Bug 358142

Summary:	Plasma crashes with nouveau driver
Product:	[Plasma] plasmashell	Reporter:	Cesko Voeten <cvoeten>
Component:	general	Assignee:	David Edmundson <kde>
Status:	RESOLVED DOWNSTREAM
Severity:	crash	CC:	alienisty, bhush94, pfeiffer, plasma-bugs, squan, un.tripudio.di.miccette
Priority:	NOR	Keywords:	drkonqi
Version:	5.5.3
Target Milestone:	1.0
Platform:	Compiled Sources
OS:	Linux
See Also:	https://bugs.kde.org/show_bug.cgi?id=365209
Latest Commit:		Version Fixed In:
Sentry Crash Report:

Description Cesko Voeten 2016-01-17 20:18:35 UTC

Application: plasmashell (5.5.3)
 (Compiled from sources)
Qt Version: 5.5.1
Operating System: Linux 4.4.0-gentoo x86_64
Distribution: "Gentoo Base System release 2.2"

-- Information about the crash:
- What I was doing when the application crashed:

Logging into the system.

- Unusual behavior I noticed:

If I use openbox as window manager as opposed to kwin, I can at least make it to the desktop (although with a few small kernel complaints; no stacktraces though) and the shell does not crash until I click the lower-left K launcher icon (replacing it with the 'Application menu' launcher allows me to launch applications without crashing the shell).

It is of extreme importance to note that there are massive complaints from the kernel during my failed attempt to log in. I'm unsure if these are the result of my issues (KDE supplying incorrect commands to the driver?) or the cause (driver itself broken)? It should be noted that other GL apps work completely fine with zero issues - e.g. GNOME 3, really any 3D game, KDE 4, etc.; this is why I did not immediately discount this issue as an upstream problem, but wanted to ask you guys first (and the stacktrace also says 'your kernel is fine' ;) ). See below:

