我有一个自定义内核模块，该模块是从此补丁编译而成的，该模块logitech G19在其他G系列设备中增加了对键盘的支持。我对Ubuntu特立独行的内核的master分支（2.6.35）进行了很好的编译。
我可以引导和加载模块，但是我遇到了一个非常奇怪的情况。一旦加载模块（无论是在启动时还是通过modprobe），我都会出现黑屏，并且控制台锁定。
奇怪的是它不会锁定我的系统，而只是当前的控制台会话。我可以通过SSH进入自己的机器，它为我提供了一个终端和一个会话。我可以键入，甚至可以运行命令，它会给我输出。然后，它将绘制我的下一个提示，并立即将其锁定。
我看到dmesg其中存在一个空指针，并且得到以下堆栈跟踪：
[ 956.215836] input: Logitech G19 Gaming Keyboard as /devices/pci0000:00/0000:00:1d.7/usb1/1-2/1-2.1/1-2.1.2/1-2.1.2:1.1/input/input5
[ 956.216023] hid-g19 0003:046D:C229.0004: input,hiddev97,hidraw3: USB HID v1.11 Keypad [Logitech G19 Gaming Keyboard] on usb-0000:00:1d.7-2.1.2/input1
[ 956.216065] input: Logitech G19 as /devices/pci0000:00/0000:00:1d.7/usb1/1-2/1-2.1/1-2.1.2/1-2.1.2:1.1/input/input6
[ 956.216128] Registered led device: g19_97:orange:m1
[ 956.216146] Registered led device: g19_97:orange:m2
[ 956.216178] Registered led device: g19_97:orange:m3
[ 956.216198] Registered led device: g19_97:red:mr
[ 956.216216] Registered led device: g19_97:red:bl
[ 956.216235] Registered led device: g19_97:green:bl
[ 956.216259] Registered led device: g19_97:blue:bl
[ 956.216872] Console: switching to colour frame buffer device 40x30
[ 956.216899] BUG: unable to handle kernel NULL pointer dereference at 000000000000001c
[ 956.216903] IP: [<ffffffffa040b21b>] sys_imageblit+0x21b/0x4ec [sysimgblt]
[ 956.216911] PGD 273554067 PUD 2726ca067 PMD 0
[ 956.216914] Oops: 0000 [#1] SMP
[ 956.216917] last sysfs file: /sys/devices/pci0000:00/0000:00:1d.7/usb1/1-2/1-2.1/1-2.1.2/1-2.1.2:1.1/usb/hiddev1/uevent
[ 956.216921] CPU 5
[ 956.216922] Modules linked in: hid_g19(+) led_class hid_gfb fb_sys_fops sysimgblt sysfillrect syscopyarea btrfs zlib_deflate crc32c libcrc32c ufs qnx4 hfsplus hfs minix ntfs vfat msdos fat jfs xfs exportfs reiserfs snd_hda_codec_atihdmi snd_hda_intel snd_hda_codec snd_hwdep snd_pcm snd_seq_midi snd_rawmidi snd_seq_midi_event snd_seq snd_timer snd_seq_device ioatdma snd i5000_edac soundcore snd_page_alloc psmouse edac_core i5k_amb shpchp serio_raw dca ppdev parport_pc lp parport usbhid hid floppy e1000e
[ 956.216953]
[ 956.216956] Pid: 3147, comm: modprobe Not tainted 2.6.35-26-generic #46 DSBF-DE/System Product Name
[ 956.216959] RIP: 0010:[<ffffffffa040b21b>] [<ffffffffa040b21b>] sys_imageblit+0x21b/0x4ec [sysimgblt]
[ 956.216963] RSP: 0018:ffff8802766db738 EFLAGS: 00010246
[ 956.216965] RAX: 0000000000000000 RBX: ffff880273e71000 RCX: ffff880272e93b40
[ 956.216968] RDX: 0000000000000007 RSI: 0000000000000010 RDI: ffff880272e93b40
