<html> <head> <base href="https://bugs.freedesktop.org/" /> </head> <body> <div> <a class="bz_bug_link bz_status_NEW " title="NEW --- - NV11 black screen & kernel hang on loading nouveaufb" href="https://bugs.freedesktop.org/show_bug.cgi?id=56461#c8">Comment # 8</a> on <a class="bz_bug_link bz_status_NEW " title="NEW --- - NV11 black screen & kernel hang on loading nouveaufb" href="https://bugs.freedesktop.org/show_bug.cgi?id=56461">bug 56461</a> from <a class="email" href="mailto:chris@edesix.com" title="Chris Paulson-Ellis <chris@edesix.com>"> Chris Paulson-Ellis</a> <pre>Okay, that was... interesting. I haven't quite managed to pin it down to a single commit, but here is what I've found out. I did a manual bisect, only looking at commits that make changes in drivers/gpu/drm/nouveau. The area of interest had unrelated problems causing a NULL pointer dereference and a compile problem. I fixed this by cherry picking the following 2 commits each time I tested a new commit: dea7e0ac ttm: fix agp since ttm tt rework 095f979a drm/nouveau/pm: fix build with HWMON off With these changes, the last nouveau commit that works is: d2edab4a drm/nouveau/pm: fix missing volt changes when boot voltage is undefined The next 3 nouveau commits all fail, but with a NULL pointer dereference in nouveau_hw_load_state() rather than with a black-screen hang: 2a44e499 drm/nouveau/disp: introduce proper init/fini, separate from create/destroy cf41d53b drm/nouveau: re-jig fbcon suspend/resume process a little 1772fcc6 drm/nv50/disp: fix evo for create/init + destroy/fini split In the next nouveau commit, the NULL pointer dereference has gone and it fails with the black-screen hang: f62b27db drm/nouveau: shutdown display on suspend/hibernate The stack trace for the 3 commits that oops rather than hang is as follows: [ 51.360006] Call Trace: [ 51.360006] [<f0c78c69>] ? nv_crtc_restore+0x52/0x10f [nouveau] [ 51.360006] [<f0cd3215>] ? ch7006_write+0x1f/0x50 [ch7006] [ 51.360006] [<f0c7a623>] ? nv04_display_init+0x48/0x58 [nouveau] [ 51.360006] [<f0c3214a>] ? nouveau_display_create+0x211/0x3f2 [nouveau] [ 51.360006] [<f0c12b16>] ? nouveau_card_init+0x138a/0x1459 [nouveau] [ 51.360006] [<f0c11744>] ? nouveau_stub_init+0x3/0x3 [nouveau] [ 51.360006] [<f0c13092>] ? nouveau_load+0x3ce/0x6ad [nouveau] [ 51.360006] [<f0ade3e0>] ? drm_get_pci_dev+0x13e/0x249 [drm] [ 51.360006] [<c104580d>] ? __blocking_notifier_call_chain+0x47/0x4f [ 51.360006] [<c113eb56>] ? pci_device_probe+0x47/0x68 [ 51.360006] [<c11ab567>] ? driver_probe_device+0x4a/0x13a [ 51.360006] [<c113ea91>] ? pci_match_device+0x8b/0x99 [ 51.360006] [<c11ab6b9>] ? __driver_attach+0x62/0x64 [ 51.360006] [<c11ab657>] ? driver_probe_device+0x13a/0x13a [ 51.360006] [<c11aaa38>] ? bus_for_each_dev+0x3f/0x63 [ 51.360006] [<c113eac2>] ? pci_dev_put+0xd/0xd [ 51.360006] [<c11ab329>] ? driver_attach+0x19/0x1e [ 51.360006] [<c11ab657>] ? driver_probe_device+0x13a/0x13a [ 51.360006] [<c11ab0a8>] ? bus_add_driver+0x17d/0x24d [ 51.360006] [<c113eac2>] ? pci_dev_put+0xd/0xd [ 51.360006] [<c11ab8a9>] ? driver_register+0x57/0xec [ 51.360006] [<f0ade51c>] ? drm_pci_init+0x31/0xe6 [drm] [ 51.360006] [<c113ef22>] ? __pci_register_driver+0x31/0x8f [ 51.360006] [<c1001027>] ? do_one_initcall+0x27/0x150 [ 51.360006] [<c108b650>] ? __vunmap+0xa0/0xd1 [ 51.360006] [<f0cb6000>] ? 0xf0cb5fff [ 51.360006] [<c1054f97>] ? sys_init_module+0xccc/0x18f2 [ 51.360006] [<c109be00>] ? sys_close+0x66/0xa7 [ 51.360006] [<c127fb10>] ? sysenter_do_call+0x12/0x26 [ 51.360006] Code: 00 28 60 00 f6 05 10 83 ca f0 10 0f 85 1e 12 00 00 8b 83 00 02 00 00 8b 50 18 01 ea 89 c8 e8 45 fd 50 d0 8b 83 78 01 00 00 31 c9 <8b> 2c b8 85 ed 0f 95 c1 83 ff 01 19 ed 81 e5 00 e0 ff ff 81 c5 [ 51.360006] EIP: [<f0c227fc>] nouveau_hw_load_state+0x9a5/0x26d9 [nouveau] SS:ESP 0068:ee665cc4</pre> </div> <hr> You are receiving this mail because: <ul> <li>You are the assignee for the bug.</li> </ul> </body> </html>