Following call trace is seen in the dmesg. Looks like it is related to the GPU driver.
[ 9.107564] ------------[ cut here ]------------
[ 9.107589] WARNING: CPU: 2 PID: 390 at /build/buildd/linux-3.18.0/drivers/gpu/drm/i915/i915_drv.c:451 intel_detect_pch+0x366/0x3d0 [i915]()
[ 9.107607] Modules linked in: i915(+) x86_pkg_temp_thermal coretemp kvm_intel kvm crct10dif_pclmul crc32_pclmul ghash_clmulni_intel aesni_intel drm_kms_helper aes_x86_64 lrw gf128mul glue_helper ablk_helper cryptd drm i2c_algo_bit ipmi_si(+) lpc_ich ipmi_msghandler shpchp video mac_hid mlx4_en vxlan ip6_udp_tunnel udp_tunnel ptp pps_core mlx4_core ahci libahci
[ 9.107610] CPU: 2 PID: 390 Comm: systemd-udevd Not tainted 3.18.0-11-generic #12-Ubuntu
[ 9.107611] Hardware name: HP ProLiant m710 Server Cartridge/, BIOS H06 01/21/2015
[ 9.107614] 0000000000000009 ffff880810d93878 ffffffff817ad3ac 000000000d900d90
[ 9.107616] 0000000000000000 ffff880810d938b8 ffffffff81074c21 0000000000000000
[ 9.107618] ffff880812945000 ffff880810c00000 ffff88081011e800 ffff880810c00000
[ 9.107618] Call Trace:
[ 9.107624] [<ffffffff817ad3ac>] dump_stack+0x46/0x58
[ 9.107627] [<ffffffff81074c21>] warn_slowpath_common+0x81/0xa0
[ 9.107630] [<ffffffff81074cfa>] warn_slowpath_null+0x1a/0x20
[ 9.107648] [<ffffffffc05db756>] intel_detect_pch+0x366/0x3d0 [i915]
[ 9.107687] [<ffffffffc06751d8>] i915_driver_load+0x1b8/0x1030 [i915]
[ 9.107690] [<ffffffff813b6c18>] ? kobject_uevent_env+0x178/0x690
[ 9.107693] [<ffffffff814e7707>] ? get_device+0x17/0x30
[ 9.107695] [<ffffffff814ed385>] ? klist_class_dev_get+0x15/0x20
[ 9.107697] [<ffffffff8179f858>] ? klist_node_init+0x38/0x60
[ 9.107700] [<ffffffff8179f916>] ? klist_add_tail+0x46/0x50
[ 9.107702] [<ffffffff814e902b>] ? device_add+0x1db/0x6d0
[ 9.107715] [<ffffffffc037f6c5>] drm_dev_register+0xb5/0x110 [drm]
[ 9.107726] [<ffffffffc038273d>] drm_get_pci_dev+0x8d/0x200 [drm]
[ 9.107744] [<ffffffffc05db23b>] i915_pci_probe+0x3b/0x60 [i915]
[ 9.107748] [<ffffffff813fc0d5>] local_pci_probe+0x45/0xa0
[ 9.107750] [<ffffffff813fd475>] ? pci_match_device+0xe5/0x110
[ 9.107752] [<ffffffff813fd5b9>] pci_device_probe+0xd9/0x130
[ 9.107756] [<ffffffff814ec413>] driver_probe_device+0xa3/0x410
[ 9.107758] [<ffffffff814ec85b>] __driver_attach+0x9b/0xa0
[ 9.107761] [<ffffffff814ec7c0>] ? __device_attach+0x40/0x40
[ 9.107763] [<ffffffff814ea1eb>] bus_for_each_dev+0x6b/0xb0
[ 9.107766] [<ffffffff814ebe7e>] driver_attach+0x1e/0x20
[ 9.107768] [<ffffffff814eba60>] bus_add_driver+0x180/0x250
[ 9.107770] [<ffffffff814ed054>] driver_register+0x64/0xf0
[ 9.107773] [<ffffffff813fb90c>] __pci_register_driver+0x4c/0x50
[ 9.107783] [<ffffffffc03829aa>] drm_pci_init+0xfa/0x130 [drm]
[ 9.107785] [<ffffffffc051e000>] ? 0xffffffffc051e000
[ 9.107802] [<ffffffffc051e08a>] i915_init+0x8a/0x92 [i915]
[ 9.107806] [<ffffffff81002148>] do_one_initcall+0xd8/0x210
[ 9.107810] [<ffffffff811b8cf2>] ? __vunmap+0xa2/0x100
[ 9.107814] [<ffffffff810fb32b>] load_module+0x151b/0x1c10
[ 9.107816] [<ffffffff810f6a40>] ? store_uevent+0x40/0x40
[ 9.107819] [<ffffffff810fbb96>] SyS_finit_module+0x86/0xb0
[ 9.107822] [<ffffffff817b506d>] system_call_fastpath+0x16/0x1b
[ 9.107824] ---[ end trace 58c91eee44705aff ]---
This bug is awaiting verification that the kernel in -proposed solves the problem. Please test the kernel and update this bug with the results. If the problem is solved, change the tag 'verification-
If verification is not done by 5 working days from today, this fix will be dropped from the source code, and this bug will be closed.
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