Kernel oops: fb: conflicting fb hw usage astdrmfb vs VESA VGA (unable to handle kernel NULL pointer dereference / con_set_unimap+0x32

Thank you for taking the time to report this bug and helping to make Ubuntu better. It seems that your bug report is not filed about a specific source package though, rather it is just filed against Ubuntu in general. It is important that bug reports be filed about source packages so that people interested in the package can find the bugs about it. You can find some hints about determining what package your bug might be about at https://wiki.ubuntu.com/Bugs/FindRightPackage. You might also ask for help in the #ubuntu-bugs irc channel on Freenode.

To change the source package that this bug is filed about visit https://bugs.launchpad.net/ubuntu/+bug/1296660/+editstatus and add the package name in the text box next to the word Package.

[This is an automated message. I apologize if it reached you inappropriately; please just reply to this message indicating so.]

I cannot enter the Package name. Apparently the problem is with the ast driver, i. e. /lib/modules/3.13.0-18-generic/kernel/drivers/gpu/drm/ast/ast.ko ; that belongs to the linux-image-extra-3.13.0-18-generic package.
Using the "Chose" option on the web page gives the same name. Nevertheless I get an error message ''There is no package named 'linux-image-extra-3.13.0-18-generic' published in Ubuntu.''

This bug is missing log files that will aid in diagnosing the problem. From a terminal window please run:

apport-collect 1296660

and then change the status of the bug to 'Confirmed'.

If, due to the nature of the issue you have encountered, you are unable to run this command, please add a comment stating that fact and change the bug status to 'Confirmed'.

This change has been made by an automated script, maintained by the Ubuntu Kernel Team.

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Obviously I can run the apport-collect command only in case of a successful boot, but not in the error case when the whole system hangs.

It renders the system temporarily or permanently unusable.

Never confirm your own bugs!

Dear Alberto,

In message <email address hidden> you wrote:
> Never confirm your own bugs!
>
> ** Changed in: linux (Ubuntu)
> Status: Confirmed => New

I agree that this seems strange, but that was what I have been asked
to do:

| >From a terminal window please run:
|
| apport-collect 1296660
|
| and then change the status of the bug to 'Confirmed'.
|
| If, due to the nature of the issue you have encountered, you are unable
| to run this command, please add a comment stating that fact and change
| the bug status to 'Confirmed'.

This explicitly says I should - in both cases - "change the status of
the bug to 'Confirmed'."

Best regards,

Wolfgang Denk

--
DENX Software Engineering GmbH, MD: Wolfgang Denk & Detlev Zundel
HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany
Phone: (+49)-8142-66989-10 Fax: (+49)-8142-66989-80 Email: <email address hidden>
A morsel of genuine history is a thing so rare as to be always
valuable. - Thomas Jefferson

This change was made by a bot.

El 25/03/14 17:58, Wolfgang Denk escribió:
> I agree that this seems strange, but that was what I have been asked
> to do:
It seems they decided to confirm by default, so everything is okay.

Would it be possible for you to test the latest upstream kernel? Refer to https://wiki.ubuntu.com/KernelMainlineBuilds . Please test the latest v3.14 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/v3.14-rc8-trusty/

kernel-fixed-upstream - v3.14-rc8 booted without problem in 6 successive tests

Thank you for taking the time to file a bug report on this issue.

However, given the number of bugs that the Kernel Team receives during any development cycle it is impossible for us to review them all. Therefore, we occasionally resort to using automated bots to request further testing. This is such a request.

  With the recent release of this Ubuntu release, would like to confirm if this bug is still present. Please test again with the newer kernel and indicate in the bug if this issue still exists or not.

You can update to the latest development kernel by simply running the following commands in a terminal window:

    sudo apt-get update
    sudo apt-get dist-upgrade

If the bug still exists, change the bug status from Incomplete to Confirmed. If the bug no longer exists, change the bug status from Incomplete to Fix Released.

