lspci -> 03:00.0 Ethernet controller: Intel Corporation 82599EB 10-Gigabit SFI/SFP+ Netwo rk Connection (rev 01) 03:00.1 Ethernet controller: Intel Corporation 82599EB 10-Gigabit SFI/SFP+ Netwo rk Connection (rev 01) With the fibre 10Gbs SFP occasionally on reboot we get [ 15.104726] ixgbe 0000:03:00.0 eth0: detected SFP+: 5 [ 19.735155] ixgbe 0000:03:00.0 eth0: setup link failed with code -14 Probably about 1 in 10 boots. With the 1Gbs Copper SFP it works fine. kernel 3.14.8 worked fine, but on upgrading to 3.16.1 it fails in this way. I have narrowed it down to the commit https://git.kernel.org/cgit/linux/kernel/git/stable/linux-stable.git/commit/?id=ee98b577e7711d5890ded2c7b05578a29512bd39 I don't know enough about the hardware to understand why the change sometimes causes the failure, and was hoping someone else would. Reverting this commit on 3.16.1 fixes the issue. If you need any more information please ask.
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