I am hitting a similar problem: oblong@displaywall-left:~$ more /etc/issue Ubuntu 12.04.3 LTS \n \l oblong@displaywall-left:~$ uname -a Linux displaywall-left 3.8.0-29-generic #42~precise1-Ubuntu SMP Wed Aug 14 16:19:23 UTC 2013 x86_64 x86_64 x86_64 GNU/Linux oblong@displaywall-left:~$ grep Driver /var/log/Xorg.0.log [ 14.980] (II) NVIDIA dlloader X Driver 331.38 Wed Jan 8 18:51:00 PST 2014 The machine has three nVidia K5000 cards When I exit my application, X freezes and the following messages are dumped into /var/log/syslog: Mar 11 18:51:46 displaywall-left kernel: [ 9283.034123] NVRM: os_pci_init_handle: invalid context! Mar 11 18:51:46 displaywall-left kernel: [ 9283.034132] NVRM: os_pci_init_handle: invalid context! Mar 11 18:51:46 displaywall-left kernel: [ 9283.034135] NVRM: os_pci_init_handle: invalid context! Mar 11 18:51:46 displaywall-left kernel: [ 9283.034138] NVRM: os_pci_init_handle: invalid context! Mar 11 18:51:46 displaywall-left kernel: [ 9283.034141] NVRM: os_pci_init_handle: invalid context! Mar 11 18:51:46 displaywall-left kernel: [ 9283.034144] NVRM: os_pci_init_handle: invalid context! Mar 11 18:51:46 displaywall-left kernel: [ 9283.034147] NVRM: os_pci_init_handle: invalid context! Mar 11 18:51:46 displaywall-left kernel: [ 9283.034150] NVRM: os_pci_init_handle: invalid context! Mar 11 18:51:46 displaywall-left kernel: [ 9283.034153] NVRM: os_pci_init_handle: invalid context! Mar 11 18:51:46 displaywall-left kernel: [ 9283.034155] NVRM: os_pci_init_handle: invalid context! Mar 11 18:51:46 displaywall-left kernel: [ 9283.034158] NVRM: os_pci_init_handle: invalid context! Mar 11 18:51:46 displaywall-left kernel: [ 9283.034161] NVRM: os_pci_init_handle: invalid context! Mar 11 18:51:46 displaywall-left kernel: [ 9283.034182] NVRM: os_pci_init_handle: invalid context! Mar 11 18:51:46 displaywall-left kernel: [ 9283.034190] NVRM: GPU at 0000:02:00: GPU-d94bdba3-b53b-db31-e87c-b284bea2b29c Mar 11 18:51:46 displaywall-left kernel: [ 9283.034196] NVRM: Xid (0000:02:00): 31, Ch 00000003, engmask 00000111, intr 10000000 Mar 11 18:51:46 displaywall-left kernel: [ 9283.035525] NVRM: os_pci_init_handle: invalid context! Mar 11 18:51:46 displaywall-left kernel: [ 9283.035530] NVRM: os_pci_init_handle: invalid context! Mar 11 18:51:46 displaywall-left kernel: [ 9283.035533] NVRM: os_pci_init_handle: invalid context! Mar 11 18:51:46 displaywall-left kernel: [ 9283.035536] NVRM: os_pci_init_handle: invalid context! Mar 11 18:51:46 displaywall-left kernel: [ 9283.035539] NVRM: os_pci_init_handle: invalid context! Mar 11 18:51:46 displaywall-left kernel: [ 9283.035542] NVRM: os_pci_init_handle: invalid context! Mar 11 18:51:46 displaywall-left kernel: [ 9283.035544] NVRM: os_pci_init_handle: invalid context! Mar 11 18:51:46 displaywall-left kernel: [ 9283.035547] NVRM: os_pci_init_handle: invalid context! Mar 11 18:51:46 displaywall-left kernel: [ 9283.035550] NVRM: os_pci_init_handle: invalid context! Mar 11 18:51:46 displaywall-left kernel: [ 9283.035553] NVRM: os_pci_init_handle: invalid context! Mar 11 18:51:46 displaywall-left kernel: [ 9283.035556] NVRM: os_pci_init_handle: invalid context! Mar 11 18:51:46 displaywall-left kernel: [ 9283.035559] NVRM: os_pci_init_handle: invalid context! Mar 11 18:51:46 displaywall-left