Hi,
I have found a workaround for this bug: 
Start the machine from scratch with all the USB devices plugged in.
Wait for the Grub menu to show on the screen.
Using the keyboard select Ubuntu as the operating system to load.
Immediately after selecting the Ubuntu OS, disconnect the USB mouse (be
it direct USB plug-in or remote).
When the Ubuntu login screen comes up it will be possible to use the
keyboard to enter the user-name and the password.
Once the Ubuntu environment is established, reconnect the USB mouse.,
and use it 
normally.
Problem solved, although a bit annoying.
Hope this helps.

-- 
  Dr Joseph D. Wallach
  <email address hidden>

On Fri, May 29, 2015, at 12:44 PM, Steve Cohen wrote:
> What, please, is the status of this bug?  Is there a fix or candidate
> fix in any newer version of the kernel?
> 
> Since I signed on to this bug in early April, I have been looking for
> some resolution to it.  For awhile I was checking each new kernel
> release to see if the bug was fixed.   I have downgraded to 3.13.0-46,
> the last version that works with my computer.  The later releases can
> not even be installed by the auto-installer.
> 
> -- 
> You received this bug notification because you are subscribed to the bug
> report.
> https://bugs.launchpad.net/bugs/1440174
> 
> Title:
>   Keyboard and Mouse don't work with latest Kernel
> 
> Status in linux package in Ubuntu:
>   Incomplete
> 
> Bug description:
>   1)
>   Description:    Ubuntu 14.04.2 LTS
>   Release:        14.04
> 
>   2) Linux / The kernel
> 
>   3) I expected my usb devices to work on the login page
> 
>   4) They don't work :)
> 
>   ...
> 
>   Upon the upgrade to kernel 3.13.0-48-generic my USB devices don't
>   work, so when I did a normal launch of my computer, I could not sign
>   into it since my usb devices were not working.
> 
>   I was able to sign and and use my computer as normal when I revert to
>   kernel 3.13.0-46-generic.
> 
>   ProblemType: Bug
>   DistroRelease: Ubuntu 14.04
>   Package: linux-image-3.13.0-46-generic 3.13.0-46.79
>   ProcVersionSignature: Ubuntu 3.13.0-46.79-generic 3.13.11-ckt15
>   Uname: Linux 3.13.0-46-generic x86_64
>   ApportVersion: 2.14.1-0ubuntu3.8
>   Architecture: amd64
>   CurrentDesktop: Unity
>   Date: Fri Apr  3 13:06:36 2015
>   HibernationDevice: RESUME=UUID=ae54d2d5-4931-4fcc-8996-aa3adf03cbb6
>   InstallationDate: Installed on 2015-01-01 (92 days ago)
>   InstallationMedia: Ubuntu 14.04.1 LTS "Trusty Tahr" - Release amd64
>   (20140722.2)
>   MachineType: Dell Inc. Inspiron 3847
>   ProcFB: 0 inteldrmfb
>   ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-3.13.0-46-generic
>   root=UUID=32967a77-1e86-4f47-abfd-a3b98a6e9af6 ro quiet splash
>   vt.handoff=7
>   RelatedPackageVersions:
>    linux-restricted-modules-3.13.0-46-generic N/A
>    linux-backports-modules-3.13.0-46-generic  N/A
>    linux-firmware                             1.127.11
>   RfKill:
>    0: phy0: Wireless LAN
>    	Soft blocked: no
>    	Hard blocked: no
>   SourcePackage: linux
>   UpgradeStatus: No upgrade log present (probably fresh install)
>   dmi.bios.date: 04/03/2014
>   dmi.bios.vendor: Dell Inc.
>   dmi.bios.version: A04
>   dmi.board.name: 088DT1
>   dmi.board.vendor: Dell Inc.
>   dmi.board.version: A01
>   dmi.chassis.type: 3
>   dmi.chassis.vendor: Dell Inc.
>   dmi.modalias:
>   dmi:bvnDellInc.:bvrA04:bd04/03/2014:svnDellInc.:pnInspiron3847:pvr:rvnDellInc.:rn088DT1:rvrA01:cvnDellInc.:ct3:cvr:
>   dmi.product.name: Inspiron 3847
>   dmi.sys.vendor: Dell Inc.
> 
> To manage notifications about this bug go to:
> https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1440174/+subscriptions

-- 
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