Commit-ID: b33e18f61bd18227a456016a77b1a968f5bc1d65 Gitweb: http://git.kernel.org/tip/b33e18f61bd18227a456016a77b1a968f5bc1d65 Author: Tejun Heo <t...@kernel.org> AuthorDate: Tue, 27 Oct 2015 14:19:39 +0900 Committer: Ingo Molnar <mi...@kernel.org> 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 <mi...@kernel.org> Signed-off-by: Tejun Heo <t...@kernel.org> Cc: Darren Hart <dvh...@linux.intel.com> Cc: David Howells <dhowe...@redhat.com> Cc: Dipankar Sarma <dipan...@in.ibm.com> Cc: Eric Dumazet <eduma...@google.com> Cc: Frederic Weisbecker <fweis...@gmail.com> Cc: Josh Triplett <j...@joshtriplett.org> Cc: Lai Jiangshan <jiangshan...@gmail.com> Cc: Linus Torvalds <torva...@linux-foundation.org> Cc: Mathieu Desnoyers <mathieu.desnoy...@efficios.com> Cc: Oleg Nesterov <o...@redhat.com> Cc: Patrick Marlier <patrick.marl...@gmail.com> Cc: Paul McKenney <paul...@linux.vnet.ibm.com> Cc: Peter Zijlstra <pet...@infradead.org> Cc: Steven Rostedt <rost...@goodmis.org> Cc: Thomas Gleixner <t...@linutronix.de> Cc: pranith kumar <bobby.pr...@gmail.com> Link: http://lkml.kernel.org/r/20151027051939.ga19...@mtj.duckdns.org Signed-off-by: Ingo Molnar <mi...@kernel.org> --- 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 majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