If you want this bot to quit automatically requesting kernel tests, add a tag named: bot-stop-nagging.

 Thank you for your help, we really do appreciate it.

Joseph:
  I'm seeing an identical backtrace on one of my dads machines after upgrade to a recent kernel; it's intermittent perhaps 1/4 ish boots

3.13.0-32-generic, so I say not fixed:

Jul 22 17:58:13 thedr kernel: [ 16.146863] fb: conflicting fb hw usage inteldrmfb vs VESA VGA - removing generic driver
Jul 22 17:58:13 thedr kernel: [ 16.202062] Console: switching to colour dummy device 80x25
Jul 22 17:58:13 thedr kernel: [ 16.202085] BUG: unable to handle kernel NULL pointer dereference at 0000000000000138
Jul 22 17:58:13 thedr kernel: [ 16.202089] IP: [<ffffffff8145aad2>] con_set_unimap+0x32/0x290
Jul 22 17:58:13 thedr kernel: [ 16.202091] PGD c6dc1067 PUD c6d8d067 PMD 0
Jul 22 17:58:13 thedr kernel: [ 16.202092] Oops: 0000 [#1] SMP
Jul 22 17:58:13 thedr kernel: [ 16.202104] Modules linked in: intel_powerclamp snd_hda_codec coretemp i915(+) snd_hwdep lpc_ich snd_pcm snd_page_alloc kvm_intel kvm snd_seq_midi snd_seq_midi_event crct10dif_pclmul snd_rawmidi crc32_pclmul snd_seq drm_kms_helper drm i2c_algo_bit mei_me mei ghash_clmulni_intel cryptd snd_seq_device snd_timer wmi parport_pc snd video ppdev serio_raw soundcore mac_hid lp parport binfmt_misc hid_generic usbhid hid r8169 mii
Jul 22 17:58:13 thedr kernel: [ 16.202106] CPU: 1 PID: 593 Comm: setfont Not tainted 3.13.0-32-generic #57-Ubuntu
Jul 22 17:58:13 thedr kernel: [ 16.202106] Hardware name: System manufacturer System Product Name/P8H61-MX R2.0, BIOS 0504 06/29/2012
Jul 22 17:58:13 thedr kernel: [ 16.202107] task: ffff8802126cdfc0 ti: ffff8800c6c86000 task.ti: ffff8800c6c86000
Jul 22 17:58:13 thedr kernel: [ 16.202110] RIP: 0010:[<ffffffff8145aad2>] [<ffffffff8145aad2>] con_set_unimap+0x32/0x290
Jul 22 17:58:13 thedr kernel: [ 16.202110] RSP: 0018:ffff8800c6c87d48 EFLAGS: 00010246
Jul 22 17:58:13 thedr kernel: [ 16.202111] RAX: ffff88021740c308 RBX: 0000000000e58b10 RCX: 000000000000c710
Jul 22 17:58:13 thedr kernel: [ 16.202111] RDX: 0000000000001278 RSI: 0000000000000296 RDI: 0000000000000296
Jul 22 17:58:13 thedr kernel: [ 16.202112] RBP: ffff8800c6c87db0 R08: ffff8800c6c86000 R09: 0000000000000001
Jul 22 17:58:13 thedr kernel: [ 16.202113] R10: 0000000000000001 R11: ffffea0008424740 R12: 0000000000000000
Jul 22 17:58:13 thedr kernel: [ 16.202113] R13: 0000000000004b67 R14: ffff88021740c000 R15: ffff88021740c000
Jul 22 17:58:13 thedr kernel: [ 16.202114] FS: 00007fe0c4bf9740(0000) GS:ffff88021fb00000(0000) knlGS:0000000000000000
Jul 22 17:58:13 thedr kernel: [ 16.202115] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
Jul 22 17:58:13 thedr kernel: [ 16.202115] CR2: 0000000000000138 CR3: 00000000c6d92000 CR4: 00000000000407e0
Jul 22 17:58:13 thedr kernel: [ 16.202116] Stack:
Jul 22 17:58:13 thedr kernel: [ 16.202118] ffff8800c6c87d78 ffffffff813110ed ffff8802126cdfc0 0000000000000000
Jul 22 17:58:13 thedr kernel: [ 16.202119] 0000000000004b67 ffff88021740c000 000002e1c6c87d88 ffff88021740c000
Jul 22 17:58:13 thedr kernel: [ 16.202120] 0000000000000000 0000000000000000 0000000000004b67 ffff88021740c000
Jul 22 17:58:13 thedr kernel: [ 16.202120] Call Trace:
Jul 22 17:58:13 thedr kernel: [ 16.202125] [<ffffffff813110ed>] ?...