[   88.010981] nouveau 0000:01:00.0: fifo: DMA_PUSHER - ch 4 [ksplashqml[538]] get 0020024b08 put 0020028a50 ib_get 00000022 ib_put 00000023 state 40000004 (err: INVALID_MTHD) push 00406040
[   88.011148] nouveau 0000:01:00.0: gr: DATA_ERROR 0000000c [INVALID_BITFIELD]                                                                                                                                                                                                
[   88.011157] nouveau 0000:01:00.0: gr: 00100000 [] ch 4 [001f935000 ksplashqml[538]] subc 3 class 8297 mthd 0da0 data 0004721c                                                                                                                                               
[   88.012372] nouveau 0000:01:00.0: fifo: CACHE_ERROR - ch 4 [ksplashqml[538]] subc 0 mthd 0000 data 04380000                                                                                                                                                                 
[   88.027726] nouveau 0000:01:00.0: fifo: DMA_PUSHER - ch 4 [ksplashqml[538]] get 00200298b8 put 002002d42c ib_get 00000028 ib_put 00000029 state 80000000 (err: INVALID_CMD) push 00406040                                                                                   
[   88.027887] nouveau 0000:01:00.0: gr: DATA_ERROR 00000004 [INVALID_VALUE]                                                                                                                                                                                                   
[   88.027901] nouveau 0000:01:00.0: gr: 00100000 [] ch 4 [001f935000 ksplashqml[538]] subc 3 class 8297 mthd 0e58 data 00146200                                                                                                                                               
[   88.044326] nouveau 0000:01:00.0: fifo: DMA_PUSHER - ch 4 [ksplashqml[538]] get 002002d8c8 put 0020031308 ib_get 0000002e ib_put 0000002f state 80006e2c (err: INVALID_CMD) push 00406040                                                                                   
[   88.044499] nouveau 0000:01:00.0: gr: DATA_ERROR 00000004 [INVALID_VALUE]                                                                                                                                                                                                   
[   88.044507] nouveau 0000:01:00.0: gr: 00100000 [] ch 4 [001f935000 ksplashqml[538]] subc 3 class 8297 mthd 0e28 data 0004721c                                                                                                                                               
[   88.146068] nouveau 0000:01:00.0: fifo: DMA_PUSHER - ch 4 [ksplashqml[538]] get 002003976c put 0020039864 ib_get 0000003c ib_put 0000003d state 8000a314 (err: INVALID_CMD) push 00406040                                                                                   
[   88.177723] nouveau 0000:01:00.0: fifo: DMA_PUSHER - ch 4 [ksplashqml[538]] get 002003ab6c put 002003c034 ib_get 00000040 ib_put 00000041 state 80008861 (err: INVALID_CMD) push 00406040                                                                                   
[   88.211021] nouveau 0000:01:00.0: fifo: DMA_PUSHER - ch 4 [ksplashqml[538]] get 002003d9d4 put 0020041de8 ib_get 00000046 ib_put 00000047 state 80007780 (err: INVALID_CMD) push 00406040                                                                                   
[   88.211192] nouveau 0000:01:00.0: gr: DATA_ERROR 0000000c [INVALID_BITFIELD]                                                                                                                                                                                                
[   88.211203] nouveau 0000:01:00.0: gr: 00100000 [] ch 4 [001f935000 ksplashqml[538]] subc 3 class 8297 mthd 153c data 00106d80                                                                                                                                               
[   88.227714] nouveau 0000:01:00.0: fifo: DMA_PUSHER - ch 4 [ksplashqml[538]] get 0020042844 put 0020046c80 ib_get 0000004e ib_put 0000004f state 80007220 (err: INVALID_CMD) push 00406040                                                                                   
[   88.244313] nouveau 0000:01:00.0: fifo: DMA_PUSHER - ch 4 [ksplashqml[538]] get 0020047960 put 002004c170 ib_get 00000054 ib_put 00000055 state 80007780 (err: INVALID_CMD) push 00406040                                                                                   
[   88.294545] nouveau 0000:01:00.0: fifo: DMA_PUSHER - ch 4 [ksplashqml[538]] get 0020053f0c put 0020056ed8 ib_get 00000065 ib_put 00000066 state 80006c08 (err: INVALID_CMD) push 00406040                                                                                   
[   88.294721] nouveau 0000:01:00.0: gr: DATA_ERROR 00000005 [INVALID_ENUM]                                                                                                                                                                                                    
[   88.294731] nouveau 0000:01:00.0: gr: 00100000 [] ch 4 [001f935000 ksplashqml[538]] subc 3 class 8297 mthd 12cc data 000000cf                                                                                                                                               
[   88.311083] nouveau 0000:01:00.0: fifo: DMA_PUSHER - ch 4 [ksplashqml[538]] get 0020057674 put 002005af48 ib_get 0000006b ib_put 0000006c state 40000004 (err: INVALID_MTHD) push 00406040                                                                                  
[   88.315358] nouveau 0000:01:00.0: fifo: CACHE_ERROR - ch 4 [ksplashqml[538]] subc 0 mthd 0000 data 04380000                                                                                                                                                                 
[   88.327538] QSGRenderThread[549]: segfault at 8 ip 00007f4b561ca448 sp 00007f4b421e6340 error 4 in libdrm_nouveau.so.2.0.0[7f4b561c6000+7000]                                                                                                                               
[  118.999314] nouveau 0000:01:00.0: fifo: DMA_PUSHER - ch 15 [plasmashell[618]] get 0020045378 put 002004b0bc ib_get 0000002a ib_put 0000002b state 80007acc (err: INVALID_CMD) push 00406040
[  118.999443] nouveau 0000:01:00.0: gr: DATA_ERROR 00000005 [INVALID_ENUM]                                                                                                                                                                                                    
[  118.999451] nouveau 0000:01:00.0: gr: 00100000 [] ch 15 [001e8d6000 plasmashell[618]] subc 3 class 8297 mthd 1ac8 data 0004a200                                                                                                                                             
[  119.012718] nouveau 0000:01:00.0: gr: magic set 0:                                                                                                                                                                                                                          
[  119.012726] nouveau 0000:01:00.0: gr:        00408904: 20097a01                                                                                                                                                                                                             
[  119.012730] nouveau 0000:01:00.0: gr:        00408908: 00000000                                                                                                                                                                                                             
[  119.012734] nouveau 0000:01:00.0: gr:        0040890c: 40000430                                                                                                                                                                                                             
[  119.012737] nouveau 0000:01:00.0: gr:        00408910: 00000000                                                                                                                                                                                                             
[  119.012743] nouveau 0000:01:00.0: gr: TRAP_TEXTURE - TP0: 00000003 [ FAULT]                                                                                                                                                                                                 
[  119.012747] nouveau 0000:01:00.0: gr: magic set 1:                                                                                                                                                                                                                          
[  119.012750] nouveau 0000:01:00.0: gr:        00409904: 20086901                                                                                                                                                                                                             
[  119.012754] nouveau 0000:01:00.0: gr:        00409908: 00000000                                                                                                                                                                                                             
[  119.012757] nouveau 0000:01:00.0: gr:        0040990c: 40000430                                                                                                                                                                                                             
[  119.012761] nouveau 0000:01:00.0: gr:        00409910: 00000000                                                                                                                                                                                                             
[  119.012765] nouveau 0000:01:00.0: gr: TRAP_TEXTURE - TP1: 00000003 [ FAULT]                                                                                                                                                                                                 
[  119.012772] nouveau 0000:01:00.0: gr: 00200000 [] ch 15 [001e8d6000 plasmashell[618]] subc 3 class 8297 mthd 0f04 data 00000000                                                                                                                                             
[  119.012785] nouveau 0000:01:00.0: fb: trapped read at 0000000000 on channel 15 [1e8d6000 plasmashell[618]] engine 00 [PGRAPH] client 0a [TEXTURE] subclient 00 [] reason 00000000 [PT_NOT_PRESENT]                                                                          
[  119.120288] nouveau 0000:01:00.0: gr: magic set 0:                                                                                                                                                                                                                          
[  119.120296] nouveau 0000:01:00.0: gr:        00408904: 20097b01                                                                                                                                                                                                             
[  119.120301] nouveau 0000:01:00.0: gr:        00408908: 00000000                                                                                                                                                                                                             
[  119.120305] nouveau 0000:01:00.0: gr:        0040890c: 40000430                                                                                                                                                                                                             
[  119.120309] nouveau 0000:01:00.0: gr:        00408910: 00000000                                                                                                                                                                                                             
[  119.120315] nouveau 0000:01:00.0: gr: TRAP_TEXTURE - TP0: 00000003 [ FAULT]                                                                                                                                                                                                 
[  119.120319] nouveau 0000:01:00.0: gr: magic set 1:                                                                                                                                                                                                                          
[  119.120323] nouveau 0000:01:00.0: gr:        00409904: 20092701                                                                                                                                                                                                             
[  119.120327] nouveau 0000:01:00.0: gr:        00409908: 00000000                                                                                                                                                                                                             
