我在使用 Ubuntu 16.04 时遇到了问题。几个小时不活动后（例如一整夜），系统被锁定。屏幕保持关闭状态，但计算机仍在继续工作。例如，媒体播放器正在播放音乐。但屏幕关闭了，我无法解锁系统。
系统配置：
- 主板华硕 Sabertooth Mark 1
- CPU 英特尔酷睿 I7-4790
- 内存 DDR3 16GB
- 显卡 Radeon R9-270 1GB
- 硬盘：Corsair SSD 120GB
- 键盘和鼠标 - 无线 USB，在 DOS 下工作，无需驱动程序
- 操作系统：Ubuntu 16.04.01 x64
我在我的系统日志文件中看到这个错误：
Aug 24 10:50:56 default kernel: [36130.934868] amdgpu 0000:01:00.0: GPU fault detected: 146 0x0bb8440c
Aug 24 10:50:56 default kernel: [36130.934871] amdgpu 0000:01:00.0: VM_CONTEXT1_PROTECTION_FAULT_ADDR 0x00114177
Aug 24 10:50:56 default kernel: [36130.934872] amdgpu 0000:01:00.0: VM_CONTEXT1_PROTECTION_FAULT_STATUS 0x0804400C
Aug 24 10:50:56 default kernel: [36130.934873] VM fault (0x0c, vmid 4) at page 1130871, read from 'TC7' (0x54433700) (68)
在此之后，我反复看到（10次）：
Aug 24 10:54:49 default kernel: [36363.986009] INFO: task Xorg:12385 blocked for more than 120 seconds.
Aug 24 10:54:49 default kernel: [36363.986017] Not tainted 4.4.0-34-generic #53-Ubuntu
Aug 24 10:54:49 default kernel: [36363.986020] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
Aug 24 10:54:49 default kernel: [36363.986025] Xorg D ffff88042a3c39d0 0 12385 3116 0x00400004
Aug 24 10:54:49 default kernel: [36363.986033] ffff88042a3c39d0 ffff88042a3c39b0 ffff88042c708dc0 ffff8803b6b40dc0
Aug 24 10:54:49 default kernel: [36363.986040] ffff88042a3c4000 ffff88002b5b4060 ffff880426bde1c8 ffffffffc021b230
Aug 24 10:54:49 default kernel: [36363.986045] ffff880426bd8000 ffff88042a3c39e8 ffffffff81829e15 0000000000000000
Aug 24 10:54:49 default kernel: [36363.986051] Call Trace:
Aug 24 10:54:49 default kernel: [36363.986115] [<ffffffffc021b230>] ? amdgpu_gem_prime_export+0x50/0x50 [amdgpu]
Aug 24 10:54:49 default kernel: [36363.986125] [<ffffffff81829e15>] schedule+0x35/0x80
Aug 24 10:54:49 default kernel: [36363.986182] [<ffffffffc025a0fc>] amd_sched_entity_push_job+0x5c/0x100 [amdgpu]
Aug 24 10:54:49 default kernel: [36363.986191] [<ffffffff810c3ca0>] ? wake_atomic_t_function+0x60/0x60
Aug 24 10:54:49 default kernel: [36363.986244] [<ffffffffc025a6ea>] amdgpu_sched_ib_submit_kernel_helper+0xda/0x1b0 [amdgpu]
Aug 24 10:54:49 default kernel: [36363.986288] [<ffffffffc021ba9d>] amdgpu_vm_bo_update_mapping+0x32d/0x5a0 [amdgpu]
Aug 24 10:54:49 default kernel: [36363.986332] [<ffffffffc021c9f4>] amdgpu_vm_bo_update+0x104/0x290 [amdgpu]
Aug 24 10:54:49 default kernel: [36363.986369] [<ffffffffc020c7cc>] amdgpu_gem_va_update_vm+0x1ac/0x1d0 [amdgpu]
Aug 24 10:54:49 default kernel: [36363.986410] [<ffffffffc021cf01>] ? amdgpu_vm_bo_map+0x131/0x490 [amdgpu]
Aug 24 10:54:49 default kernel: [36363.986448] [<ffffffffc020dac6>] amdgpu_gem_va_ioctl+0x286/0x3f0 [amdgpu]
Aug 24 10:54:49 default kernel: [36363.986480] [<ffffffffc0098742>] drm_ioctl+0x152/0x540 [drm]
Aug 24 10:54:49 default kernel: [36363.986517] [<ffffffffc020d840>] ? amdgpu_gem_metadata_ioctl+0x240/0x240 [amdgpu]
Aug 24 10:54:49 default kernel: [36363.986525] [<ffffffff8120d5a6>] ? do_readv_writev+0x146/0x230
Aug 24 10:54:49 default kernel: [36363.986532] [<ffffffff813fa039>] ? timerqueue_add+0x59/0xb0
Aug 24 10:54:49 default kernel: [36363.986562] [<ffffffffc01f604c>] amdgpu_drm_ioctl+0x4c/0x80 [amdgpu]
Aug 24 10:54:49 default kernel: [36363.986567] [<ffffffff81220c3f>] do_vfs_ioctl+0x29f/0x490
Aug 24 10:54:49 default kernel: [36363.986575] [<ffffffff81707dd0>] ? __sys_recvmsg+0x80/0x90
Aug 24 10:54:49 default kernel: [36363.986580] [<ffffffff81220ea9>] SyS_ioctl+0x79/0x90
Aug 24 10:54:49 default kernel: [36363.986585] [<ffffffff8182def2>] entry_SYSCALL_64_fastpath+0x16/0x71
是 AMD 驱动程序吗？我该如何解决这个问题？