Hi, I am also getting similar traces on boot, not every time. The following is from a fresh net install on a ProLiant DL380 G7.

Oct 13 11:54:36 node21 kernel: [ 3.347415] [drm] radeon kernel modesetting enabled.
Oct 13 11:54:36 node21 kernel: [ 3.347490] checking generic (e8000000 130000) vs hw (e8000000 8000000)
Oct 13 11:54:36 node21 kernel: [ 3.347491] fb: conflicting fb hw usage radeondrmfb vs VESA VGA - removing generic driver
Oct 13 11:54:36 node21 kernel: [ 3.349507] Console: switching to colour dummy device 80x25
Oct 13 11:54:36 node21 kernel: [ 3.349524] BUG: unable to handle kernel NULL pointer dereference at 0000000000000138
Oct 13 11:54:36 node21 kernel: [ 3.349528] IP: [<ffffffff8145d382>] con_set_unimap+0x32/0x290
Oct 13 11:54:36 node21 kernel: [ 3.349531] PGD bdbef4067 PUD bdada8067 PMD 0
Oct 13 11:54:36 node21 kernel: [ 3.349532] Oops: 0000 [#1] SMP
Oct 13 11:54:36 node21 kernel: [ 3.349548] Modules linked in: intel_powerclamp radeon(+) coretemp kvm_intel kvm crct10dif_pclmul crc32_pclmul gpio_ich ghash_clmulni_intel ttm aesni_intel drm_kms_helper aes_x86_64 drm lrw gf128mul glue_helper ablk_helper i2c_algo_bit cryptd hpilo hpwdt i7core_edac joydev edac_core lpc_ich ipmi_si serio_raw mac_hid acpi_power_meter lp parport hid_generic usbhid hid psmouse bnx2 hpsa
Oct 13 11:54:36 node21 kernel: [ 3.349551] CPU: 22 PID: 700 Comm: setfont Tainted: G I 3.13.0-37-generic #64-Ubuntu
Oct 13 11:54:36 node21 kernel: [ 3.349552] Hardware name: HP ProLiant DL380 G7, BIOS P67 05/05/2011
Oct 13 11:54:36 node21 kernel: [ 3.349553] task: ffff8817da688000 ti: ffff880bd5d60000 task.ti: ffff880bd5d60000
Oct 13 11:54:36 node21 kernel: [ 3.349556] RIP: 0010:[<ffffffff8145d382>] [<ffffffff8145d382>] con_set_unimap+0x32/0x290
Oct 13 11:54:36 node21 kernel: [ 3.349557] RSP: 0018:ffff880bd5d61d48 EFLAGS: 00010246
Oct 13 11:54:36 node21 kernel: [ 3.349558] RAX: ffff880bdadd0b08 RBX: 0000000001c0bb10 RCX: 00000000c0000100
Oct 13 11:54:36 node21 kernel: [ 3.349558] RDX: 0000000000001530 RSI: 0000000000000296 RDI: 0000000000000296
Oct 13 11:54:36 node21 kernel: [ 3.349559] RBP: ffff880bd5d61db0 R08: ffff880bd5d60000 R09: 000000000000001c
Oct 13 11:54:36 node21 kernel: [ 3.349561] R10: 0000000000000054 R11: 000000000000004c R12: 0000000000000000
Oct 13 11:54:36 node21 kernel: [ 3.349562] R13: 0000000000004b67 R14: ffff880bdadd0800 R15: ffff880bdadd0800
Oct 13 11:54:36 node21 kernel: [ 3.349563] FS: 00007f81dbf6c740(0000) GS:ffff880befd60000(0000) knlGS:0000000000000000
Oct 13 11:54:36 node21 kernel: [ 3.349564] CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b
Oct 13 11:54:36 node21 kernel: [ 3.349565] CR2: 0000000000000138 CR3: 0000000bd5c8e000 CR4: 00000000000007e0
Oct 13 11:54:36 node21 kernel: [ 3.349566] Stack:
Oct 13 11:54:36 node21 kernel: [ 3.349571] ffff880bd5d61d78 ffffffff8131226d ffff8817da688000 0000000000000002
Oct 13 11:54:36 node21 kernel: [ 3.349575] 0000000000004b67 ffff880bdadd0800 000002e1d5d61d88 ffff880bdadd0800
Oct 13 11:54:36 node21 kernel: [ 3.349577] 0000000000000000 0000000000000002 0000000000004b67 ffff880bdadd0800
Oct 13 11:54:36 node...