[  119.120331] nouveau 0000:01:00.0: gr:        0040990c: 40000430                                                                                                                                                                                                             
[  119.120334] nouveau 0000:01:00.0: gr:        00409910: 00000000                                                                                                                                                                                                             
[  119.120339] nouveau 0000:01:00.0: gr: TRAP_TEXTURE - TP1: 00000003 [ FAULT]                                                                                                                                                                                                 
[  119.120346] nouveau 0000:01:00.0: gr: 00200000 [] ch 15 [001e8d6000 plasmashell[618]] subc 3 class 8297 mthd 15e0 data 00000000                                                                                                                                             
[  119.120361] nouveau 0000:01:00.0: fb: trapped read at 0000000000 on channel 15 [1e8d6000 plasmashell[618]] engine 00 [PGRAPH] client 0a [TEXTURE] subclient 00 [] reason 00000000 [PT_NOT_PRESENT]                                                                          
[  119.153770] nouveau 0000:01:00.0: gr: magic set 0:                                                                                                                                                                                                                          
[  119.153776] nouveau 0000:01:00.0: gr:        00408904: 20093401                                                                                                                                                                                                             
[  119.153779] nouveau 0000:01:00.0: gr:        00408908: 00000000                                                                                                                                                                                                             
[  119.153782] nouveau 0000:01:00.0: gr:        0040890c: 40000430                                                                                                                                                                                                             
[  119.153785] nouveau 0000:01:00.0: gr:        00408910: 00000000                                                                                                                                                                                                             
[  119.153788] nouveau 0000:01:00.0: gr: TRAP_TEXTURE - TP0: 00000003 [ FAULT]                                                                                                                                                                                                 
[  119.153791] nouveau 0000:01:00.0: gr: magic set 1:                                                                                                                                                                                                                          
[  119.153793] nouveau 0000:01:00.0: gr:        00409904: 20096901                                                                                                                                                                                                             
[  119.153795] nouveau 0000:01:00.0: gr:        00409908: 00000000                                                                                                                                                                                                             
[  119.153798] nouveau 0000:01:00.0: gr:        0040990c: 40000430                                                                                                                                                                                                             
[  119.153800] nouveau 0000:01:00.0: gr:        00409910: 00000000                                                                                                                                                                                                             
[  119.153803] nouveau 0000:01:00.0: gr: TRAP_TEXTURE - TP1: 00000003 [ FAULT]                                                                                                                                                                                                 
[  119.153808] nouveau 0000:01:00.0: gr: 00200000 [] ch 15 [001e8d6000 plasmashell[618]] subc 3 class 8297 mthd 1298 data 00000004                                                                                                                                             
[  119.153820] nouveau 0000:01:00.0: fb: trapped read at 0000000000 on channel 15 [1e8d6000 plasmashell[618]] engine 00 [PGRAPH] client 0a [TEXTURE] subclient 00 [] reason 00000000 [PT_NOT_PRESENT]                                                                          
[  119.210493] nouveau 0000:01:00.0: fifo: DMA_PUSHER - ch 15 [plasmashell[618]] get 00200619a8 put 00200649b4 ib_get 0000003c ib_put 0000003d state 80007228 (err: INVALID_CMD) push 00406040                                                                                 
[  119.210511] nouveau 0000:01:00.0: gr: DATA_ERROR 0000000c [INVALID_BITFIELD]                                                                                                                                                                                                
[  119.210517] nouveau 0000:01:00.0: gr: 00100000 [] ch 15 [001e8d6000 plasmashell[618]] subc 3 class 8297 mthd 1224 data 0004721c                                                                                                                                             
[  126.633605] nouveau 0000:01:00.0: fifo: DMA_PUSHER - ch 19 [plasmashell[699]] get 002005b5f4 put 0020060f08 ib_get 00000046 ib_put 00000047 state 80007228 (err: INVALID_CMD) push 00406040                                                                                 
[  126.633622] nouveau 0000:01:00.0: gr: DATA_ERROR 0000000c [INVALID_BITFIELD]                                                                                                                                                                                                
[  126.633627] nouveau 0000:01:00.0: gr: 00100000 [] ch 19 [001e2e2000 plasmashell[699]] subc 3 class 8297 mthd 1224 data 07800000                                                                                                                                             
[  127.812467] resource sanity check: requesting [mem 0xf7f74000-0xf8073fff], which spans more than 0000:01:00.0 [mem 0xf6000000-0xf7ffffff 64bit]
[  127.812470] ------------[ cut here ]------------
[  127.812476] WARNING: CPU: 2 PID: 723 at arch/x86/mm/ioremap.c:198 __ioremap_caller+0x2d8/0x350()
[  127.812477] Info: mapping multiple BARs. Your kernel is fine.
[  127.812478] Modules linked in:
[  127.812478]  nouveau radeon wmi video i2c_algo_bit drm_kms_helper cfbfillrect syscopyarea cfbimgblt sysfillrect sysimgblt fb_sys_fops cfbcopyarea ttm drm r8169 mii vboxnetadp(O) vboxnetflt(O) vboxdrv(O) vhba(O)
[  127.812491] CPU: 2 PID: 723 Comm: plasmashell Tainted: P           O    4.4.0-gentoo #3
[  127.812492] Hardware name: Gigabyte Technology Co., Ltd. H55M-USB3/H55M-USB3, BIOS F12d 02/15/2011
[  127.812493]  ffffffff815cf684 ffffffff8123dece ffff8800914e7a30 ffffffff81042453
[  127.812494]  00000000f7f74000 ffff8800914e7a80 ffffc90006800000 0000000000100000
[  127.812496]  0000000000000000 ffffffff810424c7 ffffffff815d67a0 0000000000000018
[  127.812497] Call Trace:
[  127.812501]  [<ffffffff8123dece>] ? dump_stack+0x47/0x69
[  127.812504]  [<ffffffff81042453>] ? warn_slowpath_common+0x73/0xa0
[  127.812505]  [<ffffffff810424c7>] ? warn_slowpath_fmt+0x47/0x50
[  127.812507]  [<ffffffff81038a48>] ? __ioremap_caller+0x2d8/0x350
[  127.812523]  [<ffffffffa0310524>] ? nv50_instobj_boot+0x94/0xf0 [nouveau]
[  127.812533]  [<ffffffffa031046e>] ? nv50_instobj_acquire+0x3e/0x60 [nouveau]
[  127.812543]  [<ffffffffa030f6ee>] ? nvkm_instobj_acquire_slow+0xe/0x20 [nouveau]
[  127.812552]  [<ffffffffa030f9e2>] ? nvkm_instobj_new+0x52/0x140 [nouveau]
[  127.812558]  [<ffffffffa02d5f1c>] ? nvkm_memory_new+0x2c/0x50 [nouveau]
[  127.812568]  [<ffffffffa0313a0c>] ? nvkm_vm_get+0x15c/0x270 [nouveau]
[  127.812577]  [<ffffffffa0365bc4>] ? nouveau_bo_vma_add+0x24/0x80 [nouveau]
[  127.812584]  [<ffffffffa0375f08>] ? nouveau_channel_prep+0x1e8/0x2c0 [nouveau]
[  127.812592]  [<ffffffffa037602f>] ? nouveau_channel_new+0x4f/0x680 [nouveau]
[  127.812599]  [<ffffffffa0374d0b>] ? nouveau_abi16+0xab/0xe0 [nouveau]
[  127.812606]  [<ffffffffa0375213>] ? nouveau_abi16_ioctl_channel_alloc+0xd3/0x2d0 [nouveau]
[  127.812611]  [<ffffffffa009bb0c>] ? drm_ioctl+0x12c/0x4b0 [drm]
[  127.812618]  [<ffffffffa0375140>] ? nouveau_abi16_ioctl_setparam+0x10/0x10 [nouveau]
[  127.812626]  [<ffffffffa035f559>] ? nouveau_drm_ioctl+0x59/0xb0 [nouveau]
[  127.812628]  [<ffffffff81119d43>] ? do_vfs_ioctl+0x293/0x470
[  127.812630]  [<ffffffff81122d8b>] ? __fget+0x6b/0xb0
[  127.812631]  [<ffffffff81119f56>] ? SyS_ioctl+0x36/0x70
[  127.812633]  [<ffffffff814af117>] ? entry_SYSCALL_64_fastpath+0x12/0x6a
[  127.812634] ---[ end trace 4bc0aed896069a1a ]---
[  127.812661] BUG: unable to handle kernel paging request at ffffc90000930000
[  127.812673] IP: [<ffffffff812531fb>] iowrite32+0x2b/0x30
[  127.812678] PGD 13300c067 PUD 13300d067 PMD bab0d067 PTE 0
[  127.812684] Oops: 0002 [#1] PREEMPT SMP 
[  127.812689] Modules linked in: nouveau radeon wmi video i2c_algo_bit drm_kms_helper cfbfillrect syscopyarea cfbimgblt sysfillrect sysimgblt fb_sys_fops cfbcopyarea ttm drm r8169 mii vboxnetadp(O) vboxnetflt(O) vboxdrv(O) vhba(O)
[  127.812716] CPU: 2 PID: 723 Comm: plasmashell Tainted: P        W  O    4.4.0-gentoo #3
[  127.812720] Hardware name: Gigabyte Technology Co., Ltd. H55M-USB3/H55M-USB3, BIOS F12d 02/15/2011
[  127.812724] task: ffff880129a98a80 ti: ffff8800914e4000 task.ti: ffff8800914e4000
[  127.812728] RIP: 0010:[<ffffffff812531fb>]  [<ffffffff812531fb>] iowrite32+0x2b/0x30
[  127.812733] RSP: 0018:ffff8800914e7a10  EFLAGS: 00010292
[  127.812736] RAX: ffffffffa0396080 RBX: 0000000000010000 RCX: 0000000000000009
[  127.812739] RDX: ffffc90000930000 RSI: ffffc90000930000 RDI: 000000001df07301
[  127.812742] RBP: 000000001df07301 R08: 0000000000000100 R09: 000000001de7b000
[  127.812746] R10: ffffffffa0396d20 R11: 000000001de7b000 R12: 0000000000000000
[  127.812749] R13: 00000000000001a0 R14: 0000000000000200 R15: ffff8800b867c180
[  127.812752] FS:  00007fca61ebe840(0000) GS:ffff880137c80000(0000) knlGS:0000000000000000
[  127.812756] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  127.812761] CR2: ffffc90000930000 CR3: 0000000097351000 CR4: 00000000000006e0
[  127.812764] Stack:
[  127.812766]  ffffffffa0314bfc 000000001df47001 ffff8800a6efa5b8 00000000810424c7
[  127.812772]  0000000000000000 ffff880126112b00 0000000000000100 0000000000000000
[  127.812778]  0000000000002074 ffff8800bb0f7a00 0000000000000000 ffff8800a6efa5b8
[  127.812784] Call Trace:
[  127.812795]  [<ffffffffa0314bfc>] ? nv50_vm_map+0x15c/0x1a0 [nouveau]
[  127.812808]  [<ffffffffa0312f2d>] ? nvkm_vm_map_at+0xcd/0x1d0 [nouveau]
[  127.812820]  [<ffffffffa031053a>] ? nv50_instobj_boot+0xaa/0xf0 [nouveau]
[  127.812832]  [<ffffffffa031046e>] ? nv50_instobj_acquire+0x3e/0x60 [nouveau]
[  127.812844]  [<ffffffffa030f6ee>] ? nvkm_instobj_acquire_slow+0xe/0x20 [nouveau]
[  127.812857]  [<ffffffffa030f9e2>] ? nvkm_instobj_new+0x52/0x140 [nouveau]
[  127.812865]  [<ffffffffa02d5f1c>] ? nvkm_memory_new+0x2c/0x50 [nouveau]
[  127.812877]  [<ffffffffa0313a0c>] ? nvkm_vm_get+0x15c/0x270 [nouveau]
[  127.812888]  [<ffffffffa0365bc4>] ? nouveau_bo_vma_add+0x24/0x80 [nouveau]
[  127.812898]  [<ffffffffa0375f08>] ? nouveau_channel_prep+0x1e8/0x2c0 [nouveau]
[  127.812908]  [<ffffffffa037602f>] ? nouveau_channel_new+0x4f/0x680 [nouveau]
[  127.812918]  [<ffffffffa0374d0b>] ? nouveau_abi16+0xab/0xe0 [nouveau]
[  127.812927]  [<ffffffffa0375213>] ? nouveau_abi16_ioctl_channel_alloc+0xd3/0x2d0 [nouveau]
[  127.812934]  [<ffffffffa009bb0c>] ? drm_ioctl+0x12c/0x4b0 [drm]
[  127.812943]  [<ffffffffa0375140>] ? nouveau_abi16_ioctl_setparam+0x10/0x10 [nouveau]
[  127.812954]  [<ffffffffa035f559>] ? nouveau_drm_ioctl+0x59/0xb0 [nouveau]
[  127.812958]  [<ffffffff81119d43>] ? do_vfs_ioctl+0x293/0x470
[  127.812961]  [<ffffffff81122d8b>] ? __fget+0x6b/0xb0
[  127.812964]  [<ffffffff81119f56>] ? SyS_ioctl+0x36/0x70
[  127.812968]  [<ffffffff814af117>] ? entry_SYSCALL_64_fastpath+0x12/0x6a
[  127.812971] Code: 48 89 f2 48 81 fe ff ff 03 00 77 1f 48 81 fe 00 00 01 00 76 07 0f b7 d6 89 f8 ef c3 48 c7 c6 8b 1f 5f 81 48 89 d7 e9 85 fe ff ff <89> 3e c3 66 90 48 81 ff ff ff 03 00 77 28 48 81 ff 00 00 01 00 
[  127.813029] RIP  [<ffffffff812531fb>] iowrite32+0x2b/0x30
[  127.813033]  RSP <ffff8800914e7a10>
[  127.813035] CR2: ffffc90000930000
[  127.816535] ---[ end trace 4bc0aed896069a1b ]---