[ 956.216970] RBP: ffff8802766db7d8 R08: 0000000000000000 R09: ffff880272e93b98
[ 956.216972] R10: 0000000000000000 R11: 0000000000000001 R12: 0000000000000000
[ 956.216974] R13: 0000000000000010 R14: 0000000000000008 R15: ffff8802766db8c8
[ 956.216977] FS: 00007fcae7725700(0000) GS:ffff880001f40000(0000) knlGS:0000000000000000
[ 956.216979] CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b
[ 956.216981] CR2: 000000000000001c CR3: 000000026ba26000 CR4: 00000000000006e0
[ 956.216983] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[ 956.216986] DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
[ 956.216988] Process modprobe (pid: 3147, threadinfo ffff8802766da000, task ffff8802696a16e0)
[ 956.216990] Stack:
[ 956.216991] ffff8802766db778 ffffffff810746ae ffff8802766db700 ffff88026b2cadc0
[ 956.216994] <0> ffff8802766db778 ffffffff812beef9 ffff8802f66db947 ffff8802766db94f
[ 956.216998] <0> ffff8802766db848 00000000812bf22e ffff880272e93b40 ffffffff812feb40
[ 956.217001] Call Trace:
[ 956.217011] [<ffffffff810746ae>] ? send_signal+0x3e/0x90
[ 956.217018] [<ffffffff812beef9>] ? put_dec+0x59/0x60
[ 956.217023] [<ffffffff812feb40>] ? fbcon_resize+0xd0/0x230
[ 956.217027] [<ffffffffa04175da>] gfb_fb_imageblit+0x1a/0x30 [hid_gfb]
[ 956.217031] [<ffffffff813051b9>] soft_cursor+0x1c9/0x270
[ 956.217034] [<ffffffff81304e8b>] bit_cursor+0x65b/0x6c0
[ 956.217037] [<ffffffff812c1796>] ? vsnprintf+0x316/0x5a0
[ 956.217043] [<ffffffff81061045>] ? try_acquire_console_sem+0x15/0x60
[ 956.217046] [<ffffffff81300ca8>] fbcon_cursor+0x1d8/0x340
[ 956.217049] [<ffffffff81304830>] ? bit_cursor+0x0/0x6c0
[ 956.217054] [<ffffffff81368139>] hide_cursor+0x29/0x90
[ 956.217057] [<ffffffff8136b078>] redraw_screen+0x148/0x240
[ 956.217060] [<ffffffff8136b42e>] bind_con_driver+0x2be/0x3b0
[ 956.217063] [<ffffffff8136b569>] take_over_console+0x49/0x70
[ 956.217066] [<ffffffff812ff7fb>] fbcon_takeover+0x5b/0xb0
[ 956.217069] [<ffffffff81303ca5>] fbcon_event_notify+0x5c5/0x650
[ 956.217076] [<ffffffff8158e7f6>] notifier_call_chain+0x56/0x80
[ 956.217080] [<ffffffff8108510a>] __blocking_notifier_call_chain+0x5a/0x80
[ 956.217084] [<ffffffff81085146>] blocking_notifier_call_chain+0x16/0x20
[ 956.217089] [<ffffffff812f366b>] fb_notifier_call_chain+0x1b/0x20
[ 956.217092] [<ffffffff812f4c8c>] register_framebuffer+0x1ec/0x2e0
[ 956.217098] [<ffffffff814084f8>] ? usb_init_urb+0x28/0x40
[ 956.217101] [<ffffffffa041790f>] gfb_probe+0x21f/0x4f0 [hid_gfb]
[ 956.217107] [<ffffffffa0425778>] g19_probe+0x558/0xedc [hid_g19]