kernel: [ 9283.035562] NVRM: os_pci_init_handle: invalid context! Mar 11 18:51:46 displaywall-left kernel: [ 9283.035568] NVRM: Xid (0000:02:00): 13, 0003 00000000 0000902d 000002e0 00000000 00000000 Mar 11 18:51:46 displaywall-left kernel: [ 9283.036578] NVRM: os_pci_init_handle: invalid context! Mar 11 18:51:46 displaywall-left kernel: [ 9283.036583] NVRM: os_pci_init_handle: invalid context! Mar 11 18:51:46 displaywall-left kernel: [ 9283.036586] NVRM: os_pci_init_handle: invalid context! Mar 11 18:51:46 displaywall-left kernel: [ 9283.036589] NVRM: os_pci_init_handle: invalid context! Mar 11 18:51:46 displaywall-left kernel: [ 9283.036592] NVRM: os_pci_init_handle: invalid context! Mar 11 18:51:46 displaywall-left kernel: [ 9283.036595] NVRM: os_pci_init_handle: invalid context! Mar 11 18:51:46 displaywall-left kernel: [ 9283.036598] NVRM: os_pci_init_handle: invalid context! Mar 11 18:51:46 displaywall-left kernel: [ 9283.036601] NVRM: os_pci_init_handle: invalid context! Mar 11 18:51:46 displaywall-left kernel: [ 9283.036604] NVRM: os_pci_init_handle: invalid context! Mar 11 18:51:46 displaywall-left kernel: [ 9283.036607] NVRM: os_pci_init_handle: invalid context! Mar 11 18:51:46 displaywall-left kernel: [ 9283.036610] NVRM: os_pci_init_handle: invalid context! Mar 11 18:51:46 displaywall-left kernel: [ 9283.036613] NVRM: os_pci_init_handle: invalid context! Mar 11 18:51:46 displaywall-left kernel: [ 9283.036616] NVRM: os_pci_init_handle: invalid context! Mar 11 18:51:46 displaywall-left kernel: [ 9283.036622] NVRM: GPU at 0000:03:00: GPU-6cec9aba-d7ca-7aee-b33b-265c9933d2f3 Mar 11 18:51:46 displaywall-left kernel: [ 9283.036626] NVRM: Xid (0000:03:00): 31, Ch 00000003, engmask 00000111, intr 10000000 Mar 11 18:51:46 displaywall-left kernel: [ 9283.037852] NVRM: os_pci_init_handle: invalid context! Mar 11 18:51:46 displaywall-left kernel: [ 9283.037857] NVRM: os_pci_init_handle: invalid context! Mar 11 18:51:46 displaywall-left kernel: [ 9283.037860] NVRM: os_pci_init_handle: invalid context! Mar 11 18:51:46 displaywall-left kernel: [ 9283.037863] NVRM: os_pci_init_handle: invalid context! Mar 11 18:51:46 displaywall-left kernel: [ 9283.037866] NVRM: os_pci_init_handle: invalid context! Mar 11 18:51:46 displaywall-left kernel: [ 9283.037868] NVRM: os_pci_init_handle: invalid context! Mar 11 18:51:46 displaywall-left kernel: [ 9283.037872] NVRM: os_pci_init_handle: invalid context! Mar 11 18:51:46 displaywall-left kernel: [ 9283.037874] NVRM: os_pci_init_handle: invalid context! Mar 11 18:51:46 displaywall-left kernel: [ 9283.037877] NVRM: os_pci_init_handle: invalid context! Mar 11 18:51:46 displaywall-left kernel: [ 9283.037880] NVRM: os_pci_init_handle: invalid context! Mar 11 18:51:46 displaywall-left kernel: [ 9283.037883] NVRM: os_pci_init_handle: invalid context! Mar 11 18:51:46 displaywall-left kernel: [ 9283.037886] NVRM: os_pci_init_handle: invalid context! Mar 11 18:51:46 displaywall-left kernel: [ 9283.037889] NVRM: os_pci_init_handle: invalid context! Mar 11 18:51:46 displaywall-left kernel: [ 9283.037895] NVRM: Xid (0000:03:00): 13, 0003 00000000 0000902d 000002e0 00000000 00000000 Mar 11 18:51:46 displaywall-left kernel: [ 9283.039029] NVRM: os_pci_init_handle: invalid context! Mar 11 18:51:46 