Also seeing the issue here (on occasion) w/ 3.13.0-37-generic:

fb: conflicting fb hw usage nouveaufb vs VESA VGA - removing generic driver
Console: switching to colour dummy device 80x25
BUG: unable to handle kernel NULL pointer dereference at 0000000000000138
IP: [<ffffffff8145d382>] con_set_unimap+0x32/0x290
....
Call Trace:
[<ffffffff8131226d>] ? apparmor_capable+0x1d/0x130
[<ffffffff81457223>] vt_ioctl+0xe83/0x11c0
[<ffffffff8144ad3d>] tty_ioctl+0x26d/0xbb0
[<ffffffff811d03a0>] do_vfs_ioctl+0x2e0/0x4c0
[<ffffffff811d0601>] SyS_ioctl+0x81/0xa0
[<ffffffff8172f82d>] system_call_fastpath+0x1a/0x1f

I had the same problem with Ubuntu 12.04 and kernel 3.13.0-37-generic

This solution working:
http://askubuntu.com/questions/169912/fb-conflicting-fb-hw-usage-inteldrmfb-vs-efi-vga-removing-generic-driver

but is incomplette. That helped me to make permanent fix:

"
--- /etc/grub.d/10_linux 2014-10-22 15:22:09.749586332 +0200
+++ /etc/grub.d/10_linux 2014-10-22 15:08:09.908607933 +0200
@@ -95,9 +95,10 @@
   if ! ${recovery} ; then
       save_default_entry | sed -e "s/^/\t/"

- cat << EOF
- gfxmode \$linux_gfx_mode
-EOF
+# comment to fix "fb: conflicting fb hw usage inteldrmfb vs VESA VGA - removing generic driver"
+# cat << EOF
+# gfxmode \$linux_gfx_mode
+#EOF
   fi

   cat << EOF
"

ther run update-grub, reboot and the error message is gone. SInce the boot hang was occasional i cannot check it immediately, but if it happen with this fix ill report it back.