The card is a:

01:00.0 VGA compatible controller [0300]: NVIDIA Corporation G84 [GeForce 8600 GT] [10de:0401] (rev a1) (prog-if 00 [VGA controller])

running on an ~amd64 Gentoo.

Let me know if you don't think this is your bug, but then I would kindly ask you to point me in the right direction where I might report it instead (mesa guys? libdrm guys?).

The crash can be reproduced every time.

-- Backtrace:
Application: Plasma (plasmashell), signal: Segmentation fault
Using host libthread_db library "/lib64/libthread_db.so.1".
pthread_cond_wait () at ../sysdeps/unix/sysv/linux/x86_64/pthread_cond_wait.S:185
[Current thread is 1 (Thread 0x7faa55f73840 (LWP 618))]

Thread 10 (Thread 0x7faa417db700 (LWP 620)):
#0  0x00007faa4f5ef32d in poll () at ../sysdeps/unix/syscall-template.S:84
#1  0x00007faa543d3ac2 in poll (__timeout=-1, __nfds=1, __fds=0x7faa417dac80) at /usr/include/bits/poll2.h:46
#2  _xcb_conn_wait (c=c@entry=0xdb9e90, cond=cond@entry=0xdb9ed0, vector=vector@entry=0x0, count=count@entry=0x0) at /var/tmp/portage/x11-libs/libxcb-1.11.1/work/libxcb-1.11.1/src/xcb_conn.c:459
#3  0x00007faa543d572f in xcb_wait_for_event (c=0xdb9e90) at /var/tmp/portage/x11-libs/libxcb-1.11.1/work/libxcb-1.11.1/src/xcb_in.c:693
#4  0x00007faa437336a9 in QXcbEventReader::run (this=0xdb8900) at qxcbconnection.cpp:1229
#5  0x00007faa4fcc9b52 in QThreadPrivate::start (arg=0xdb8900) at thread/qthread_unix.cpp:331
#6  0x00007faa4edf8444 in start_thread (arg=0x7faa417db700) at pthread_create.c:334
#7  0x00007faa4f5f830d in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:109