displaywall-left kernel: [ 9283.039035] NVRM: os_pci_init_handle: invalid context! Mar 11 18:51:46 displaywall-left kernel: [ 9283.039038] NVRM: os_pci_init_handle: invalid context! Mar 11 18:51:46 displaywall-left kernel: [ 9283.039041] NVRM: os_pci_init_handle: invalid context! Mar 11 18:51:46 displaywall-left kernel: [ 9283.039044] NVRM: os_pci_init_handle: invalid context! Mar 11 18:51:46 displaywall-left kernel: [ 9283.039047] NVRM: os_pci_init_handle: invalid context! Mar 11 18:51:46 displaywall-left kernel: [ 9283.039050] NVRM: os_pci_init_handle: invalid context! Mar 11 18:51:46 displaywall-left kernel: [ 9283.039053] NVRM: os_pci_init_handle: invalid context! Mar 11 18:51:46 displaywall-left kernel: [ 9283.039056] NVRM: os_pci_init_handle: invalid context! Mar 11 18:51:46 displaywall-left kernel: [ 9283.039060] NVRM: os_pci_init_handle: invalid context! Mar 11 18:51:46 displaywall-left kernel: [ 9283.039063] NVRM: os_pci_init_handle: invalid context! Mar 11 18:51:46 displaywall-left kernel: [ 9283.039066] NVRM: os_pci_init_handle: invalid context! Mar 11 18:51:46 displaywall-left kernel: [ 9283.039069] NVRM: os_pci_init_handle: invalid context! Mar 11 18:51:46 displaywall-left kernel: [ 9283.039075] NVRM: GPU at 0000:89:00: GPU-8ee5dde2-f438-9b90-7e76-4ac90149d186 Mar 11 18:51:46 displaywall-left kernel: [ 9283.039079] NVRM: Xid (0000:89:00): 31, Ch 00000003, engmask 00000111, intr 10000000 Mar 11 18:51:46 displaywall-left kernel: [ 9283.040473] NVRM: os_pci_init_handle: invalid context! Mar 11 18:51:46 displaywall-left kernel: [ 9283.040478] NVRM: os_pci_init_handle: invalid context! Mar 11 18:51:46 displaywall-left kernel: [ 9283.040482] NVRM: os_pci_init_handle: invalid context! Mar 11 18:51:46 displaywall-left kernel: [ 9283.040485] NVRM: os_pci_init_handle: invalid context! Mar 11 18:51:46 displaywall-left kernel: [ 9283.040488] NVRM: os_pci_init_handle: invalid context! Mar 11 18:51:46 displaywall-left kernel: [ 9283.040491] NVRM: os_pci_init_handle: invalid context! Mar 11 18:51:46 displaywall-left kernel: [ 9283.040494] NVRM: os_pci_init_handle: invalid context! Mar 11 18:51:46 displaywall-left kernel: [ 9283.040497] NVRM: os_pci_init_handle: invalid context! Mar 11 18:51:46 displaywall-left kernel: [ 9283.040501] NVRM: os_pci_init_handle: invalid context! Mar 11 18:51:46 displaywall-left kernel: [ 9283.040504] NVRM: os_pci_init_handle: invalid context! Mar 11 18:51:46 displaywall-left kernel: [ 9283.040507] NVRM: os_pci_init_handle: invalid context! Mar 11 18:51:46 displaywall-left kernel: [ 9283.040510] NVRM: os_pci_init_handle: invalid context! Mar 11 18:51:46 displaywall-left kernel: [ 9283.040513] NVRM: os_pci_init_handle: invalid context! Mar 11 18:51:46 displaywall-left kernel: [ 9283.040520] NVRM: Xid (0000:89:00): 13, 0003 00000000 0000902d 000002e0 00000000 00000000 Mar 11 18:52:16 displaywall-left kernel: [ 9312.352019] NVRM: Xid (0000:02:00): 61, 0096(1ee4) 00000000 00000000 Mar 11 18:52:16 displaywall-left kernel: [ 9312.356329] NVRM: Xid (0000:02:00): 61, 0096(1ef0) 00000000 00000000 Mar 11 18:52:16 displaywall-left kernel: [ 9312.356757] NVRM: Xid (0000:03:00): 61, 0096(1ee4) 00000000 00000000 Mar 11 18:52:16 displaywall-left kernel: [ 9312.671191] NVRM: Xid (0000:03:00): 61, 0096(1ef0) 00000000 00000000