[ 956.217115] [<ffffffff811c059c>] ? sysfs_do_create_link+0xec/0x210
[ 956.217128] [<ffffffffa00330c7>] hid_device_probe+0x77/0xf0 [hid]
[ 956.217131] [<ffffffff81388aa2>] ? driver_sysfs_add+0x62/0x90
[ 956.217134] [<ffffffff81388bc8>] really_probe+0x68/0x190
[ 956.217138] [<ffffffff81388d35>] driver_probe_device+0x45/0x70
[ 956.217140] [<ffffffff81388dfb>] __driver_attach+0x9b/0xa0
[ 956.217143] [<ffffffff81388d60>] ? __driver_attach+0x0/0xa0
[ 956.217146] [<ffffffff81388008>] bus_for_each_dev+0x68/0x90
[ 956.217149] [<ffffffff81388a3e>] driver_attach+0x1e/0x20
[ 956.217151] [<ffffffff813882fe>] bus_add_driver+0xde/0x280
[ 956.217154] [<ffffffff81389140>] driver_register+0x80/0x150
[ 956.217157] [<ffffffff8158e7f6>] ? notifier_call_chain+0x56/0x80
[ 956.217161] [<ffffffffa042a000>] ? g19_init+0x0/0x20 [hid_g19]
[ 956.217166] [<ffffffffa0032913>] __hid_register_driver+0x53/0x90 [hid]
[ 956.217169] [<ffffffff81085115>] ? __blocking_notifier_call_chain+0x65/0x80
[ 956.217173] [<ffffffffa042a01e>] g19_init+0x1e/0x20 [hid_g19]
[ 956.217178] [<ffffffff8100204c>] do_one_initcall+0x3c/0x1a0
[ 956.217184] [<ffffffff8109bd9b>] sys_init_module+0xbb/0x200
[ 956.217192] [<ffffffff8100a0f2>] system_call_fastpath+0x16/0x1b
[ 956.217195] Code: 83 e1 fc 48 89 4d c8 eb d3 8b 83 14 01 00 00 83 f8 04 74 09 83 f8 02 0f 85 7b 01 00 00 48 8b 4d b0 48 8b 83 00 04 00 00 8b 51 10 <44> 8b 04 90 8b 51 14 8b 3c 90 44 8b 4d ac 45 85 c9 75 16 41 b9
[ 956.217218] RIP [<ffffffffa040b21b>] sys_imageblit+0x21b/0x4ec [sysimgblt]
[ 956.217221] RSP <ffff8802766db738>
[ 956.217223] CR2: 000000000000001c
[ 956.217227] ---[ end trace 95d6c6d6913ccc79 ]---谁能为我指出正确的方向，以进行调试？
stacktrace使我相信它不是hid-g15驱动程序，而是hid-gfb驱动程序，它为键盘上的LCD创建了帧缓冲区。这是有道理的，因为它锁定了我的显示/控制台，但深入研究内核代码并没有真正意义。因此，很大一部分是汇编和宏函数。
涉及我的新代码的stacktrace上的最后一个函数是gfb_fb_imageblit。该功能的整体是
struct gfb_data *par = info->par;
sys_imageblit(info, image);
gfb_fb_update(par);我读的堆栈跟踪错误吗？我想念什么吗？关于如何调试的任何提示？
好吧，我知道其他人显然已经使该模块正常工作。而且我不确定作者是否还在。我想这是与内核一起使用调试器的好地方。我应该问一个新问题还是只是等到我在这里得到更多答案？
—
法尔玛里2011年
如果您只是关心模块的可用性（并不一定通过修复模块以使其与内核一起使用来帮助自己和社区），请尝试使用与“其他人”使用的内核版本和配置相同的内核。
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imz-伊万·扎哈拉里舍夫（Ivan Zakharyaschev）2011年
@imz：好吧，我只看到它实际被使用过的一处提及，我不知道他们使用的确切内核和配置，只知道它是用meerkat内核构建的。不过，我想学习，所以有空的时候我可能会开始调试它。
—
法尔玛里
如果您自己进行调试，则最终可以在此处发布问题的最佳答案之一！
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imz-伊万·扎哈拉里谢夫（Ivan Zakharyaschev）2011年
pl2303通过仔细阅读代码并找到NULL指针的源，解决了模块中的类似错误。（然后，这个小小的修复程序由维护者GregKH进行。）也许，您可以使用调试器来帮助您，询问如何对内核使用调试器。还要联系代码的维护者，他们可能会有想法。