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[ Upstream commit a91b750fd6629354460282bbf5146c01b05c4859 ] syzbot is reporting lockdep warning at rds_tcp_reset_callbacks() [1], for commit ac3615e7f3cffe2a ("RDS: TCP: Reduce code duplication in rds_tcp_reset_callbacks()") added cancel_delayed_work_sync() into a section protected by lock_sock() without realizing that rds_send_xmit() might call lock_sock(). We don't need to protect cancel_delayed_work_sync() using lock_sock(), for even if rds_{send,recv}_worker() re-queued this work while __flush_work() from cancel_delayed_work_sync() was waiting for this work to complete, retried rds_{send,recv}_worker() is no-op due to the absence of RDS_CONN_UP bit. Link: https://syzkaller.appspot.com/bug?extid=78c55c7bc6f66e53dce2 [1] Reported-by: syzbot <syzbot+78c55c7bc6f66e53dce2@syzkaller.appspotmail.com> Co-developed-by: Hillf Danton <hdanton@sina.com> Signed-off-by: Hillf Danton <hdanton@sina.com> Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Tested-by: syzbot <syzbot+78c55c7bc6f66e53dce2@syzkaller.appspotmail.com> Fixes: ac3615e7f3cffe2a ("RDS: TCP: Reduce code duplication in rds_tcp_reset_callbacks()") Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Sasha Levin <sashal@kernel.org>