------------[ cut here ]------------ MMIO read or write has been dropped ffffffff

[Hatem MASMOUDI]

MMIO read or write has been dropped ffffffff

ProblemType: Bug
DistroRelease: Ubuntu 14.04
Package: linux-image-3.13.0-24-generic 3.13.0-24.46 [modified: boot/vmlinuz-3.13.0-24-generic]
ProcVersionSignature: Ubuntu 3.13.0-24.46-generic 3.13.9
Uname: Linux 3.13.0-24-generic x86_64
ApportVersion: 2.14.1-0ubuntu3
Architecture: amd64
AudioDevicesInUse:
 USER PID ACCESS COMMAND
 /dev/snd/controlC0: hmasmoudi 1688 F.... pulseaudio
CurrentDesktop: Unity
Date: Thu Apr 24 21:33:20 2014
HibernationDevice: RESUME=UUID=b3555db0-0ee7-4665-95aa-f867824e8841
InstallationDate: Installed on 2014-04-13 (11 days ago)
InstallationMedia: Ubuntu 14.04 LTS "Trusty Tahr" - Daily amd64 (20140412)
MachineType: Dell Inc. Inspiron 3521
ProcFB: 0 inteldrmfb
ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-3.13.0-24-generic root=UUID=34164dad-c85e-499f-9c70-7cfa407e8712 ro quiet splash acpi_backlight=vendor
RelatedPackageVersions:
 linux-restricted-modules-3.13.0-24-generic N/A
 linux-backports-modules-3.13.0-24-generic N/A
 linux-firmware 1.127
SourcePackage: linux
StagingDrivers: rts5139
UpgradeStatus: No upgrade log present (probably fresh install)
dmi.bios.date: 10/25/2013
dmi.bios.vendor: Dell Inc.
dmi.bios.version: A12
dmi.board.name: 0FXP6Y
dmi.board.vendor: Dell Inc.
dmi.board.version: A00
dmi.chassis.type: 8
dmi.chassis.vendor: Dell Inc.
dmi.chassis.version: A12
dmi.modalias: dmi:bvnDellInc.:bvrA12:bd10/25/2013:svnDellInc.:pnInspiron3521:pvrA12:rvnDellInc.:rn0FXP6Y:rvrA00:cvnDellInc.:ct8:cvrA12:
dmi.product.name: Inspiron 3521
dmi.product.version: A12
dmi.sys.vendor: Dell Inc.

[Brad Figg (brad-figg)]

This change was made by a bot.

[Joseph Salisbury (jsalisbury)]

Did this issue start happening after an update/upgrade? Was there a kernel version where you were not having this particular problem? This will help determine if the problem you are seeing is the result of the introduction of a regression, and when this regression was introduced. If this is a regression, we can perform a kernel bisect to identify the commit that introduced the problem.

[Joseph Salisbury (jsalisbury)]

Would it be possible for you to test the latest upstream kernel? Refer to https://wiki.ubuntu.com/KernelMainlineBuilds . Please test the latest v3.15 kernel[0].

If this bug is fixed in the mainline kernel, please add the following tag 'kernel-fixed-upstream'.

If the mainline kernel does not fix this bug, please add the tag: 'kernel-bug-exists-upstream'.

If you are unable to test the mainline kernel, for example it will not boot, please add the tag: 'kernel-unable-to-test-upstream'.
Once testing of the upstream kernel is complete, please mark this bug as "Confirmed".

Thanks in advance.

[0] http://kernel.ubuntu.com/~kernel-ppa/mainline/v3.15-rc2-trusty/

[Chris J Arges (arges)]

Hit this same bug on my X220. Will try mainline and see if it happens again.
Similar reports:
https://bugs.launchpad.net/ubuntu/+source/xorg/+bug/1312996
https://bugzilla.redhat.com/show_bug.cgi?id=1060387

[Brad Figg (brad-figg)]

This change was made by a bot.

[Hatem MASMOUDI (hatem-masmoudi)]

Hi,

Using the last version Linux 3.15 Rc2 from mainline, no more issue.

[penalvch (penalvch)]

Hatem MASMOUDI, the next step is to fully reverse commit bisect in order to identify the fix commit. Could you please do this following https://wiki.ubuntu.com/Kernel/KernelBisection#How_do_I_reverse_bisect_the_upstream_kernel.3F ?