also hit this bug:
.......
Oct 29 09:04:14 spb-office kernel: [ 8.299240] [drm] Initialized drm 1.1.0 20060810
Oct 29 09:04:14 spb-office kernel: [ 8.337211] mei_me 0000:00:16.0: irq 45 for MSI/MSI-X
Oct 29 09:04:14 spb-office kernel: [ 8.537626] [drm] Memory usable by graphics device = 2048M
Oct 29 09:04:14 spb-office kernel: [ 8.537628] checking generic (e0000000 300000) vs hw (e0000000 10000000)
Oct 29 09:04:14 spb-office kernel: [ 8.537629] fb: conflicting fb hw usage inteldrmfb vs VESA VGA - removing generic driver
Oct 29 09:04:14 spb-office kernel: [ 8.561832] Console: switching to colour dummy device 80x25
Oct 29 09:04:14 spb-office kernel: [ 8.561844] BUG: unable to handle kernel NULL pointer dereference at 0000000000000138
Oct 29 09:04:14 spb-office kernel: [ 8.561848] IP: [<ffffffff8145ced2>] con_set_unimap+0x32/0x290
Oct 29 09:04:14 spb-office kernel: [ 8.561850] PGD c73dd067 PUD c73db067 PMD 0
Oct 29 09:04:14 spb-office kernel: [ 8.561851] Oops: 0000 [#1] SMP
Oct 29 09:04:14 spb-office kernel: [ 8.561862] Modules linked in: snd_hwdep kvm_intel i915(+) snd_pcm snd_page_alloc kvm crct10dif_pcl
mul mei_me crc32_pclmul drm_kms_helper snd_timer drm mei snd ghash_clmulni_intel soundcore cryptd i2c_algo_bit joydev lpc_ich wmi mac_hid
 video serio_raw lp parport hid_generic usbhid hid ahci psmouse libahci r8169 mii
Oct 29 09:04:14 spb-office kernel: [ 8.561864] CPU: 0 PID: 475 Comm: setfont Not tainted 3.13.0-36-generic #63-Ubuntu
Oct 29 09:04:14 spb-office kernel: [ 8.561864] Hardware name: System manufacturer System Product Name/P8H61-MX R2.0, BIOS 1102 06/04/2
013
Oct 29 09:04:14 spb-office kernel: [ 8.561865] task: ffff88003697e000 ti: ffff8800c600e000 task.ti: ffff8800c600e000
Oct 29 09:04:14 spb-office kernel: [ 8.561867] RIP: 0010:[<ffffffff8145ced2>] [<ffffffff8145ced2>] con_set_unimap+0x32/0x290
Oct 29 09:04:14 spb-office kernel: [ 8.561868] RSP: 0018:ffff8800c600fd48 EFLAGS: 00010246
Oct 29 09:04:14 spb-office kernel: [ 8.561869] RAX: ffff880035f46f08 RBX: 0000000000c88150 RCX: 0000000000000000
Oct 29 09:04:14 spb-office kernel: [ 8.561870] RDX: 0000000000001278 RSI: 0000000000000296 RDI: 0000000000000296
Oct 29 09:04:14 spb-office kernel: [ 8.561870] RBP: ffff8800c600fdb0 R08: ffff8800c600e000 R09: 0000000000000001
Oct 29 09:04:14 spb-office kernel: [ 8.561871] R10: 0000000000000001 R11: ffff880035b2d6be R12: 0000000000000000
Oct 29 09:04:14 spb-office kernel: [ 8.561871] R13: 0000000000004b67 R14: ffff880035f46c00 R15: ffff880035f46c00
Oct 29 09:04:14 spb-office kernel: [ 8.561872] FS: 00007f1770436740(0000) GS:ffff88011fa00000(0000) knlGS:0000000000000000
Oct 29 09:04:14 spb-office kernel: [ 8.561873] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
Oct 29 09:04:14 spb-office kernel: [ 8.561874] CR2: 0000000000000138 CR3: 00000000c71e1000 CR4: 00000000001407f0
Oct 29 09:04:14 spb-office kernel: [ 8.561874] Stack:
Oct 29 09:04:14 spb-office kernel: [ 8.561876] ffff8800c600fd78 ffffffff81311dfd ffff88003697e000 0000000000000005
Oct 29 09:04:14 spb-office kernel: [ 8.561878] 0000000000004b67 ffff880035f46c00 000001dac600fd88 ffff880035f46c00...

