg Nesterov <[email protected]> Cc: Patrick Marlier <[email protected]> Cc: Paul McKenney <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Steven Rostedt <[email protected]> Cc: Thomas Gleixner <[email protected]> Cc: pranith kumar <[email protected]> Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Ingo Molnar <[email protected]> --- fs/fs-writeback.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/fs/fs-writeback.c b/fs/fs-writeback.c index 29e4599..7378169 100644 --- a/fs/fs-writeback.c +++ b/fs/fs-writeback.c @@ -779,8 +779,8 @@ static void bdi_split_work_to_wbs(struct backing_dev_info *bdi, bool skip_if_busy) { struct bdi_writeback *last_wb = NULL; - struct bdi_writeback *wb = list_entry_rcu(&bdi->wb_list, - struct bdi_writeback, bdi_node); + struct bdi_writeback *wb = list_entry(&bdi->wb_list, + struct bdi_writeback, bdi_node); might_sleep(); restart: -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
