Comment 9 for bug 1383555

This was NOT happening in precise, and WAS happening with early versions of trusty. I had a test partition with trusty to check it, prior to fresh install of trusty. It was clear that this was happening with trusty from boot. I filed a bug report for trusty, along with upstream kernels that were checked. The newest upstream kernels did not show that errors from boot. When trusty was updated some time later, and this error did not present from boot, I took the opportunity to fresh install trusty, and use that full time. I reported that the error seemed to be fixed, and you closed the report. (Bug 1318837 )

(my comment from bug 1318837 follows) :-

have tried many kernels from mainline kernels
kernels from current, up to and including 3.14.0-rc2 exhibit error as described above.
kernels 3.14.0-rc3 and above DO NOT exhibit error as descibed above.
I have looked at changes log for for 3.14.0-rc3 for obvious changes that may be implicated, and found following candidate (search on "phy") (this may or may not be the solution)

Andrew Lunn (3):
      drivers: phy: Make NULL a valid phy reference
      drivers: phy: Add support for optional phys
      ata: sata_mv: Fix probe failures with optional phys