Thread 9 (Thread 0x7faa30625700 (LWP 671)):
#0  0x00007faa4f5eb2fd in read () at ../sysdeps/unix/syscall-template.S:84
#1  0x00007faa4bb74fe0 in read (__nbytes=16, __buf=0x7faa30624b60, __fd=<optimized out>) at /usr/include/bits/unistd.h:44
#2  g_wakeup_acknowledge (wakeup=0x7faa3c0015b0) at /var/tmp/portage/dev-libs/glib-2.46.2-r1/work/glib-2.46.2/glib/gwakeup.c:210
#3  0x00007faa4bb319d4 in g_main_context_check (context=context@entry=0x7faa28000990, max_priority=2147483647, fds=fds@entry=0x7faa28003070, n_fds=n_fds@entry=1) at /var/tmp/portage/dev-libs/glib-2.46.2-r1/work/glib-2.46.2/glib/gmain.c:3632
#4  0x00007faa4bb31e90 in g_main_context_iterate (context=context@entry=0x7faa28000990, block=block@entry=1, dispatch=dispatch@entry=1, self=<optimized out>) at /var/tmp/portage/dev-libs/glib-2.46.2-r1/work/glib-2.46.2/glib/gmain.c:3837
#5  0x00007faa4bb31ffc in g_main_context_iteration (context=0x7faa28000990, may_block=may_block@entry=1) at /var/tmp/portage/dev-libs/glib-2.46.2-r1/work/glib-2.46.2/glib/gmain.c:3901
#6  0x00007faa4feb56cb in QEventDispatcherGlib::processEvents (this=0x7faa280008c0, flags=...) at kernel/qeventdispatcher_glib.cpp:420
#7  0x00007faa4fe680ea in QEventLoop::exec (this=this@entry=0x7faa30624d60, flags=..., flags@entry=...) at kernel/qeventloop.cpp:204
#8  0x00007faa4fcc5624 in QThread::exec (this=this@entry=0xf025d0) at thread/qthread.cpp:503
#9  0x00007faa52ea87e5 in QQmlThreadPrivate::run (this=0xf025d0) at qml/ftw/qqmlthread.cpp:141
#10 0x00007faa4fcc9b52 in QThreadPrivate::start (arg=0xf025d0) at thread/qthread_unix.cpp:331
#11 0x00007faa4edf8444 in start_thread (arg=0x7faa30625700) at pthread_create.c:334
#12 0x00007faa4f5f830d in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:109

Thread 8 (Thread 0x7faa25a17700 (LWP 676)):
#0  g_main_context_iterate (context=context@entry=0x7faa20000990, block=block@entry=1, dispatch=dispatch@entry=1, self=<optimized out>) at /var/tmp/portage/dev-libs/glib-2.46.2-r1/work/glib-2.46.2/glib/gmain.c:3847
#1  0x00007faa4bb31ffc in g_main_context_iteration (context=0x7faa20000990, may_block=may_block@entry=1) at /var/tmp/portage/dev-libs/glib-2.46.2-r1/work/glib-2.46.2/glib/gmain.c:3901
#2  0x00007faa4feb56cb in QEventDispatcherGlib::processEvents (this=0x7faa200008c0, flags=...) at kernel/qeventdispatcher_glib.cpp:420
#3  0x00007faa4fe680ea in QEventLoop::exec (this=this@entry=0x7faa25a16d60, flags=..., flags@entry=...) at kernel/qeventloop.cpp:204
#4  0x00007faa4fcc5624 in QThread::exec (this=this@entry=0x1455150) at thread/qthread.cpp:503
#5  0x00007faa52ea87e5 in QQmlThreadPrivate::run (this=0x1455150) at qml/ftw/qqmlthread.cpp:141
#6  0x00007faa4fcc9b52 in QThreadPrivate::start (arg=0x1455150) at thread/qthread_unix.cpp:331
#7  0x00007faa4edf8444 in start_thread (arg=0x7faa25a17700) at pthread_create.c:334
#8  0x00007faa4f5f830d in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:109

Thread 7 (Thread 0x7faa1f9b3700 (LWP 677)):
#0  0x00007faa4feb6017 in timerSourceCheck (source=0x7faa18002e70) at kernel/qeventdispatcher_glib.cpp:166
#1  0x00007faa4bb31921 in g_main_context_check (context=context@entry=0x7faa18000990, max_priority=2147483647, fds=fds@entry=0x7faa18003070, n_fds=n_fds@entry=1) at /var/tmp/portage/dev-libs/glib-2.46.2-r1/work/glib-2.46.2/glib/gmain.c:3681
#2  0x00007faa4bb31e90 in g_main_context_iterate (context=context@entry=0x7faa18000990, block=block@entry=1, dispatch=dispatch@entry=1, self=<optimized out>) at /var/tmp/portage/dev-libs/glib-2.46.2-r1/work/glib-2.46.2/glib/gmain.c:3837
#3  0x00007faa4bb31ffc in g_main_context_iteration (context=0x7faa18000990, may_block=may_block@entry=1) at /var/tmp/portage/dev-libs/glib-2.46.2-r1/work/glib-2.46.2/glib/gmain.c:3901
#4  0x00007faa4feb56cb in QEventDispatcherGlib::processEvents (this=0x7faa180008c0, flags=...) at kernel/qeventdispatcher_glib.cpp:420
#5  0x00007faa4fe680ea in QEventLoop::exec (this=this@entry=0x7faa1f9b2d60, flags=..., flags@entry=...) at kernel/qeventloop.cpp:204
#6  0x00007faa4fcc5624 in QThread::exec (this=this@entry=0x113db90) at thread/qthread.cpp:503
#7  0x00007faa52ea87e5 in QQmlThreadPrivate::run (this=0x113db90) at qml/ftw/qqmlthread.cpp:141
#8  0x00007faa4fcc9b52 in QThreadPrivate::start (arg=0x113db90) at thread/qthread_unix.cpp:331
#9  0x00007faa4edf8444 in start_thread (arg=0x7faa1f9b3700) at pthread_create.c:334
#10 0x00007faa4f5f830d in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:109

