The S&P 500 rose 0.6% and was on track to top its all-time high set two weeks ago. The Dow Jones Industrial Average was up 251 points, or 0.6%, as of 9:35 a.m. Eastern time, while the Nasdaq composite was 0.7% higher and also heading toward a record.

Wall Street’s record-setting rally is due for a reality check, according to the latest report from Stifel’s Barry Bannister and Thomas Carroll.

Warren Buffett is telling investors something -- not through what he has said, but through his actions with the balance sheet of his investment conglomerate Berkshire Hathaway ( BRK.A -0.40%) ( BRK.B 0.83%). These actions should be taken as a warning sign with the stock market reaching elevated valuation levels in recent months.