and here how it looks like on normal boot:
......
[drm] Initialized drm 1.1.0 20060810
Oct 29 09:09:30 spb-office kernel: [ 6.100409] mei_me 0000:00:16.0: irq 45 for MSI/MSI-X
Oct 29 09:09:30 spb-office kernel: [ 6.166581] [drm] Memory usable by graphics device = 2048M
Oct 29 09:09:30 spb-office kernel: [ 6.214256] i915 0000:00:02.0: irq 46 for MSI/MSI-X
Oct 29 09:09:30 spb-office kernel: [ 6.214272] [drm] Supports vblank timestamp caching Rev 2 (21.10.2013).
Oct 29 09:09:30 spb-office kernel: [ 6.214274] [drm] Driver supports precise vblank timestamp query.
Oct 29 09:09:30 spb-office kernel: [ 6.214374] vgaarb: device changed decodes: PCI:0000:00:02.0,olddecodes=io+mem,decodes=io+mem:owns=
io+mem
Oct 29 09:09:30 spb-office kernel: [ 6.299190] fbcon: inteldrmfb (fb0) is primary device
Oct 29 09:09:30 spb-office kernel: [ 6.492114] Console: switching to colour frame buffer device 180x56
Oct 29 09:09:30 spb-office kernel: [ 6.494227] i915 0000:00:02.0: fb0: inteldrmfb frame buffer device
Oct 29 09:09:30 spb-office kernel: [ 6.494228] i915 0000:00:02.0: registered panic notifier
Oct 29 09:09:30 spb-office kernel: [ 6.510108] ACPI: Video Device [GFX0] (multi-head: yes rom: no post: no)
Oct 29 09:09:30 spb-office kernel: [ 6.510269] acpi device:36: registered as cooling_device9
Oct 29 09:09:30 spb-office kernel: [ 6.510321] input: Video Bus as /devices/LNXSYSTM:00/device:00/PNP0A08:00/LNXVIDEO:00/input/input7
Oct 29 09:09:30 spb-office kernel: [ 6.510386] [drm] Initialized i915 1.6.0 20080730 for 0000:00:02.0 on minor 0
Oct 29 09:09:30 spb-office kernel: [ 6.510677] snd_hda_intel 0000:00:1b.0: irq 47 for MSI/MSI-X
.....

reproducible with 3.13.0-40-generic
Ubuntu 3.13.0-40.69~precise1-generic 3.13.11.10