Thread 6 (Thread 0x7faa1e09b700 (LWP 686)):
#0  pthread_cond_wait () at ../sysdeps/unix/sysv/linux/x86_64/pthread_cond_wait.S:185
#1  0x00007faa5565f584 in QTWTF::TCMalloc_PageHeap::scavengerThread (this=0x7faa55946ea0 <QTWTF::pageheap_memory>) at ../3rdparty/javascriptcore/JavaScriptCore/wtf/FastMalloc.cpp:2359
#2  0x00007faa5565f5c9 in QTWTF::TCMalloc_PageHeap::runScavengerThread (context=<optimized out>) at ../3rdparty/javascriptcore/JavaScriptCore/wtf/FastMalloc.cpp:1464
#3  0x00007faa4edf8444 in start_thread (arg=0x7faa1e09b700) at pthread_create.c:334
#4  0x00007faa4f5f830d in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:109

Thread 5 (Thread 0x7fa997063700 (LWP 689)):
#0  0x00007faa4f5ef32d in poll () at ../sysdeps/unix/syscall-template.S:84
#1  0x00007faa4bb31eec in g_main_context_poll (priority=2147483647, n_fds=1, fds=0x7fa990003120, timeout=<optimized out>, context=0x7fa990000990) at /var/tmp/portage/dev-libs/glib-2.46.2-r1/work/glib-2.46.2/glib/gmain.c:4135
#2  g_main_context_iterate (context=context@entry=0x7fa990000990, block=block@entry=1, dispatch=dispatch@entry=1, self=<optimized out>) at /var/tmp/portage/dev-libs/glib-2.46.2-r1/work/glib-2.46.2/glib/gmain.c:3835
#3  0x00007faa4bb31ffc in g_main_context_iteration (context=0x7fa990000990, may_block=may_block@entry=1) at /var/tmp/portage/dev-libs/glib-2.46.2-r1/work/glib-2.46.2/glib/gmain.c:3901
#4  0x00007faa4feb56cb in QEventDispatcherGlib::processEvents (this=0x7fa9900008c0, flags=...) at kernel/qeventdispatcher_glib.cpp:420
#5  0x00007faa4fe680ea in QEventLoop::exec (this=this@entry=0x7fa997062d10, flags=..., flags@entry=...) at kernel/qeventloop.cpp:204
#6  0x00007faa4fcc5624 in QThread::exec (this=this@entry=0x11c7e90) at thread/qthread.cpp:503
#7  0x00007faa53a2c706 in QQuickPixmapReader::run (this=0x11c7e90) at util/qquickpixmapcache.cpp:760
#8  0x00007faa4fcc9b52 in QThreadPrivate::start (arg=0x11c7e90) at thread/qthread_unix.cpp:331
#9  0x00007faa4edf8444 in start_thread (arg=0x7fa997063700) at pthread_create.c:334
#10 0x00007faa4f5f830d in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:109

Thread 4 (Thread 0x7fa996078700 (LWP 690)):
#0  pthread_cond_wait () at ../sysdeps/unix/sysv/linux/x86_64/pthread_cond_wait.S:185
#1  0x00007faa4fcca1ba in QWaitConditionPrivate::wait (time=18446744073709551615, this=0x152c370) at thread/qwaitcondition_unix.cpp:136
#2  QWaitCondition::wait (this=this@entry=0x134f788, mutex=mutex@entry=0x134f780, time=time@entry=18446744073709551615) at thread/qwaitcondition_unix.cpp:208
#3  0x00007faa53aa123e in QSGRenderThreadEventQueue::takeEvent (wait=true, this=0x134f778) at scenegraph/qsgthreadedrenderloop.cpp:224
#4  QSGRenderThread::processEventsAndWaitForMore (this=this@entry=0x134f700) at scenegraph/qsgthreadedrenderloop.cpp:657
#5  0x00007faa53aa1ac3 in QSGRenderThread::run (this=0x134f700) at scenegraph/qsgthreadedrenderloop.cpp:686
#6  0x00007faa4fcc9b52 in QThreadPrivate::start (arg=0x134f700) at thread/qthread_unix.cpp:331
#7  0x00007faa4edf8444 in start_thread (arg=0x7fa996078700) at pthread_create.c:334
#8  0x00007faa4f5f830d in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:109

Thread 3 (Thread 0x7fa983000700 (LWP 696)):
#0  pushbuf_flush (push=push@entry=0xe06cd0) at /var/tmp/portage/x11-libs/libdrm-2.4.66/work/libdrm-2.4.66/nouveau/pushbuf.c:430
#1  0x00007faa3a7fde00 in nouveau_pushbuf_kick (push=0xe06cd0, chan=<optimized out>) at /var/tmp/portage/x11-libs/libdrm-2.4.66/work/libdrm-2.4.66/nouveau/pushbuf.c:779
#2  0x00007faa3b0c4d06 in PUSH_KICK (push=<optimized out>) at /var/tmp/portage/media-libs/mesa-11.1.1/work/mesa-11.1.1/src/gallium/drivers/nouveau/nouveau_winsys.h:58
#3  nv50_flush (pipe=0x24eeb90, fence=<optimized out>, flags=<optimized out>) at /var/tmp/portage/media-libs/mesa-11.1.1/work/mesa-11.1.1/src/gallium/drivers/nouveau/nv50/nv50_context.c:40
#4  0x00007faa3ae4581a in st_context_flush (stctxi=0x25304e0, flags=2, fence=<optimized out>) at /var/tmp/portage/media-libs/mesa-11.1.1/work/mesa-11.1.1/src/mesa/state_tracker/st_manager.c:504
#5  0x00007faa3af1baf9 in dri_flush (cPriv=<optimized out>, dPriv=<optimized out>, flags=<optimized out>, reason=<optimized out>) at /var/tmp/portage/media-libs/mesa-11.1.1/work/mesa-11.1.1/src/gallium/state_trackers/dri/dri_drawable.c:530
#6  0x00007faa40597a98 in dri2_x11_swap_buffers_msc (msc=0, divisor=0, remainder=0, drv=<optimized out>, draw=0x1227680, disp=<optimized out>) at /var/tmp/portage/media-libs/mesa-11.1.1/work/mesa-11.1.1/src/egl/drivers/dri2/platform_x11.c:837
#7  dri2_x11_swap_buffers (drv=<optimized out>, disp=<optimized out>, draw=0x1227680) at /var/tmp/portage/media-libs/mesa-11.1.1/work/mesa-11.1.1/src/egl/drivers/dri2/platform_x11.c:873
#8  0x00007faa4058d826 in eglSwapBuffers (dpy=0xe06250, surface=<optimized out>) at /var/tmp/portage/media-libs/mesa-11.1.1/work/mesa-11.1.1/src/egl/main/eglapi.c:1010
#9  0x00007faa407ba791 in QEGLPlatformContext::swapBuffers (this=0x24e6610, surface=0x12ede90) at eglconvenience/qeglplatformcontext.cpp:410
#10 0x00007faa503b3486 in QOpenGLContext::swapBuffers (this=0x24ec710, surface=<optimized out>) at kernel/qopenglcontext.cpp:1025
#11 0x00007faa53a9c6f9 in QSGRenderThread::syncAndRender (this=this@entry=0x24ee8c0) at scenegraph/qsgthreadedrenderloop.cpp:601
#12 0x00007faa53aa199c in QSGRenderThread::run (this=0x24ee8c0) at scenegraph/qsgthreadedrenderloop.cpp:677
#13 0x00007faa4fcc9b52 in QThreadPrivate::start (arg=0x24ee8c0) at thread/qthread_unix.cpp:331
#14 0x00007faa4edf8444 in start_thread (arg=0x7fa983000700) at pthread_create.c:334
#15 0x00007faa4f5f830d in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:109

Thread 2 (Thread 0x7fa9827ff700 (LWP 697)):
[KCrash Handler]
#6  0x00007faa3a7fd448 in pushbuf_kref (push=push@entry=0xe06cd0, bo=0x0, flags=0) at /var/tmp/portage/x11-libs/libdrm-2.4.66/work/libdrm-2.4.66/nouveau/pushbuf.c:167
#7  0x00007faa3a7fdb09 in pushbuf_validate (push=0xe06cd0, retry=<optimized out>) at /var/tmp/portage/x11-libs/libdrm-2.4.66/work/libdrm-2.4.66/nouveau/pushbuf.c:506
#8  0x00007faa3a7fdd7a in nouveau_pushbuf_validate (push=<optimized out>) at /var/tmp/portage/x11-libs/libdrm-2.4.66/work/libdrm-2.4.66/nouveau/pushbuf.c:753
#9  0x00007faa3b0d3bdb in nv50_state_validate (nv50=nv50@entry=0x25d9920, mask=mask@entry=4294967295, words=words@entry=8) at /var/tmp/portage/media-libs/mesa-11.1.1/work/mesa-11.1.1/src/gallium/drivers/nouveau/nv50/nv50_state_validate.c:541
#10 0x00007faa3b0e18e6 in nv50_draw_vbo (pipe=0x25d9920, info=0x7fa9827fe520) at /var/tmp/portage/media-libs/mesa-11.1.1/work/mesa-11.1.1/src/gallium/drivers/nouveau/nv50/nv50_vbo.c:790
#11 0x00007faa3ae1516f in st_draw_vbo (ctx=0x25dac10, prims=0x7fa9827fe600, nr_prims=1, ib=0x7fa9827fe5e0, index_bounds_valid=<optimized out>, min_index=4294967295, max_index=4294967295, tfb_vertcount=0x0, stream=0, indirect=0x0) at /var/tmp/portage/media-libs/mesa-11.1.1/work/mesa-11.1.1/src/mesa/state_tracker/st_draw.c:291
#12 0x00007faa3ade5188 in vbo_validated_drawrangeelements (ctx=ctx@entry=0x25dac10, mode=mode@entry=5, index_bounds_valid=index_bounds_valid@entry=0 '\000', start=start@entry=4294967295, end=end@entry=4294967295, count=count@entry=4, type=5123, indices=0x7fa9740645b2, basevertex=0, numInstances=1, baseInstance=0) at /var/tmp/portage/media-libs/mesa-11.1.1/work/mesa-11.1.1/src/mesa/vbo/vbo_exec_array.c:992
#13 0x00007faa3ade5609 in vbo_exec_DrawElements (mode=5, count=4, type=5123, indices=0x7fa9740645b2) at /var/tmp/portage/media-libs/mesa-11.1.1/work/mesa-11.1.1/src/mesa/vbo/vbo_exec_array.c:1128
#14 0x00007faa53a5bdd5 in QOpenGLFunctions::glDrawElements (this=0x7fa9740048a8, indices=<optimized out>, type=5123, count=<optimized out>, mode=<optimized out>) at /usr/include/qt5/QtGui/qopenglfunctions.h:724
#15 QSGBatchRenderer::Renderer::renderMergedBatch (this=0x7fa9740047d0, batch=0x7fa9740e8280) at scenegraph/coreapi/qsgbatchrenderer.cpp:2299
#16 0x00007faa53a5c6ad in QSGBatchRenderer::Renderer::renderBatches (this=this@entry=0x7fa9740047d0) at scenegraph/coreapi/qsgbatchrenderer.cpp:2508
#17 0x00007faa53a61e22 in QSGBatchRenderer::Renderer::render (this=<optimized out>) at scenegraph/coreapi/qsgbatchrenderer.cpp:2681
#18 0x00007faa53a6db2f in QSGRenderer::renderScene (this=0x7fa9740047d0, bindable=...) at scenegraph/coreapi/qsgrenderer.cpp:208
#19 0x00007faa53a6e37b in QSGRenderer::renderScene (this=<optimized out>, fboId=<optimized out>) at scenegraph/coreapi/qsgrenderer.cpp:168
#20 0x00007faa53a7e5ee in QSGRenderContext::renderNextFrame (this=0x1aa5030, renderer=0x7fa9740047d0, fboId=<optimized out>) at scenegraph/qsgcontext.cpp:558
#21 0x00007faa53ac804b in QQuickWindowPrivate::renderSceneGraph (this=this@entry=0x1a9ecb0, size=...) at items/qquickwindow.cpp:383
#22 0x00007faa53a9c2d8 in QSGRenderThread::syncAndRender (this=this@entry=0x25c0210) at scenegraph/qsgthreadedrenderloop.cpp:596
#23 0x00007faa53aa199c in QSGRenderThread::run (this=0x25c0210) at scenegraph/qsgthreadedrenderloop.cpp:677
#24 0x00007faa4fcc9b52 in QThreadPrivate::start (arg=0x25c0210) at thread/qthread_unix.cpp:331
#25 0x00007faa4edf8444 in start_thread (arg=0x7fa9827ff700) at pthread_create.c:334
#26 0x00007faa4f5f830d in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:109