Dec 5 16:49:56 ubuntu kernel: [ 21.340139] [drm] AST 2300 detected
Dec 5 16:49:56 ubuntu kernel: [ 21.340183] [drm] dram 1632000000 1 16 00800000
Dec 5 16:49:56 ubuntu kernel: [ 21.340211] [TTM] Zone kernel: Available graphics memory: 65964816 kiB
Dec 5 16:49:56 ubuntu kernel: [ 21.340211] [TTM] Zone dma32: Available graphics memory: 2097152 kiB
Dec 5 16:49:56 ubuntu kernel: [ 21.340212] [TTM] Initializing pool allocator
Dec 5 16:49:56 ubuntu kernel: [ 21.340214] [TTM] Initializing DMA pool allocator
Dec 5 16:49:56 ubuntu kernel: [ 21.354338] checking generic (c7000000 130000) vs hw (c7000000 800000)
Dec 5 16:49:56 ubuntu kernel: [ 21.354339] fb: conflicting fb hw usage astdrmfb vs VESA VGA - removing generic driver
Dec 5 16:49:56 ubuntu kernel: [ 21.394467] Console: switching to colour dummy device 80x25
Dec 5 16:49:56 ubuntu kernel: [ 21.394513] BUG: unable to handle kernel NULL pointer dereference at 0000000000000138
Dec 5 16:49:56 ubuntu kernel: [ 21.394517] IP: [<ffffffff8147abd4>] con_set_unimap+0x34/0x2a0
Dec 5 16:49:56 ubuntu kernel: [ 21.394518] PGD 10267e2067 PUD 1025232067 PMD 0
Dec 5 16:49:56 ubuntu kernel: [ 21.394519] Oops: 0000 [#1] SMP
Dec 5 16:49:56 ubuntu kernel: [ 21.394527] Modules linked in: ast(+) ttm drm_kms_helper drm gpio_ich sysimgblt sysfillrect syscopyarea shpchp lpc_ich wmi joydev ipmi_si parport_pc ppdev mac_hid acpi_pad lp parport hid_generic usbhid hid mpt2sas igb dca ahci scsi_transport_sas i2c_algo_bit raid_class ptp libahci pps_core
Dec 5 16:49:56 ubuntu kernel: [ 21.394528] CPU: 4 PID: 1649 Comm: setfont Not tainted 3.13.0-40-generic #69~precise1-Ubuntu
Dec 5 16:49:56 ubuntu kernel: [ 21.394529] Hardware name: Quanta Computer Inc T41S-2U/S2S, BIOS S2S_3A14 09/19/2014
Dec 5 16:49:56 ubuntu kernel: [ 21.394529] task: ffff88202467c800 ti: ffff8820270da000 task.ti: ffff8820270da000
Dec 5 16:49:56 ubuntu kernel: [ 21.394531] RIP: 0010:[<ffffffff8147abd4>] [<ffffffff8147abd4>] con_set_unimap+0x34/0x2a0
Dec 5 16:49:56 ubuntu kernel: [ 21.394531] RSP: 0018:ffff8820270dbd18 EFLAGS: 00010246
Dec 5 16:49:56 ubuntu kernel: [ 21.394532] RAX: ffff8820262a8308 RBX: 0000000000004b67 RCX: 0000000000000000
Dec 5 16:49:56 ubuntu kernel: [ 21.394532] RDX: ffff8820262a8000 RSI: 0000000000000296 RDI: 0000000000000000
Dec 5 16:49:56 ubuntu kernel: [ 21.394533] RBP: ffff8820270dbd98 R08: ffff8820270da000 R09: 0000000000000001
Dec 5 16:49:56 ubuntu kernel: [ 21.394533] R10: 0000000000000020 R11: 0000000000000000 R12: 00000000ffffffff
Dec 5 16:49:56 ubuntu kernel: [ 21.394533] R13: 00000000021f9b10 R14: 0000000000000001 R15: 0000000000000000
Dec 5 16:49:56 ubuntu kernel: [ 21.394534] FS: 00007f9209142700(0000) GS:ffff88103fc80000(0000) knlGS:0000000000000000
Dec 5 16:49:56 ubuntu kernel: [ 21.394534] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
Dec 5 16:49:56 ubuntu kernel: [ 21.394535] CR2: 0000000000000138 CR3: 000000101f230000 CR4: 00000000001407e0
Dec 5 16:49:56 ubuntu kernel: [ 21.394535] Stack:
Dec 5 16:49:56 ubuntu kernel: [ 21.394537]...

Still in 3.13.0-43-generic.

Furthermore, I have a strong suspicion this was fixed upstream in v3.18, even though Wolfgang reported v3.14 worked fine for him.

https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=9e326f78713a4421fe11afc2ddeac07698fac131

Can anyone test and confirm this solves the issue? I'm affected, though testing is tricky without console access.

Actually, the patch posted above appears to be included in 3.13.0-44.73, which is currently in proposed (also see: #1402853).

I suppose that warrants a 'Fix Released' status, though I'll leave that to the Ubuntu kernel team.

Have rebooted 40 times without this issue with 3.13.0-44 (linux-headers-3.13.0-44-generic, linux-image-3.13.0-44-generic and linux-image-extra-3.13.0-44-generic).