Thread 1 (Thread 0x7faa55f73840 (LWP 618)):
#0  pthread_cond_wait () at ../sysdeps/unix/sysv/linux/x86_64/pthread_cond_wait.S:185
#1  0x00007faa4fcca1ba in QWaitConditionPrivate::wait (time=18446744073709551615, this=0x24edb10) at thread/qwaitcondition_unix.cpp:136
#2  QWaitCondition::wait (this=<optimized out>, mutex=0x24ee900, time=time@entry=18446744073709551615) at thread/qwaitcondition_unix.cpp:208
#3  0x00007faa53a9e4d6 in QSGThreadedRenderLoop::polishAndSync (this=this@entry=0xfac550, w=<optimized out>, inExpose=inExpose@entry=false) at scenegraph/qsgthreadedrenderloop.cpp:1150
#4  0x00007faa53a9eeb2 in QSGThreadedRenderLoop::handleUpdateRequest (this=0xfac550, window=0x11956f0) at scenegraph/qsgthreadedrenderloop.cpp:977
#5  0x00007faa53ad3817 in QQuickWindow::event (this=this@entry=0x11956f0, e=e@entry=0x7ffe12977ea0) at items/qquickwindow.cpp:1400
#6  0x000000000044404b in PanelView::event (this=0x11956f0, e=0x7ffe12977ea0) at /var/tmp/portage/kde-plasma/plasma-workspace-5.5.3/work/plasma-workspace-5.5.3/shell/panelview.cpp:844
#7  0x00007faa510dc4bc in QApplicationPrivate::notify_helper (this=this@entry=0xdad540, receiver=receiver@entry=0x11956f0, e=e@entry=0x7ffe12977ea0) at kernel/qapplication.cpp:3716
#8  0x00007faa510e1986 in QApplication::notify (this=0x7ffe12978620, receiver=0x11956f0, e=0x7ffe12977ea0) at kernel/qapplication.cpp:3499
#9  0x00007faa4fe691dd in QCoreApplication::notifyInternal (this=0x7ffe12978620, receiver=receiver@entry=0x11956f0, event=event@entry=0x7ffe12977ea0) at kernel/qcoreapplication.cpp:965
#10 0x00007faa5038bcd0 in QCoreApplication::sendEvent (event=0x7ffe12977ea0, receiver=<optimized out>) at ../../include/QtCore/../../src/corelib/kernel/qcoreapplication.h:224
#11 QWindowPrivate::deliverUpdateRequest (this=this@entry=0x14755f0) at kernel/qwindow.cpp:2081
#12 0x00007faa5038c209 in QWindow::event (this=this@entry=0x11956f0, ev=ev@entry=0x7ffe12978280) at kernel/qwindow.cpp:2063
#13 0x00007faa53ad3831 in QQuickWindow::event (this=this@entry=0x11956f0, e=e@entry=0x7ffe12978280) at items/qquickwindow.cpp:1413
#14 0x000000000044404b in PanelView::event (this=0x11956f0, e=0x7ffe12978280) at /var/tmp/portage/kde-plasma/plasma-workspace-5.5.3/work/plasma-workspace-5.5.3/shell/panelview.cpp:844
#15 0x00007faa510dc4bc in QApplicationPrivate::notify_helper (this=this@entry=0xdad540, receiver=receiver@entry=0x11956f0, e=e@entry=0x7ffe12978280) at kernel/qapplication.cpp:3716
#16 0x00007faa510e1986 in QApplication::notify (this=0x7ffe12978620, receiver=0x11956f0, e=0x7ffe12978280) at kernel/qapplication.cpp:3499
#17 0x00007faa4fe691dd in QCoreApplication::notifyInternal (this=0x7ffe12978620, receiver=0x11956f0, event=event@entry=0x7ffe12978280) at kernel/qcoreapplication.cpp:965
#18 0x00007faa4feb4d5a in QCoreApplication::sendEvent (event=0x7ffe12978280, receiver=<optimized out>) at ../../include/QtCore/../../src/corelib/kernel/qcoreapplication.h:224
#19 QTimerInfoList::activateTimers (this=0xe67660) at kernel/qtimerinfo_unix.cpp:637
#20 0x00007faa4feb52c1 in timerSourceDispatch (source=<optimized out>) at kernel/qeventdispatcher_glib.cpp:177
#21 0x00007faa4bb31cf7 in g_main_dispatch (context=0x7faa3c0016f0) at /var/tmp/portage/dev-libs/glib-2.46.2-r1/work/glib-2.46.2/glib/gmain.c:3154
#22 g_main_context_dispatch (context=context@entry=0x7faa3c0016f0) at /var/tmp/portage/dev-libs/glib-2.46.2-r1/work/glib-2.46.2/glib/gmain.c:3769
#23 0x00007faa4bb31f50 in g_main_context_iterate (context=context@entry=0x7faa3c0016f0, block=block@entry=1, dispatch=dispatch@entry=1, self=<optimized out>) at /var/tmp/portage/dev-libs/glib-2.46.2-r1/work/glib-2.46.2/glib/gmain.c:3840
#24 0x00007faa4bb31ffc in g_main_context_iteration (context=0x7faa3c0016f0, may_block=may_block@entry=1) at /var/tmp/portage/dev-libs/glib-2.46.2-r1/work/glib-2.46.2/glib/gmain.c:3901
#25 0x00007faa4feb56af in QEventDispatcherGlib::processEvents (this=0xe64790, flags=...) at kernel/qeventdispatcher_glib.cpp:418
#26 0x00007faa4fe680ea in QEventLoop::exec (this=this@entry=0x7ffe129784c0, flags=..., flags@entry=...) at kernel/qeventloop.cpp:204
#27 0x00007faa4fe6f18c in QCoreApplication::exec () at kernel/qcoreapplication.cpp:1229
#28 0x00007faa5037ab2c in QGuiApplication::exec () at kernel/qguiapplication.cpp:1527
#29 0x00007faa510d88f5 in QApplication::exec () at kernel/qapplication.cpp:2976
#30 0x000000000043228a in main (argc=2, argv=<optimized out>) at /var/tmp/portage/kde-plasma/plasma-workspace-5.5.3/work/plasma-workspace-5.5.3/shell/main.cpp:179

Reported using DrKonqi

Comment 1 Marco Martin 2016-07-21 12:36:04 UTC

*** Bug 365767 has been marked as a duplicate of this bug. ***

Comment 2 Marco Martin 2016-08-18 15:04:54 UTC

*** Bug 367081 has been marked as a duplicate of this bug. ***

Comment 3 David Edmundson 2016-10-09 22:39:57 UTC

Can you forward this to the Mesa guys please.

Comment 4 David Edmundson 2016-10-09 22:40:30 UTC

Also you might find (if this is happening often) running 

QSG_RENDER_LOOP=basic plasmashell

won't crash

Comment 5 Christoph Feck 2017-01-25 00:30:28 UTC

Crash is in the nouveau drivers. If this is still happening with a recent driver version, please report this issue directly to nouveau developers via https://bugs.freedesktop.org/